JP2004099635A - Photocurable, thermosetting resin composition, its molded product and cured product thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocurable, thermosetting resin composition which has high sensitivity and simultaneously, excels in the flexing resistance, folding endurance, flexibility, plating resistance, heat resistance, and electrical properties required for solder resists to be used in flexible printed-wiring boards and TAB tapes. <P>SOLUTION: The photocurable, thermosetting resin composition comprises (A) a carboxy group-containing photocurable resin to be obtained by reacting a linear polyfunctional epoxy compound having a specific structure with an unsaturated monocarboxylic acid, and then reacting the resulting product with a polybasic acid anhydride, (B) a carboxy group-containing photocurable resin to be obtained by adding an alkylene oxide to a compound having three or more phenolic hydroxy groups in the molecule, partially esterifying the obtained alcoholic hydroxy groups with an unsaturated monocarboxylic acid, and furthermore adding a polybasic acid anhydride to unreacted alcoholic hydroxy groups, (C) a photopolyemrization initiator, (D) an epoxy resin having two or more epoxy groups in the molecule, and (E) a diluent. <P>COPYRIGHT: (C)2004,JPO

Description

（式中、Ｒ^１、Ｒ^２は、水素原子又はメチル基を示し、Ｒ^３は、水素原子又はグリシジル基を示し、ｎは、１〜２０の値を示す。）
に、（ｂ）不飽和モノカルボン酸を反応させた後、（ｃ）多塩基酸無水物を反応させて得られるカルボキシル基含有光硬化性樹脂、
（Ｂ）（ｄ）１分子中に３個以上のフェノール性水酸基を有する化合物に（ｅ）アルキレンオキシドを付加し、得られたアルコール性水酸基を部分的に（ｂ）不飽和モノカルボン酸でエステル化し、更に未反応のアルコール性水酸基に（ｃ）多塩基酸無水物を付加させて得られるカルボキシル基含有光硬化性樹脂、
（Ｃ）光重合開始剤、（Ｄ）１分子中に２個以上のエポキシ基を有するエポキシ樹脂、及び（Ｅ）希釈剤を含有することを特徴とする光硬化性・熱硬化性樹脂組成物が提供される。
さらに本発明によれば、上記組成物を用いて絶縁層を形成したことを特徴とするフレキシブルプリント配線板、又はＴＡＢテープからなる電子部品が提供される。
【０００９】
【発明の実施の形態】
本発明者らは、前記目的の実現に向け鋭意研究した結果、（Ａ）（ａ）下記一般式（１）で示される線状の多官能エポキシ化合物
【化３】

（式中、Ｒ^１、Ｒ^２は、水素原子又はメチル基を示し、Ｒ^３は、水素原子又はグリシジル基を示し、ｎは、１〜２０の値を示す。）
に、（ｂ）不飽和モノカルボン酸を反応させた後、（ｃ）多塩基酸無水物を反応させて得られるカルボキシル基含有光硬化性樹脂、
（Ｂ）（ｄ）１分子中に３個以上のフェノール性水酸基を有する化合物に（ｅ）アルキレンオキシドを付加し、得られたアルコール性水酸基を部分的に（ｂ）不飽和モノカルボン酸でエステル化し、更に未反応のアルコール性水酸基に（ｃ）多塩基酸無水物を付加させて得られるカルボキシル基含有光硬化性樹脂、
（Ｃ）光重合開始剤、（Ｄ）１分子中に２個以上のエポキシ基を有するエポキシ樹脂、及び（Ｅ）希釈剤を含有する組成物が、高感度で、かつフレキシブルプリント配線板やＴＡＢテープに用いられるソルダーレジストに要求される耐屈曲性、耐折性、柔軟性、耐めっき性、耐熱性、電気特性に優れ、かつドライフィルムへの加工性に優れた光硬化性・熱硬化性組成物であることを見出し、本発明を完成するに至った。
即ち、本発明の光硬化性・熱硬化性樹脂組成物は、前記カルボキシル基含有光硬化性樹脂（Ｂ）を乳化補助剤兼感光性プレポリマーとして使用することにより、前記カルボキシル基含有光硬化性樹脂（Ａ）だけでは不十分な現像性を、他の特性を維持しながら付与するものである。このように、現像性が向上することにより、前記カルボキシル基含有光硬化性樹脂（Ａ）の分子量を上げることが可能になり、高感度化、及び耐屈曲性、耐折性、柔軟性の向上が、可能となった。
【００１０】
以下、本発明の光硬化性・熱硬化性樹脂組成物の各構成成分について詳しく説明する。
まず、前記カルボキシル基含有光硬化性樹脂（Ａ）としては、（ａ）下記一般式（１）で示される線状の多官能エポキシ化合物
【化４】

（式中、Ｒ^１、Ｒ^２は、水素原子又はメチル基を示し、Ｒ^３は、水素原子又はグリシジル基を示し、ｎは、１〜２０の値を示す。）
に、（ｂ）不飽和モノカルボン酸を反応させた後、（ｃ）多塩基酸無水物を反応させた樹脂が用いられる。
具体的には、一般式（１）で表される多官能エポキシ化合物は、一般式（１）中のＲ^３が全て水素原子であり、ｎの値が１〜２０であるビスフェノールＦ型あるいはビスフェノールＡ型２官能エポキシ化合物をジメチルスルホキシドなどの極性溶媒等に溶解し、エピハロヒドリン（例えば、エピクロルヒドリンなど）とアルカリ金属水酸化物（例えば、水酸化ナトリウムなど）を反応させることにより、多官能化したビスフェノール骨格の樹脂である。
一般式（１）のｎの値が、１未満の場合、指触乾燥性、ドライフィルム化する時の造膜性や耐クラック性が低下するので好ましくない。一方、ｎが２０を超えた場合、現像性が低下し、解像性が得られなくなるので好ましくない。また、エピハロヒドリンの付加量は、平均５０％以上が好ましく、より好ましくは、８０％以上である。エピハロヒドリンの付加量が５０％未満の場合、感光化した時の耐現像性が得られ難く、また耐水性も低下するので好ましくない。
このようにして得られた多官能エポキシ化合物（ａ）と、上記不飽和モノカルボン酸（ｂ）との反応生成物に、上記多塩基酸無水物（ｃ）を反応させることにより、カルボキシル基含有光硬化性樹脂（Ａ）が得られる。
【００１１】
上記不飽和モノカルボン酸（ｂ）は、前記多官能エポキシ化合物（ａ）にラジカル重合性（光硬化性）を付与するためのものであり、例えば、アクリル酸、メタクリル酸、クロトン酸、桂皮酸、β−アクリロキシプロピオン酸などが挙げられる。また、１個のヒドロキシ基と１個以上の（メタ）アクリロイル基を有する化合物と二塩基酸無水物との反応物などを用いることも出来る。これらの中で特に好ましいものとして、アクリル酸、メタアクリル酸が挙げられる。これらは、単独で又は２種以上を組み合わせて用いることができる。
上記不飽和モノカルボン酸（ｂ）の付加量は、前記多官能エポキシ化合物のエポキシ基１当量当たり、０．８〜１．２当量である。不飽和モノカルボン酸（ｂ）の付加量が０．８当量未満の場合、未反応のエポキシ基が残り、次に付加する多塩基酸無水物から誘導されるカルボキシル基と反応するため、ゲル化を起こしたり、保存安定性を低下させるため好ましくない。一方、付加量が１．２当量を超える場合、未反応の不飽和モノカルボン酸による臭気の問題や塗膜特性が低下するので好ましくない。
【００１２】
また、上記多塩基酸無水物（ｃ）としては、無水マレイン酸、無水コハク酸、無水イタコン酸、無水シトラコン酸、無水フタル酸、無水テトラヒドロフタル酸、無水ヘキサヒドロフタル酸、メチルテトラヒドロ無水フタル酸、メチルヘキサヒドロ無水フタル酸、メチルエンドメチレンテトラヒドロ無水フタル酸、エンドメチレンテトラヒドロ無水フタル酸、ドデセニルコハク酸無水物、無水クロレンド酸、無水トリメリット酸、無水ピロメリット酸、５−（２，５−ジオキソテトラヒドロフリル）−３−メチル−３−シクロヘキセン−１，２−ジカルボン酸無水物、ベンゾフェノンテトラカルボン酸無水物等が挙げられ、これらを単独で又は２種以上を組み合わせて用いることができる。これらの中でも、無水テトラヒドロフタル酸、無水ヘキサヒドロフタル酸、メチルテトラヒドロ無水フタル酸、メチルヘキサヒドロ無水フタル酸、メチルエンドメチレンテトラヒドロ無水フタル酸、エンドメチレンテトラヒドロ無水フタル酸などの脂環式二塩基酸無水物が、現像性、硬化性の面から特に好ましい。
上記多塩基酸無水物（ｃ）の付加量は、前記カルボキシル基含有光硬化性樹脂（Ａ）の酸価が６０〜１２０ｍｇＫＯＨ／ｇとなる範囲が好ましい。前記カルボキシル基含有光硬化性樹脂の酸価が６０ｍｇＫＯＨ／ｇ未満の場合、現像性が得られなくなるので好ましくない。一方、この酸価が１２０ｍｇＫＯＨ／ｇを超える場合、耐めっき性等の塗膜特性が低下するので好ましくない。
【００１３】
前記カルボキシル基含有光硬化性樹脂（Ｂ）は、１分子中に３個以上のフェノール性水酸基を有する化合物（ｄ）にアルキレンオキシド（ｅ）を付加し、得られたアルコール性水酸基を部分的に不飽和モノカルボン酸（ｂ）でエステル化し、さらに未反応のアルコール性水酸基に多塩基酸無水物（ｃ）を付加させて得られる。
即ち、１分子中に３個以上のフェノール性水酸基を有する化合物（ｄ）に、アルキレンオキシド（ｅ）を付加することにより、主骨格から離れた自由度の高い位置にアルコール性水酸基を有するポリエーテルポリオールを、合成することができる。このポリエーテルポリオールのアルコール性水酸基に、部分的に前記不飽和モノカルボン酸（ｂ）でエステル化することにより、光硬化性を付与することができる。さらに、残存するアルコール性水酸基に前記多塩基酸無水物（ｄ）を反応させることにより、カルボキシル基を導入することができ、アルカリ可溶性にすることが可能となる。
【００１４】
上記１分子中に３個以上のフェノール性水酸基を有する化合物（ｄ）としては、例えば、トリス（ヒドロキシフェニル）メタン、テトラ（ヒドロキシフェニル）エタン、フェノールノボラック樹脂、クレゾールノボラック樹脂、アルキル変性フェノールノボラック樹脂、ビスフェノールＡノボラック型樹脂、ジシクロペンタジエン型フェノール樹脂、ザイロック樹脂、コプナ樹脂、テルペンフェノール変性フェノール樹脂、ポリビニルフェノール類など公知慣用のものを、単独又は２種類以上を組み合わせて使用することができる。
上記化合物（ｄ）中のフェノール性水酸基が３個未満の化合物の場合、得られるカルボキシル基含有光硬化性樹脂の感光基数が少なく、光硬化しても三次元化し難くなり、耐現像性が得られ無くなるので好ましくない。
【００１５】
上記アルキレンオキシド（ｅ）としては、エチレンオキシド、プロピレンオキシド、ブチレンオキシド、イチブチレンオキシド、トリメチレンオキシド、テトラヒドロフラン、テトラヒドロピランなどが挙げられる。これらの中で、柔軟性、反応の容易さ等から、エチレンオキシド、プロピレンオキシドが好ましく、より好ましくは耐水性の良いプロピレンオキシドが用いられる。
アルキレンオキシド（ｅ）の付加量は、上記１分子中に３個以上のフェノール性水酸基を持つ化合物（ｄ）のフェノール性水酸基１モルに対して、１．０〜１０．０モルである。アルキレンオキシド（ｅ）の付加量がフェノール性水酸基１モルに対して１．０モル未満の場合、不飽和モノカルボン酸（ｂ）によるエステル化や多塩基酸無水物（ｃ）の付加反応の起こり難いフェノール性水酸基が残り、また柔軟性等が得られ難くなるので好ましくなく、一方、付加量が１０．０モルを超える場合、耐水性、指触乾燥性等が得られ難くなるで、好ましくない。
【００１６】
また、カルボキシル基含有光硬化性樹脂（Ｂ）の合成に用いられる不飽和モノカルボン酸（ｂ）と多塩基酸無水物（ｃ）は、カルボキシル基含有光硬化性樹脂（Ａ）に用いたものと同様のものが用いられる。
上記多塩基酸無水物（ｃ）の付加量は、上記カルボキシル基含有光硬化性樹脂（Ｂ）の酸価が２０〜１２０ｍｇＫＯＨ／ｇとなる範囲が好ましい。上記カルボキシル基含有光硬化性樹脂（Ｂ）の酸価が２０ｍｇＫＯＨ／ｇ未満の場合、アルカリ水溶液による現像性が得られなくなるので好ましくない。一方、この酸価が１２０ｍｇＫＯＨ／ｇを超える場合、光硬化基の付加量が低減し、感度が低下するので好ましくない。
具体的には、前記１分子中に３個以上のフェノール性水酸基を有する化合物（ｄ）から誘導されるポリオール化合物のアルコール性水酸基に、不飽和モノカルボン酸（ｂ）と多塩基酸無水物（ｃ）を、８：２〜４：６の範囲で反応させることが好ましい。
【００１７】
前記光重合開始剤（Ｃ）としては、例えば、ベンゾイン、ベンゾインメチルエーテル、ベンゾインエチルエーテル、ベンゾインイソプロピルエーテル等のベンゾインとベンゾインアルキルエーテル類；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、２，２−ジエトキシ−２−フェニルアセトフェノン、１，１−ジクロロアセトフェノン等のアセトフェノン類；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−ジメチルアミノ−１−（４−モルホリノフェニル）−ブタン−１−オン、Ｎ，Ｎ−ジメチルアミノアセトフェノン等のアミノアセトフェノン類；２−メチルアントラキノン、２−エチルアントラキノン、２−ｔ−ブチルアントラキノン、１−クロロアントラキノン等のアントラキノン類；２，４−ジメチルチオキサントン、２，４−ジエチルチオキサントン、２−クロロチオキサントン、２，４−ジイソプロピルチオキサントン等のチオキサントン類；アセトフェノンジメチルケタール、ベンジルジメチルケタール等のケタール類；ベンゾフェノン、４，４´−ビスジエチルアミノベンゾフェノン等のベンゾフェノン類又はキサントン類；２，４，６−トリメチルベンゾイルジフェニルホスフィンオキサイドなどが挙げられる。これら公知慣用の光重合開始剤は、単独で又は２種類以上の混合物として使用でき、さらにはＮ，Ｎ−ジメチルアミノ安息香酸エチルエステル、Ｎ，Ｎ−ジメチルアミノ安息香酸イソアミルエステル、ペンチル−４−ジメチルアミノベンゾエート、トリエチルアミン、トリエタノールアミン等の三級アミン類などの光開始助剤を加えることができる。また可視光領域に吸収のあるＣＧＩ−７８４（チバ・スペシャルティ・ケミカルズ社製）等のチタノセン化合物等も、光反応を促進するために添加することもできる。特に好ましい光重合開始剤は、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−ジメチルアミノ−１−（４−モルホリノフェニル）−ブタン−１−オン、２，４，６−トリメチルベンゾイルジフェニルホスフィンオキサイド等であるが、特にこれらに限られるものではなく、紫外光もしくは可視光領域で光を吸収し、（メタ）アクリロイル基等の不飽和基をラジカル重合させるものであれば、光重合開始剤、光開始助剤に限らず、単独で又は２種類以上を併用して使用できる。
【００１８】
前記光重合開始剤（Ｃ）の配合量は、前記カルボキシル基含有光硬化性樹脂（Ａ），（Ｂ）の合計量１００質量部（固形分として、以下同様）に対して、０．１〜２５質量部、好ましくは０．５〜２０質量部の割合が望ましい。光重合開始剤（Ｃ）の配合量が上記範囲よりも少ない場合、活性エネルギー線の照射を行なっても硬化しないか、もしくは照射時間を増やす必要があり、適切な塗膜物性が得られ難くなる。一方、上記範囲よりも多量に光重合開始剤を添加しても、光硬化性に変化は無く、経済的に好ましくない。
【００１９】
前記１分子中に２個以上のエポキシ基を有するエポキシ樹脂（Ｄ）としては、公知慣用の各種エポキシ樹脂、例えばビスフェノールＡ型エポキシ樹脂、ビスフェノールＦ型エポキシ樹脂、ビスフェノールＳ型エポキシ樹脂、臭素化ビスフェノールＡ型エポキシ樹脂、水添ビスフェノールＡ型エポキシ樹脂、ビフェノール型エポキシ樹脂、ビキシレノール型エポキシ樹脂、フェノールノボラック型エポキシ樹脂、クレゾールノボラック型エポキシ樹脂、トリス（ヒドロキシフェニル）メタン型エポキシ樹脂、ジシクロペンタジエン骨格含有エポキシ樹脂、臭素化フェノールノボラック型エポキシ樹脂、ビスフェノールＡのノボラック型エポキシ樹脂などのグリシジルエーテル化合物；テレフタル酸ジグリシジルエステル、ヘキサヒドロフタル酸ジグリシジルエステル、ダイマー酸ジグリシジルエステルなどのグリシジルエステル化合物；トリグリシジルイソシアヌレートなどの複素環式エポキシ樹脂；Ｎ，Ｎ，Ｎ’，Ｎ’−テトラグリシジルメタキシレンジアミン、Ｎ，Ｎ，Ｎ’，Ｎ’−テトラグリシジルビスアミノメチルシクロヘキサン、Ｎ，Ｎ−ジグリシジルアニリンなどのグリシジルアミン化合物；ゴム変性エポキシ樹脂；脂環式エポキシ樹脂などが挙げられる。これらのエポキシ樹脂は、単独で又は二種類以上を組み合わせて用いることができる。
【００２０】
上記エポキシ樹脂（Ｄ）は、熱硬化することにより、ソルダーレジストに必要な密着性、耐熱性等の特性を向上させる。その配合量は、前記カルボキシル基含有光硬化性樹脂（Ａ），（Ｂ）のカルボキシル基１当量当たり、０．８〜２．０当量であり、好ましくは１．０〜１．６当量である。エポキシ樹脂（Ｄ）の配合量が０．８当量未満の場合、硬化塗膜の吸湿性、はんだ耐熱性、電気特性等が低下するので好ましくない。一方、エポキシ樹脂（Ｄ）の配合量が２．０当量を超えると、塗膜の現像性や硬化塗膜の耐めっき性が悪くなり、また耐クラック性も低下するので好ましくない。
【００２１】
本発明の光硬化性・熱硬化性樹脂組成物は、指触乾燥性を得るために、固形又は半固形のカルボキシル基含有光硬化性樹脂（Ａ），（Ｂ）を用いているため、樹脂を溶解させ、また組成物を塗布方法に適した粘度に調整するため、光重合性モノマーや有機溶剤等を希釈剤（Ｅ）として用いる必要がある。また、光重合性モノマーは、光硬化性を上げることもできる。
上記希釈剤（Ｅ）として用いられる光重合性モノマーとしては、２−ヒドロキシエチルアクリレート、２−ヒドロキシプロピルアクリレートなどのヒドロキシアルキルアクリレート類；エチレングリコール、ジ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などのグリコールのモノ又はジアクリレート類；Ｎ，Ｎ−ジメチルアクリルアミド、Ｎ−メチロールアクリルアミド、Ｎ，Ｎ−ジメチルアミノプロピルアクリルアミドなどのアクリルアミド類；Ｎ，Ｎ−ジメチルアミノエチルアクリレート、Ｎ，Ｎ−ジメチルアミノプロピルアクリレートなどのアミノアルキルアクリレート類；ヘキサンジオール、トリメチロールプロパン、ペンタエリスリトール、ジペンタエリスリトール、トリシクロデカンジメタノール、トリス−ヒドロキシエチルイソシアヌレートなどの多価アルコール又はこれらのエチレオキサイド付加物もしくはプロピレンオキサイド付加物などの多価アクリレート類；フェノキシアクリレート、ビスフェノールＡジアクリレート、及びこれらのフェノール類のエチレンオキサイド付加物もしくはプロピレンオキサイド付加物などのアクリレート類；グリセリンジグリシジルエーテル、グリセリントリグリシジルエーテル、トリメチロールプロパントリグリシジルエーテル、トリグリシジルイソシアヌレートなどのグリシジルエーテルのアクリレート類；各種ウレタンアクリレート類；及びメラミンアクリレート、及び／又は上記アクリレートに対応する各メタクリレート類などが挙げられる。これらの光重合性モノマーは、単独で又は２種類以上を組み合わせて用いることができる。
【００２２】
上記希釈剤（Ｅ）として用いられる有機溶剤としては、メチルエチルケトン、シクロヘキサノン等のケトン類；トルエン、キシレン、テトラメチルベンゼン等の芳香族炭化水素類；セロソルブ、メチルセロソルブ、ブチルセロソルブ、カルビトール、メチルカルビトール、ブチルカルビトール、プロピレングリコールモノメチルエーテル、ジプロピレングリコールモノメチルエーテル、ジプロピレングリコールジエチルエーテル、トリエチレングリコールモノエチルエーテル等のグリコールエーテル類；酢酸エーテル、酢酸ブチル及び上記グリコールエーテル類の酢酸エステル化物などのエステル類；エタノール、プロパノール、エチレングリコール、プロピレングリコール等のアルコール類；オクタン、デカン等の脂肪族炭化水素；石油エーテル、石油ナフサ、水添石油ナフサ、ソルベントナフサ等の石油系溶剤などが挙げられ、前記光硬化性樹脂（Ａ）及び（Ｂ）と相溶性が良いものが好ましい。また、ドライフィルム化に際しては、沸点が１５０℃以下の有機溶剤が作業性の面から好ましい。
【００２３】
本発明の光硬化性・熱硬化性樹脂組成物は、塗膜の硬化収縮を抑制し、印刷性、密着性、硬度などの特性を向上させるため、必要に応じて、硫酸バリウム、チタン酸バリウム、酸化ケイ素紛、微粉状酸化ケイ素、無定形シリカ、結晶性シリカ、溶融シリカ、球状シリカ、タルク、クレー、炭酸マグネシウム、炭酸カルシウム、酸化アルミニウム、水酸化アルミニウム、マイカ等の公知慣用の無機フィラー及び／又はウレタンビーズなどの有機フィラーを、単独で又は２種以上を組み合わせて配合することができる。これら無機フィラー及び／又は有機フィラーの配合量は、前記カルボキシル基含有光硬化性樹脂（Ａ），（Ｂ）の合計量１００質量部当り、０〜２００質量部、好ましくは１０〜１００質量部が適当である。
【００２４】
また、本発明の光硬化性・熱硬化性樹脂組成物は、更に必要に応じて、カーボンブラック、酸化チタン、フタロシアニン・ブルー、フタロシアニン・グリーン、アイオジン・グリーン、ジスアゾイエロー、クリスタルバイオレット、ナフタレンブラックなどの公知慣用の着色剤；ハイドロキノン、ハイドロキノンモノメチルエーテル、ｔ−ブチルカテコール、ピロガロール、フェノチアジンなどの公知慣用の熱重合禁止剤；シリコーン系、フッ素系、高分子系などの消泡剤及び／又はレベリング剤；イミダゾール系、チアゾール系、トリアゾール系、シランカップリング剤等の密着性付与剤；ジシアンジアミド、メラミンなどの硬化触媒等、公知慣用の添加剤類を配合することができる。
【００２５】
以上のような組成を有する本発明の光硬化性・熱硬化性樹脂組成物は、必要に応じて前記有機溶剤等で希釈して塗布方法に適した粘度に調整し、これを例えば、回路形成されたフレキシブルプリント配線板、又はＴＡＢテープにスクリーン印刷法、カーテンコート法、スプレーコート法、ロールコート法等の方法により塗布し、例えば約６０〜１００℃の温度で組成物中に含まれる有機溶剤を揮発乾燥させることにより、塗膜を形成できる。
【００２６】
あるいは、前記組成物をドライフィルム化し回路形成されたフレキシブルプリント配線板、又はＴＡＢテープにラミネートし、光硬化性・熱硬化性樹脂組成物の塗膜を形成できる。
ドライフィルム化に際しては、本発明の光硬化性・熱硬化性樹脂組成物を前記有機溶剤で希釈して適切な粘度とし、支持体フィルム上にフィルムコーター等で塗布・乾燥して、ドライフィルムを作製することができる。塗布膜厚としては、乾燥後で、通常１０〜５０μｍ、好ましくは１５〜４０μｍである。
支持体フィルムに上記組成物を塗布する方法としては、例えば、ナイフコーター塗布、コンマコーター塗布、ダイコーター塗布、グラビアコーター塗布、ロールコータ塗布、スプレーコーター塗布等で行なうことができる。また、支持体フィルムとしては、例えば、ポリエチレンテレフタレートフィルム等のポリエステルフィルム、ポリアミドイミドフィルム、ポリプロピレンフィルム、ポリスチレンフィルム等のフィルムを用いることができる。
【００２７】
支持体フィルム上に上記組成物を塗布した後、通常、５０〜１３０℃の温度で１〜３０分間乾燥して膜を得ることができる。さらに、膜の表面に塵が付着するのを防ぐなどの目的で、膜の表面に剥離可能なカバーフィルムを積層することが望ましい。
剥離可能なカバーフィルムとしては、例えば、ポリエチレンフィルム、ポリテトラフルオロエチレンフィルム、ポリプロピレンフィルム、表面処理した紙等を用いることができ、カバーフィルムを剥離するときに膜と支持体との接着力よりも膜とカバーフィルムとの接着力がより小さいものであればよい。
【００２８】
その後、上記いずれかの方法で作製した塗膜を、所定のパターンを形成したフォトマスクを通して選択的に活性エネルギー線により露光し、未露光部を希アルカリ水溶液により現像してレジストパターンを形成でき、さらに、活性エネルギー線の照射後加熱硬化もしくは加熱硬化後活性エネルギー線の照射、又は、加熱硬化のみで最終硬化（本硬化）させることにより、耐屈曲性、耐折性、耐柔軟性、反り、耐めっき性、耐熱性、電気特性に優れた硬化皮膜（例えば、ソルダーレジスト皮膜）を形成することができる。
【００２９】
上記希アルカリ水溶液としては、水酸化カリウム、水酸化ナトリウム、炭酸ナトリウム、炭酸カリウム、リン酸ナトリウム、ケイ酸ナトリウム、アンモニア、アミン類などの希アルカリ水溶液が使用できる。
また、光硬化させるための照射光源としては、低圧水銀灯、中圧水銀灯、高圧水銀灯、超高圧水銀灯、キセノンランプ又はメタルハライドランプなどが適当である。その他、レーザー光線なども活性エネルギー線として利用できる。
【００３０】
【実施例】
以下に実施例及び比較例を示して本発明について具体的に説明するが、本発明が下記実施例に限定されるものでないことはもとよりである。なお、以下において「部」及び「％」とあるのは、特に断りのない限り全て質量基準である。
【００３１】
〔カルボキシル基含有光硬化性樹脂（Ａ）の合成〕
ビスフェノールＦ型エポキシ樹脂（エポキシ当量＝９５０、軟化点８５℃、平均重合度ｎ＝６．２）３８０部とエピクロルヒドリン９２５部をジメチルスルホキシド４６２．５部に溶解させた後、攪拌下７０℃で純度９８．５％ＮａＯＨ６０．９部（１．５モル）を１００分かけて添加した。添加後さらに７０℃で３時間反応を行った。反応終了後、水２５０部を加え水洗を行った。油水分離後、油層よりジメチルスルホキシドの大半及び過剰の未反応エピクロルヒドリンを減圧下に蒸留回収し、残留した複製塩とジメチルスルホキシドを含む反応生成物をメチルイソブチルケトン７５０部に溶解させ、さらに３０％ＮａＯＨ水溶液１０部を加え、７０℃で１時間反応させた。反応終了後、水２００部で２回水洗を行った。油水分離後、油層よりチルイソブチルケトンを蒸留回収して、エポキシ当量＝３１０、軟化点６９℃の多官能エポキシ化合物（ａ）を得た。得られた多官能エポキシ化合物（ａ）は、エポキシ当量から計算すると、前記出発物質ビスフェノールＦ型エポキシ樹脂におけるアルコール性水酸基６．２個のうち約５個がエポキシ化されたものであった。
この多官能エポキシ化合物（ａ）３１０部及びジエチレングリコールモノエチルエーテルアセテート２８２部を攪拌機及び還流冷却器の付いた四つ口フラスコに仕込み、９０℃で加熱・攪拌し、溶解した。得られた溶液を一旦６０℃まで冷却し、アクリル酸７２部、メチルハイドロキノン０．５部、トリフェニルホスフィン２部を加え、１００℃に加熱し、約６０時間反応させ、酸価が０．２ｍｇＫＯＨ／ｇの反応物を得た。これに無水テトラヒドロフタル酸１４０部を加え、９０℃に加熱し、固形分酸価が１００ｍｇＫＯＨ／ｇになるまで反応を行い、光硬化性樹脂（Ｂ）を６５％含有する溶液を得た。以下、この溶液をＡ−１ワニスと称す。
【００３２】
〔カルボキシル基含有光硬化性樹脂（Ｂ）の合成〕
温度計、窒素導入装置兼アルキレンオキシド導入装置及び撹拌装置を備えたオートクレーブに、昭和高分子（株）製クレゾールノボラック樹脂（商品名「ショウノール　ＣＲＧ−９５１」、ＯＨ当量：１１８）５９部、５０％水酸化ナトリウム水溶液２．６部、トルエン／メチルイソブチルケトン（質量比＝２／１）５０部を仕込み、撹拌しながら系内を窒素置換し、次に加熱昇温し、１５０℃、９ｋｇ／ｃｍ^２でプロピレンオキシド９０部を徐々に導入し反応させた。反応はゲージ圧０．０ｋｇ／ｃｍ^２となるまで約６時間続けた後、室温まで冷却した。さらに、５０％水酸化カリウム水溶液３．０部を添加し、系内を窒素置換して、加熱昇温し、１５０℃、９ｋｇ／ｃｍ^２でプロピレンオキシド９０部を徐々に導入し、ゲージ圧０．０ｋｇ／ｃｍ^２となるまで反応を続けた後、室温まで冷却した。この反応溶液を３５％塩酸水溶液で、触媒として添加した水酸化ナトリウムと水酸化カリウムを中和した。その後、この反応生成物をトルエンで希釈し、３回水洗し、エバポレーターにて脱溶剤して、水酸基当量が４６７ｇ／ｅｑ．であるクレゾールノボラック樹脂のアルキレンオキシド付加物を得た。これは、フェノール性水酸基１モルに対して、アルキレンオキシドが平均６．０モル付加したものであった。
得られたクレゾールノボラック樹脂のアルキレンオキシド付加物２３３．５部、アクリル酸２５．２部、ｐ−トルエンスルホン酸３．０部、ハイドロキノンモノメチルエーテル０．０５部、トルエン１００部を撹拌機、温度計、空気吹き込み管を備えた反応器に仕込み、空気を吹き込みながら攪拌して、１１０℃で６時間反応させた。反応により生成した水がトルエンとの共沸混合物として留出し始めた後、さらに５時間反応させ、室温まで冷却した。得られた反応溶液を５％ＮａＣｌ水溶液で水洗し、エバポレーターにてトルエンを留去し、ジエチレングリコールモノエチルエーテルアセテートを加えて、不揮発分６０％のクレゾールノボラック骨格のアクリレート樹脂溶液を得た。
次に、撹拌器及び還流冷却器の付いた４つ口フラスコに、得られたクレゾールノボラック骨格のアクリレート樹脂溶液２１５．５部、ハイドロキノンモノメチルエーテル０．０５部、トリフェニルホスフィン０．２部を仕込み、この混合物を１２０℃に加熱し、無水テトラヒドロフタル酸１１．４部を加え、６時間反応させ、冷却後、取り出した。このようにして得られたカルボキシル基含有光硬化性樹脂は、不揮発分６２％、固形分酸価３０ｍｇＫＯＨ／ｇであった。以下、この反応溶液をＢ−１ワニスと称す。
【００３３】
〔ウレタンアクリレート樹脂の合成〕
温度計、撹拌器、滴下ロート、及び還流冷却器を備えたフラスコに、ビスフェノールＡ型エポキシ樹脂（エピクロン　４０５０、大日本インキ化学工業社製、エポキシ当量＝９５０）４７５部とジエチレングリコールモノエチルエーテルアセテート４６５部を量り取り、加熱溶解した。次に、重合禁止剤としてハイドロキノン０．１部と、反応触媒としてトリフェニルホスフィン１．０部を加えた。この混合物を９５〜１０５℃に加熱し、アクリル酸３６部を徐々に滴下し、酸価が１．０ｍｇＫＯＨ／ｇ以下になるまで、約１６時間反応させた。この反応生成物を、常温まで冷却し、ジラウリン酸ジブチル錫０．２部を加え、約７０℃に加熱し、２−メタクリロイルオキシエチルイソシアネート１８６部を徐々に加え、赤外吸光分析により、イソシアネートの吸収ピークが無くなるまで、約６時間反応させ、エポキシウレタンアクリレートの不揮発分６０％の溶液を得た。以下、この溶液をウレタンアクリートワニスと称す。
【００３４】
〔比較合成例〕
温度計、撹拌器、滴下ロート、及び還流冷却器を備えたフラスコに、クレゾールノボラック型エポキシ樹脂（エピクロンＮ−６８０、大日本インキ化学工業社製、エポキシ当量＝２１０）２１０部とジエチレングリコールモノエチルエーテルアセテート９６．４部を量り取り、加熱溶解した。次に、重合禁止剤としてハイドロキノン０．１部と、反応触媒としてトリフェニルホスフィン２．０部を加えた。この混合物を９５〜１０５℃に加熱し、アクリル酸７２部を徐々に滴下し、酸価が３．０ｍｇＫＯＨ／ｇ以下になるまで、約１６時間反応させた。この反応生成物を、８０〜９０℃まで冷却し、無水テトラヒドロフタル酸７６．１部を加え、赤外吸光分析により、酸無水物の吸収ピーク（１７８０ｃｍ^−１）が無くなるまで、約６時間反応させた。この反応液に、出光石油化学社製の芳香族系溶剤イプゾール＃１５０　９６．４部を加え、希釈した後、取り出した。このようにして得られた２個以上のアクリロイル基とカルボキシル基を併せ持つ樹脂化合物は、不揮発分６５％、固形物の酸価７８ｍｇＫＯＨ／ｇであった。以下、この反応溶液をＲ−１ワニスと称す。
【００３５】
（実施例１〜３及び比較例１〜３）
上記合成例で得たＡ−１，Ｂ−１，Ｒ−１ワニス及びウレタンアクリレートワニスを用いて、表１に示す配合割合で各成分を配合し、３本ロールミルを用いて混練して、各光硬化性・熱硬化性樹脂組成物を調製した。
【００３６】
【表１】

【００３７】
（１）ドライフィルム形成性
上記のようにして得られた各組成物を、厚さ３８μｍのＰＥＴフィルムにナイフコーターを用いて、乾燥膜厚が３５μｍになるように塗布した後、１１０℃で５分間乾燥して、各組成物のドライフィルムを得た。
各組成物のドライフィルムを、ロールに巻き取った後、乾燥塗膜表面の状態を、ルーペを用いてクラック等の発生状況を調べ、以下のように評価した。
○：クラック等の発生が全く無い。
△：微細なクラックが少し発生。
×：クラックが発生し、剥がれが起こる。
【００３８】
（２）現像性
上記各実施例及び比較例の光硬化性・熱硬化性樹脂組成物を、パターン形成された銅箔基板上にスクリーン印刷で全面塗布し、８０℃で３０分乾燥し、室温まで放冷した後、３０℃の１％Ｎａ_２ＣＯ_３水溶液をスプレー圧２ｋｇ／ｃｍ^２の条件で３０秒間現像を行い、乾燥塗膜の現像残りの有無を目視で確認した。判定基準は以下のとおりである。
○：完全に現像されている。
△：一部塗膜が残っている。
×：塗膜が完全に残っている。
【００３９】
（３）感度
上記のようにして得られた各組成物を、ポリイミドフレキシブルプリント配線板にスクリーン印刷法で乾燥膜厚が約２０μｍになるように全面印刷し、熱風循環式乾燥炉で８０℃，２０分乾燥し、評価基板を作製した。この評価基板に、コダックＮｏ．２のステップタブレットを当て、３００ｍＪ／ｃｍ^２で露光し、スプレー圧２ｋｇ／ｃｍ^２の１ｗｔ％Ｎａ_２ＣＯ_３水溶液で１分間現像し、塗膜が完全に除去されている段数を評価した。
【００４０】
上記のようにして得られた各組成物を、回路形成されたポリイミドフレキシブルプリント配線板に、スクリーン印刷法で乾燥膜厚が約２０μｍになるように全面印刷し、熱風循環式乾燥炉で８０℃，２０分乾燥した。これを室温まで冷却した後、各組成物で感度が６段となるような適正露光量でパターン露光し、スプレー圧２ｋｇ／ｃｍ^２の１ｗｔ％Ｎａ_２ＣＯ_３水溶液で１分間現像した。この基板を、熱風循環式乾燥炉を用いて、１５０℃で６０分間熱硬化を行い、評価基板を作製した。
以下、この評価基板を用いて、反り、耐屈曲性、はんだ耐熱性、無電解金めっき耐性を評価した。
【００４１】
（４）反り
上記評価基板を、５ｃｍ四方に裁断し、水平な場所にサンプルを置き、ノギスを用いて、反り量を測定した。
○：反り量が１ｍｍ未満。
△：反り量が１ｍｍ以上３ｍｍ未満。
×：反り量が３ｍｍ以上。
【００４２】
（５）耐屈曲性
前記評価基板を、幅１ｃｍ、長さ１０ｃｍに裁断し、塗膜面を外側に１８０℃折り曲げを行い、クラックの有無を観察した。
○：全く、異常の無いもの。
△：僅かに、微細なクラックが見られるもの。
×：基材部まで到達するクラックが見られるもの。
【００４３】
（６）はんだ耐熱性
前記評価基板に、ロジン系フラックスを塗布し、２６０℃に設定したはんだ槽に、３０秒間浸漬した。この評価基板を有機溶剤で洗浄したのち、セロハンテープによるピーリング試験を行い、以下のように判定した。
○：膨れ、剥がれ、変色等の異常なし。
△：変色のみ発生。
×：膨れ、又は剥がれを発生。
【００４４】
（７）無電解金めっき耐性
前記評価基板を、市販の無電解ニッケルめっき液と無電解金めっき液を用いて、無電解めっきを行った。
このめっき後の評価基板について、セロハン粘着テープによるピールテストを行い、レジスト層の剥がれについて評価した。
○：全く変化が認められないもの。
△：ほんの僅か剥がれの変化があるもの。
×：塗膜全体に剥がれがあるのもの。
【００４５】
これらの結果を、表２にまとめて示す。
【表２】

【００４６】
【発明の効果】
以上説明したように本発明の光硬化性・熱硬化性樹脂組成物によれば、高感度で、フレキシブルプリント配線板やＴＡＢテープに必要な耐屈曲性、耐折性、柔軟性、反り、耐めっき性、耐熱性、電気特性等に優れた塗膜を形成することができる。
また、ドライフィルム形成性に優れていることから、ロール・ツー・ロール法に適した光硬化性・熱硬化性樹脂組成物のドライフィルムを提供することができる。
しかも、本発明の光硬化性・熱硬化性樹脂組成物又はその成形物を、フレキシブルプリント配線板又はＴＡＢテープ上に、塗布・乾燥又はラミネートした後、活性エネルギー線照射及び加熱硬化することにより、耐屈曲性、耐折性、柔軟性、耐めっき性、耐熱性、電気特性に優れた硬化物が得られ、信頼性の高いフレキシブルプリント配線板、又はＴＡＢテープを提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photo-curable / thermo-curable resin useful for a flexible printed wiring board or a TAB (Tape Automated Bonding) tape. More specifically, it is suitable for forming a coating film with excellent bending resistance, folding resistance, flexibility, warpage, plating resistance, heat resistance, and electrical characteristics required for flexible printed wiring boards and TAB tapes, and has high sensitivity. The present invention relates to a photocurable / thermosetting resin composition, a molded product thereof, and a cured product thereof.
[0002]
[Prior art]
With the recent rapid progress of semiconductor components, electronic devices tend to be smaller and lighter, have higher performance, and have more functions. Following these trends, the density of printed wiring boards has been increasing. Conventionally, a solder resist used for such a printed wiring board is generally formed by patterning a thermosetting composition or a photocurable composition by a screen printing method, and thermosetting or photocuring a transfer portion. However, due to the high density of printed wiring boards and environmental problems, alkali-developing solder resists have become mainstream (see Japanese Patent Application Laid-Open No. 61-243869).
[0003]
Flexible printed circuit boards and TAB tapes are also used for electronic devices with a small space such as the connection between the main unit of a notebook computer and the display, the connection of movable parts such as the connection between the printer head and the main unit, and cameras and other devices with a small space. Has become indispensable. Solder resists used for such flexible printed wiring boards and TAB tapes are required to have coating properties such as bending resistance, folding resistance, flexibility, plating resistance, heat resistance, and electrical properties. In particular, warpage due to curing shrinkage of the solder resist is likely to cause a problem during transportation and mounting of the flexible printed wiring board, and therefore, it is required that the warpage be as small as possible.
[0004]
From such demands, conventionally, an alkali-developing photocurable resin using a photosensitive prepolymer obtained by esterifying a polyfunctional epoxy resin having a bisphenol skeleton with (meth) acrylic acid and then adding an acid anhydride. A thermosetting composition has been proposed (see JP-A-9-54434).
However, such a conventional technique has a problem that, since the linear polymer is used, the bend resistance is excellent, but the developability is poor. In particular, the flexible printed wiring board and the TAB tape tend not to transmit the spray pressure at the time of development due to the softness of the base material, so that the development residue tends to be easily generated.
On the other hand, when the molecular weight of the photosensitive prepolymer is reduced, although the developability is improved, sufficient bending resistance, folding resistance, and flexibility cannot be obtained, and from the viewpoint of dryness to the touch. There is a problem that photopolymerizable monomers cannot be used extensively and sensitivity decreases.
[0005]
Further, a reaction product of a novolak-type phenol resin and an alkylene oxide is reacted with an unsaturated monocarboxylic acid, and an alkali using a carboxyl group-containing photosensitive resin obtained by reacting the obtained reaction product with an acid anhydride. A photocurable / thermosetting composition that can be developed has been proposed (see Japanese Patent Application No. 2000-332850). However, an ether bond formed by adding an alkylene oxide to impart flexibility tends to reduce water resistance. When the amount of (meth) acrylic acid is increased in order to increase the sensitivity, the amount of acid anhydride to be added for dissolving in an aqueous alkaline solution is reduced, and the developability and the dryness to the touch tend to decrease. .
[0006]
Furthermore, a roll-to-roll method is used for the production of flexible printed wiring boards and TAB tapes, and a dry film type is used in view of workability, reliability, film thickness accuracy, and smoothness. Is required. Such a dry film type solder resist is supplied in the form of a sheet or a roll, and it is necessary to include a resin component having excellent flexibility and film forming property in the resin composition due to its characteristics in the form.
[0007]
[Problems to be solved by the invention]
Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, and its main purpose is to provide a high sensitivity and a bending resistance required for a solder resist used for a flexible printed wiring board or a TAB tape. Photo-curable / thermo-curable resin composition having excellent heat resistance, folding resistance, flexibility, plating resistance, heat resistance, and electrical properties, and the above-mentioned composition or a molded product thereof, applied, dried or laminated, and then activated. It is an object of the present invention to provide a cured product obtained by energy beam irradiation and heat curing.
Another object of the present invention is to provide a dry film having the above-described characteristics required for a solder resist used for a flexible printed wiring board or a TAB tape, and further having excellent workability, reliability, film thickness accuracy, and smoothness. An object of the present invention is to provide a photo-curable / thermo-curable resin composition having excellent processability and a molded product thereof.
[0008]
[Means for Solving the Problems]
To achieve the above object, according to the present invention, (A) (a) a linear polyfunctional epoxy compound represented by the following general formula (1)
Embedded image

(Where R ¹ , R ² Represents a hydrogen atom or a methyl group; ³ Represents a hydrogen atom or a glycidyl group, and n represents a value of 1 to 20. )
(B) a carboxyl group-containing photocurable resin obtained by reacting (b) an unsaturated monocarboxylic acid and then (c) a polybasic acid anhydride;
(B) (d) A compound having three or more phenolic hydroxyl groups in one molecule, (e) alkylene oxide is added, and the resulting alcoholic hydroxyl group is partially esterified with (b) an unsaturated monocarboxylic acid. Carboxyl group-containing photocurable resin obtained by adding (c) a polybasic acid anhydride to unreacted alcoholic hydroxyl groups,
A photocurable / thermosetting resin composition comprising (C) a photopolymerization initiator, (D) an epoxy resin having two or more epoxy groups in one molecule, and (E) a diluent. Is provided.
Further, according to the present invention, there is provided an electronic component comprising a flexible printed wiring board or a TAB tape, wherein an insulating layer is formed using the above composition.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
The present inventors have conducted intensive studies to achieve the above object, and have found that (A) (a) a linear polyfunctional epoxy compound represented by the following general formula (1)
Embedded image

(Where R ¹ , R ² Represents a hydrogen atom or a methyl group; ³ Represents a hydrogen atom or a glycidyl group, and n represents a value of 1 to 20. )
(B) a carboxyl group-containing photocurable resin obtained by reacting (b) an unsaturated monocarboxylic acid and then (c) a polybasic acid anhydride;
(B) (d) A compound having three or more phenolic hydroxyl groups in one molecule, (e) alkylene oxide is added, and the resulting alcoholic hydroxyl group is partially esterified with (b) an unsaturated monocarboxylic acid. Carboxyl group-containing photocurable resin obtained by adding (c) a polybasic acid anhydride to unreacted alcoholic hydroxyl groups,
A composition containing (C) a photopolymerization initiator, (D) an epoxy resin having two or more epoxy groups in one molecule, and (E) a diluent has high sensitivity, and is a flexible printed wiring board or TAB. Excellent photocuring and thermosetting properties required for solder resists used for tapes, excelling in bending resistance, folding resistance, flexibility, plating resistance, heat resistance, electrical properties, and excellent workability into dry films The present invention was found to be a composition, and the present invention was completed.
That is, the photocurable / thermosetting resin composition of the present invention uses the carboxyl group-containing photocurable resin (B) as an emulsifier and a photosensitive prepolymer to form the carboxyl group-containing photocurable resin. The resin (A) alone provides insufficient developability while maintaining other properties. As described above, by improving the developability, the molecular weight of the carboxyl group-containing photocurable resin (A) can be increased, and the sensitivity is improved, and the bending resistance, folding resistance, and flexibility are improved. Became possible.
[0010]
Hereinafter, each component of the photocurable and thermosetting resin composition of the present invention will be described in detail.
First, as the carboxyl group-containing photocurable resin (A), (a) a linear polyfunctional epoxy compound represented by the following general formula (1):
Embedded image

(Where R ¹ , R ² Represents a hydrogen atom or a methyl group; ³ Represents a hydrogen atom or a glycidyl group, and n represents a value of 1 to 20. )
Then, a resin obtained by reacting (b) an unsaturated monocarboxylic acid and then (c) a polybasic acid anhydride is used.
Specifically, the polyfunctional epoxy compound represented by the general formula (1) is a compound represented by the general formula (1) ³ Are hydrogen atoms and the value of n is 1 to 20. A bisphenol F-type or bisphenol A-type bifunctional epoxy compound is dissolved in a polar solvent such as dimethyl sulfoxide and the like, and epihalohydrin (eg, epichlorohydrin) and alkali metal water are dissolved. It is a resin having a bisphenol skeleton that is polyfunctionalized by reacting an oxide (eg, sodium hydroxide).
When the value of n in the general formula (1) is less than 1, it is not preferable because the dryness to the touch, the film forming property when forming a dry film and the crack resistance are reduced. On the other hand, when n exceeds 20, the developing property is lowered and the resolution cannot be obtained, which is not preferable. The average amount of epihalohydrin added is preferably at least 50%, more preferably at least 80%. If the added amount of epihalohydrin is less than 50%, development resistance upon photosensitization is hardly obtained, and water resistance is undesirably reduced.
The reaction product of the polyfunctional epoxy compound (a) thus obtained and the unsaturated monocarboxylic acid (b) is reacted with the polybasic acid anhydride (c) to obtain a carboxyl group-containing compound. The photocurable resin (A) is obtained.
[0011]
The unsaturated monocarboxylic acid (b) is for imparting radical polymerizability (photocurability) to the polyfunctional epoxy compound (a), and includes, for example, acrylic acid, methacrylic acid, crotonic acid, and cinnamic acid. , Β-acryloxypropionic acid and the like. Further, a reaction product of a compound having one hydroxy group and one or more (meth) acryloyl groups with a dibasic acid anhydride can also be used. Of these, acrylic acid and methacrylic acid are particularly preferred. These can be used alone or in combination of two or more.
The amount of the unsaturated monocarboxylic acid (b) to be added is 0.8 to 1.2 equivalents per equivalent of the epoxy group of the polyfunctional epoxy compound. When the addition amount of the unsaturated monocarboxylic acid (b) is less than 0.8 equivalent, unreacted epoxy groups remain and react with carboxyl groups derived from the polybasic acid anhydride to be added next, resulting in gelation. And storage stability is undesirably reduced. On the other hand, if the added amount exceeds 1.2 equivalents, undesired unsaturated monocarboxylic acid is not preferable because it causes a problem of odor and deteriorates coating film properties.
[0012]
Examples of the polybasic acid anhydride (c) include maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methyltetrahydrophthalic anhydride. , Methylhexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, dodecenylsuccinic anhydride, chlorendic anhydride, trimellitic anhydride, pyromellitic anhydride, 5- (2,5-di (Oxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, benzophenonetetracarboxylic anhydride, etc., and these can be used alone or in combination of two or more. Among these, alicyclic dibasic acids such as tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylendmethylenetetrahydrophthalic anhydride, and endmethylenetetrahydrophthalic anhydride Anhydrides are particularly preferred in terms of developability and curability.
The addition amount of the polybasic acid anhydride (c) is preferably in a range where the acid value of the carboxyl group-containing photocurable resin (A) is 60 to 120 mgKOH / g. If the acid value of the carboxyl group-containing photocurable resin is less than 60 mgKOH / g, it is not preferable because developability cannot be obtained. On the other hand, if the acid value exceeds 120 mgKOH / g, the coating properties such as plating resistance are undesirably reduced.
[0013]
The carboxyl group-containing photocurable resin (B) is obtained by adding an alkylene oxide (e) to a compound (d) having three or more phenolic hydroxyl groups in one molecule, and partially converting the resulting alcoholic hydroxyl group. It is obtained by esterifying with an unsaturated monocarboxylic acid (b) and further adding a polybasic acid anhydride (c) to an unreacted alcoholic hydroxyl group.
That is, by adding an alkylene oxide (e) to a compound (d) having three or more phenolic hydroxyl groups in one molecule, a polyether having an alcoholic hydroxyl group at a position with a high degree of freedom away from the main skeleton Polyols can be synthesized. By partially esterifying the alcoholic hydroxyl group of this polyether polyol with the unsaturated monocarboxylic acid (b), photocurability can be imparted. Furthermore, by reacting the above-mentioned polybasic acid anhydride (d) with the remaining alcoholic hydroxyl group, a carboxyl group can be introduced and alkali solubility can be obtained.
[0014]
Examples of the compound (d) having three or more phenolic hydroxyl groups in one molecule include tris (hydroxyphenyl) methane, tetra (hydroxyphenyl) ethane, phenol novolak resin, cresol novolak resin, and alkyl-modified phenol novolak resin. Known and commonly used resins such as bisphenol A novolak type resin, dicyclopentadiene type phenol resin, ziloc resin, copna resin, terpene phenol modified phenol resin and polyvinyl phenol can be used alone or in combination of two or more.
In the case of a compound having less than 3 phenolic hydroxyl groups in the compound (d), the number of photosensitive groups in the resulting carboxyl group-containing photocurable resin is small, and it is difficult to make the resin three-dimensional even with photocuring, and a development resistance is obtained. It is not preferable because it is no longer possible.
[0015]
Examples of the alkylene oxide (e) include ethylene oxide, propylene oxide, butylene oxide, ibutylene oxide, trimethylene oxide, tetrahydrofuran, and tetrahydropyran. Among these, ethylene oxide and propylene oxide are preferred from the viewpoint of flexibility and ease of reaction, and more preferably propylene oxide having good water resistance is used.
The addition amount of the alkylene oxide (e) is 1.0 to 10.0 mol per 1 mol of the phenolic hydroxyl group of the compound (d) having three or more phenolic hydroxyl groups in one molecule. When the addition amount of the alkylene oxide (e) is less than 1.0 mol per 1 mol of the phenolic hydroxyl group, esterification with the unsaturated monocarboxylic acid (b) or addition reaction of the polybasic anhydride (c) occurs. A difficult phenolic hydroxyl group remains, and it is not preferable because flexibility and the like are hardly obtained. On the other hand, when the added amount exceeds 10.0 mol, water resistance and dryness to the touch become difficult to obtain, which is not preferable. .
[0016]
The unsaturated monocarboxylic acid (b) and the polybasic anhydride (c) used in the synthesis of the carboxyl group-containing photocurable resin (B) were those used for the carboxyl group-containing photocurable resin (A). The same as described above is used.
The addition amount of the polybasic acid anhydride (c) is preferably in the range where the acid value of the carboxyl group-containing photocurable resin (B) is 20 to 120 mgKOH / g. When the acid value of the carboxyl group-containing photocurable resin (B) is less than 20 mgKOH / g, it is not preferable because developability with an aqueous alkali solution cannot be obtained. On the other hand, if the acid value exceeds 120 mgKOH / g, the amount of the photocurable group added is reduced, and the sensitivity is undesirably reduced.
Specifically, the unsaturated monocarboxylic acid (b) and the polybasic anhydride (B) are added to the alcoholic hydroxyl group of the polyol compound derived from the compound (d) having three or more phenolic hydroxyl groups in one molecule. Preferably, c) is reacted in the range of 8: 2 to 4: 6.
[0017]
Examples of the photopolymerization initiator (C) include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, Acetophenones such as 2-diethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2 Aminoacetophenones such as -dimethylamino-1- (4-morpholinophenyl) -butan-1-one, N, N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, -Black Anthraquinones such as anthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone; Benzophenones such as 4,4'-bisdiethylaminobenzophenone or xanthones; 2,4,6-trimethylbenzoyldiphenylphosphine oxide; These known and commonly used photopolymerization initiators can be used alone or as a mixture of two or more thereof. Further, N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-acid Photoinitiating aids such as tertiary amines such as dimethylaminobenzoate, triethylamine and triethanolamine can be added. In addition, a titanocene compound such as CGI-784 (manufactured by Ciba Specialty Chemicals) which absorbs in the visible light region can also be added to promote the photoreaction. Particularly preferred photopolymerization initiators are 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -Butan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like, but are not particularly limited thereto, and absorbs light in an ultraviolet light or visible light region and has a (meth) acryloyl group and the like. Not only the photopolymerization initiator and the photoinitiator but also those which radically polymerize the unsaturated group of the above can be used alone or in combination of two or more.
[0018]
The compounding amount of the photopolymerization initiator (C) is 0.1 to 100 parts by mass of the total amount of the carboxyl group-containing photocurable resins (A) and (B) (the same applies hereinafter as solid content). A ratio of 25 parts by mass, preferably 0.5 to 20 parts by mass is desirable. When the compounding amount of the photopolymerization initiator (C) is less than the above range, the composition does not cure even when irradiated with active energy rays, or the irradiation time needs to be increased, so that it is difficult to obtain appropriate coating film properties. . On the other hand, even if the photopolymerization initiator is added in a larger amount than the above range, there is no change in photocurability, which is not economically preferable.
[0019]
Examples of the epoxy resin (D) having two or more epoxy groups in one molecule include various commonly used epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, and brominated bisphenol. A type epoxy resin, hydrogenated bisphenol A type epoxy resin, biphenol type epoxy resin, bixylenol type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, tris (hydroxyphenyl) methane type epoxy resin, dicyclopentadiene skeleton Glycidyl ether compounds such as epoxy resin containing epoxy resin, brominated phenol novolak type epoxy resin, novolak type epoxy resin of bisphenol A; diglycidyl terephthalate, hexahydrophthalic acid Glycidyl ester compounds such as glycidyl ester and diglycidyl dimer acid; heterocyclic epoxy resins such as triglycidyl isocyanurate; N, N, N ', N'-tetraglycidyl meta-xylene diamine; N, N, N', N Glycidylamine compounds such as' -tetraglycidylbisaminomethylcyclohexane and N, N-diglycidylaniline; rubber-modified epoxy resins; alicyclic epoxy resins. These epoxy resins can be used alone or in combination of two or more.
[0020]
The epoxy resin (D) improves properties such as adhesiveness and heat resistance required for the solder resist by thermosetting. The compounding amount is 0.8 to 2.0 equivalents, preferably 1.0 to 1.6 equivalents, per equivalent of the carboxyl group of the carboxyl group-containing photocurable resins (A) and (B). . If the amount of the epoxy resin (D) is less than 0.8 equivalent, the moisture absorption, solder heat resistance, electric properties, etc. of the cured coating film are undesirably reduced. On the other hand, when the blending amount of the epoxy resin (D) exceeds 2.0 equivalents, the developability of the coating film and the plating resistance of the cured coating film deteriorate, and the crack resistance also decreases, which is not preferable.
[0021]
The photocurable and thermosetting resin composition of the present invention uses a solid or semi-solid carboxyl group-containing photocurable resin (A) or (B) in order to obtain dryness to the touch. Is dissolved, and the composition is adjusted to a viscosity suitable for a coating method, it is necessary to use a photopolymerizable monomer, an organic solvent, or the like as the diluent (E). Further, the photopolymerizable monomer can also enhance photocurability.
Examples of the photopolymerizable monomer used as the diluent (E) include hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; and glycols such as ethylene glycol, diethylene glycol, polyethylene glycol, and propylene glycol. Diacrylates; acrylamides such as N, N-dimethylacrylamide, N-methylolacrylamide, N, N-dimethylaminopropylacrylamide; aminoalkyls such as N, N-dimethylaminoethyl acrylate and N, N-dimethylaminopropyl acrylate Acrylates: hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, tricyclodecane dimethanol, Polyhydric alcohols such as s-hydroxyethyl isocyanurate or polyhydric acrylates such as an ethylene oxide adduct or propylene oxide adduct thereof; phenoxy acrylate, bisphenol A diacrylate, and ethylene oxide adduct or propylene of these phenols Acrylates such as oxide adducts; glycidyl ether acrylates such as glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, and triglycidyl isocyanurate; various urethane acrylates; and melamine acrylate, and / or Examples include methacrylates corresponding to acrylates. These photopolymerizable monomers can be used alone or in combination of two or more.
[0022]
Examples of the organic solvent used as the diluent (E) include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol and methyl carbitol. Glycol ethers such as butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; acetate ether, butyl acetate, and acetic acid ester of the above glycol ethers; Esters; alcohols such as ethanol, propanol, ethylene glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; Ether, petroleum naphtha, hydrogenated petroleum naphtha, and the like petroleum solvents such as solvent naphtha, as the photocurable resin (A) and (B) and good compatibility are preferred. Further, in forming a dry film, an organic solvent having a boiling point of 150 ° C. or less is preferable from the viewpoint of workability.
[0023]
The photo-curable and thermo-curable resin composition of the present invention suppresses curing shrinkage of a coating film, and improves properties such as printability, adhesion, and hardness.If necessary, barium sulfate and barium titanate are used. , Silicon oxide powder, finely divided silicon oxide, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, mica and other commonly used inorganic fillers and And / or organic fillers such as urethane beads can be blended alone or in combination of two or more. The compounding amount of the inorganic filler and / or the organic filler is 0 to 200 parts by mass, preferably 10 to 100 parts by mass per 100 parts by mass of the total amount of the carboxyl group-containing photocurable resins (A) and (B). Appropriate.
[0024]
In addition, the photocurable / thermosetting resin composition of the present invention may further include, if necessary, carbon black, titanium oxide, phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, naphthalene black, and the like. Known and commonly used colorants; known and commonly used thermal polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, pyrogallol, and phenothiazine; defoamers and / or leveling agents such as silicone, fluorine and polymer Known and commonly used additives such as an imidazole-based, thiazole-based, triazole-based, and silane coupling agent adhesion-imparting agent; and a curing catalyst such as dicyandiamide and melamine.
[0025]
The photo-curable and thermo-curable resin composition of the present invention having the composition as described above is diluted with the organic solvent or the like as necessary to adjust the viscosity to be suitable for the coating method. An organic solvent contained in the composition at a temperature of, for example, about 60 to 100 ° C. by applying to a flexible printed wiring board or TAB tape that has been made by a screen printing method, a curtain coating method, a spray coating method, a roll coating method, or the like. Is evaporated and dried to form a coating film.
[0026]
Alternatively, the composition can be formed into a dry film and laminated on a flexible printed wiring board or a TAB tape on which a circuit has been formed to form a coating film of a photocurable / thermosetting resin composition.
When forming a dry film, the photocurable and thermosetting resin composition of the present invention is diluted with the organic solvent to have an appropriate viscosity, and is applied and dried on a support film with a film coater or the like to form a dry film. Can be made. The coating thickness after drying is usually 10 to 50 μm, preferably 15 to 40 μm.
As a method of applying the above composition to the support film, for example, a knife coater application, a comma coater application, a die coater application, a gravure coater application, a roll coater application, a spray coater application, or the like can be used. Further, as the support film, for example, a film such as a polyester film such as a polyethylene terephthalate film, a polyamide imide film, a polypropylene film, a polystyrene film, or the like can be used.
[0027]
After the above composition is applied on a support film, the composition is usually dried at a temperature of 50 to 130 ° C. for 1 to 30 minutes to obtain a film. Further, it is desirable to laminate a peelable cover film on the surface of the film for the purpose of preventing dust from adhering to the surface of the film.
As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, surface-treated paper, or the like can be used. It is only necessary that the adhesive strength between the membrane and the cover film is smaller.
[0028]
Thereafter, the coating film prepared by any of the above methods can be selectively exposed to active energy rays through a photomask having a predetermined pattern, and the unexposed portion can be developed with a dilute alkaline aqueous solution to form a resist pattern. Furthermore, by performing heat curing after irradiation with active energy rays or irradiation with active energy rays after heat curing, or by final curing (main curing) only by heat curing, bending resistance, folding resistance, flexibility resistance, warpage, A cured film (for example, a solder resist film) having excellent plating resistance, heat resistance, and electrical properties can be formed.
[0029]
As the dilute aqueous alkali solution, a dilute aqueous alkaline solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, and amines can be used.
Further, as an irradiation light source for photocuring, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like is suitable. In addition, a laser beam or the like can be used as the active energy ray.
[0030]
【Example】
Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but it goes without saying that the present invention is not limited to the following Examples. In the following, “parts” and “%” are all based on mass unless otherwise specified.
[0031]
[Synthesis of photocurable resin (A) containing carboxyl group]
After dissolving 380 parts of bisphenol F type epoxy resin (epoxy equivalent = 950, softening point 85 ° C., average degree of polymerization n = 6.2) and 925 parts of epichlorohydrin in 462.5 parts of dimethyl sulfoxide, the purity is stirred at 70 ° C. 60.9 parts (1.5 mol) of 98.5% NaOH were added over 100 minutes. After the addition, the reaction was further performed at 70 ° C. for 3 hours. After the completion of the reaction, 250 parts of water was added and washed with water. After oil-water separation, most of the dimethyl sulfoxide and excess unreacted epichlorohydrin were recovered by distillation under reduced pressure from the oil layer, and the reaction product containing the remaining replication salt and dimethyl sulfoxide was dissolved in 750 parts of methyl isobutyl ketone, and further 30% NaOH 10 parts of an aqueous solution was added and reacted at 70 ° C. for 1 hour. After the completion of the reaction, the resultant was washed twice with 200 parts of water. After oil-water separation, til isobutyl ketone was distilled and recovered from the oil layer to obtain a polyfunctional epoxy compound (a) having an epoxy equivalent of 310 and a softening point of 69 ° C. When the obtained polyfunctional epoxy compound (a) was calculated from the epoxy equivalent, about 5 of the 6.2 alcoholic hydroxyl groups in the starting bisphenol F epoxy resin were epoxidized.
310 parts of this polyfunctional epoxy compound (a) and 282 parts of diethylene glycol monoethyl ether acetate were charged into a four-necked flask equipped with a stirrer and a reflux condenser, heated and stirred at 90 ° C., and dissolved. The obtained solution was once cooled to 60 ° C., and 72 parts of acrylic acid, 0.5 part of methylhydroquinone and 2 parts of triphenylphosphine were added, and the mixture was heated to 100 ° C. and reacted for about 60 hours. / G reaction was obtained. 140 parts of tetrahydrophthalic anhydride was added thereto, and the mixture was heated to 90 ° C., and reacted until the acid value of the solid content became 100 mgKOH / g, to obtain a solution containing 65% of the photocurable resin (B). Hereinafter, this solution is referred to as A-1 varnish.
[0032]
[Synthesis of photocurable resin containing carboxyl group (B)]
In an autoclave equipped with a thermometer, a nitrogen introducing device, an alkylene oxide introducing device, and a stirring device, 59 parts of cresol novolak resin (trade name “SHONOL CRG-951”, OH equivalent: 118) manufactured by Showa Polymer Co., Ltd., 50 2.6 parts of an aqueous sodium hydroxide solution and 50 parts of toluene / methyl isobutyl ketone (mass ratio = 2/1) were charged, the inside of the system was replaced with nitrogen while stirring, and then heated to 150 ° C., 9 kg / cm ² , 90 parts of propylene oxide were gradually introduced and reacted. Reaction is gauge pressure 0.0kg / cm ² After about 6 hours, the mixture was cooled to room temperature. Further, 3.0 parts of a 50% aqueous potassium hydroxide solution was added, the inside of the system was replaced with nitrogen, and the temperature was raised by heating to 150 ° C., 9 kg / cm. ² Gradually introduces 90 parts of propylene oxide at a gauge pressure of 0.0 kg / cm. ² After the reaction was continued until the temperature became, the mixture was cooled to room temperature. This reaction solution was neutralized with sodium hydroxide and potassium hydroxide added as catalysts with a 35% hydrochloric acid aqueous solution. Thereafter, the reaction product was diluted with toluene, washed three times with water, and the solvent was removed with an evaporator. The hydroxyl equivalent was 467 g / eq. Was obtained as an alkylene oxide adduct of a cresol novolak resin. In this case, an average of 6.0 moles of alkylene oxide was added to 1 mole of the phenolic hydroxyl group.
233.5 parts of an alkylene oxide adduct of the obtained cresol novolak resin, 25.2 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 part of hydroquinone monomethyl ether, and 100 parts of toluene were stirred with a stirrer and a thermometer. The reaction mixture was charged into a reactor equipped with an air blowing tube, stirred while blowing air, and reacted at 110 ° C. for 6 hours. After water generated by the reaction began to be distilled off as an azeotrope with toluene, the reaction was continued for another 5 hours and cooled to room temperature. The obtained reaction solution was washed with a 5% aqueous NaCl solution, toluene was distilled off with an evaporator, and diethylene glycol monoethyl ether acetate was added to obtain a cresol novolak skeleton acrylate resin solution having a nonvolatile content of 60%.
Next, into a four-necked flask equipped with a stirrer and a reflux condenser, 215.5 parts of the obtained acrylate resin solution having a cresol novolak skeleton, 0.05 parts of hydroquinone monomethyl ether, and 0.2 parts of triphenylphosphine were charged. This mixture was heated to 120 ° C., 11.4 parts of tetrahydrophthalic anhydride was added, reacted for 6 hours, cooled, and taken out. The carboxyl group-containing photocurable resin thus obtained had a nonvolatile content of 62% and a solid acid value of 30 mgKOH / g. Hereinafter, this reaction solution is referred to as B-1 varnish.
[0033]
(Synthesis of urethane acrylate resin)
In a flask equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser, 475 parts of a bisphenol A type epoxy resin (Epiclon 4050, manufactured by Dainippon Ink and Chemicals, Inc., epoxy equivalent = 950) and diethylene glycol monoethyl ether acetate 465 were added. A portion was weighed and dissolved by heating. Next, 0.1 part of hydroquinone as a polymerization inhibitor and 1.0 part of triphenylphosphine as a reaction catalyst were added. The mixture was heated to 95 to 105 ° C., and 36 parts of acrylic acid was gradually added dropwise, and reacted for about 16 hours until the acid value became 1.0 mgKOH / g or less. The reaction product was cooled to room temperature, 0.2 parts of dibutyltin dilaurate was added, the mixture was heated to about 70 ° C., and 186 parts of 2-methacryloyloxyethyl isocyanate was gradually added. The reaction was continued for about 6 hours until the absorption peak disappeared to obtain a solution of epoxy urethane acrylate having a nonvolatile content of 60%. Hereinafter, this solution is referred to as urethane varnish varnish.
[0034]
(Comparative Synthesis Example)
In a flask equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser, 210 parts of cresol novolak type epoxy resin (Epiclon N-680, manufactured by Dainippon Ink and Chemicals, Inc., epoxy equivalent = 210) and diethylene glycol monoethyl ether 96.4 parts of acetate was weighed out and dissolved by heating. Next, 0.1 part of hydroquinone as a polymerization inhibitor and 2.0 parts of triphenylphosphine as a reaction catalyst were added. The mixture was heated to 95 to 105 ° C., and 72 parts of acrylic acid was gradually added dropwise, and reacted for about 16 hours until the acid value became 3.0 mgKOH / g or less. The reaction product was cooled to 80 to 90 ° C., 76.1 parts of tetrahydrophthalic anhydride was added, and the absorption peak (1780 cm) of the acid anhydride was determined by infrared absorption analysis. ^-1 The reaction was carried out for about 6 hours until) disappeared. To this reaction liquid, 96.4 parts of an aromatic solvent ipsol # 150 manufactured by Idemitsu Petrochemical Co., Ltd. was added, diluted, and then taken out. The resin compound having two or more acryloyl groups and carboxyl groups thus obtained had a nonvolatile content of 65% and an acid value of solid of 78 mgKOH / g. Hereinafter, this reaction solution is referred to as R-1 varnish.
[0035]
(Examples 1-3 and Comparative Examples 1-3)
Using the A-1, B-1, R-1 varnish and urethane acrylate varnish obtained in the above synthesis example, the respective components were blended in the blend ratio shown in Table 1, and kneaded using a three-roll mill. Photocurable and thermosetting resin compositions were prepared.
[0036]
[Table 1]

[0037]
(1) Dry film formability
Each composition obtained as described above was applied to a 38 μm-thick PET film using a knife coater to a dry film thickness of 35 μm, and then dried at 110 ° C. for 5 minutes. A dry film of the product was obtained.
After the dry film of each composition was wound up on a roll, the state of the surface of the dry coating film was checked for the occurrence of cracks and the like using a loupe, and evaluated as follows.
：: No crack or the like is generated at all.
Δ: Some fine cracks occurred.
X: Cracks occur and peeling occurs.
[0038]
(2) Developability
The photo-curable and thermo-curable resin compositions of the above Examples and Comparative Examples were applied on the entire surface of the patterned copper foil substrate by screen printing, dried at 80 ° C. for 30 minutes, and allowed to cool to room temperature. , 1% Na at 30 ° C ₂ CO ₃ Spray pressure of aqueous solution 2kg / cm ² The development was performed for 30 seconds under the conditions described above, and the presence or absence of development residue of the dried coating film was visually confirmed. The criteria are as follows.
：: Completely developed.
Δ: Part of the coating film remains.
X: The coating film remains completely.
[0039]
(3) Sensitivity
Each composition obtained as described above was printed on the entire surface of a polyimide flexible printed wiring board by a screen printing method so as to have a dry film thickness of about 20 μm, and dried at 80 ° C. for 20 minutes in a hot air circulation type drying furnace. And an evaluation substrate was produced. A Kodak No. Apply 2 step tablet, 300mJ / cm ² Exposure at 2kg / cm spray pressure ² 1wt% Na ₂ CO ₃ The film was developed with an aqueous solution for 1 minute, and the number of steps at which the coating film was completely removed was evaluated.
[0040]
Each composition obtained as described above was printed on a polyimide flexible printed wiring board on which circuits were formed by a screen printing method so that a dry film thickness was about 20 μm, and was heated to 80 ° C. in a hot-air circulation drying oven. , Dried for 20 minutes. After this was cooled to room temperature, pattern exposure was carried out at an appropriate exposure amount such that the sensitivity of each composition became 6 steps, and the spray pressure was 2 kg / cm. ² 1wt% Na ₂ CO ₃ Developed in aqueous solution for 1 minute. This substrate was thermally cured at 150 ° C. for 60 minutes using a hot-air circulation type drying furnace to produce an evaluation substrate.
Hereinafter, using this evaluation substrate, warpage, bending resistance, solder heat resistance, and electroless gold plating resistance were evaluated.
[0041]
(4) Warpage
The evaluation substrate was cut into a square of 5 cm, the sample was placed on a horizontal place, and the amount of warpage was measured using a caliper.
：: Warpage is less than 1 mm.
Δ: The warpage is 1 mm or more and less than 3 mm.
X: The amount of warpage is 3 mm or more.
[0042]
(5) Flex resistance
The evaluation substrate was cut into a width of 1 cm and a length of 10 cm, and the coated surface was bent outward at 180 ° C., and the presence or absence of cracks was observed.
：: No abnormality at all.
Δ: Fine cracks are slightly observed.
×: Cracks reaching the base material are observed.
[0043]
(6) Solder heat resistance
A rosin-based flux was applied to the evaluation substrate and immersed in a solder bath set at 260 ° C. for 30 seconds. After washing the evaluation substrate with an organic solvent, a peeling test was performed using a cellophane tape, and the evaluation was made as follows.
：: No abnormality such as swelling, peeling or discoloration.
Δ: Only discoloration occurred.
×: Swelling or peeling occurred.
[0044]
(7) Electroless gold plating resistance
The evaluation substrate was subjected to electroless plating using commercially available electroless nickel plating solution and electroless gold plating solution.
A peel test using a cellophane adhesive tape was performed on the evaluation substrate after plating to evaluate the peeling of the resist layer.
：: No change was observed at all.
Δ: There is a slight change in peeling.
×: Peeling of the entire coating film.
[0045]
These results are summarized in Table 2.
[Table 2]

[0046]
【The invention's effect】
As described above, according to the photo-curable and thermo-curable resin composition of the present invention, it is highly sensitive and has the required bending resistance, folding resistance, flexibility, warpage, and bending resistance required for flexible printed wiring boards and TAB tapes. A coating film having excellent plating properties, heat resistance, electrical properties, and the like can be formed.
Further, since it has excellent dry film forming properties, it is possible to provide a dry film of a photo-curable / thermo-curable resin composition suitable for a roll-to-roll method.
Moreover, by applying and drying or laminating the photo-curable / thermo-curable resin composition of the present invention or a molded product thereof on a flexible printed wiring board or a TAB tape, irradiation with active energy rays and heat curing are performed. A cured product excellent in bending resistance, folding resistance, flexibility, plating resistance, heat resistance, and electrical properties is obtained, and a highly reliable flexible printed wiring board or TAB tape can be provided.

Claims (7)

(A) (a) A linear polyfunctional epoxy compound represented by the following general formula (1)

(In the formula, R ¹ and R ² represent a hydrogen atom or a methyl group, R ³ represents a hydrogen atom or a glycidyl group, and n represents a value of 1 to 20.)
(B) reacting an unsaturated monocarboxylic acid, and then (c) reacting a polybasic acid anhydride to obtain a carboxyl group-containing photocurable resin;
(B) (d) A compound having three or more phenolic hydroxyl groups in one molecule, (e) alkylene oxide is added, and the resulting alcoholic hydroxyl group is partially esterified with (b) an unsaturated monocarboxylic acid. Carboxyl group-containing photocurable resin obtained by adding (c) a polybasic acid anhydride to unreacted alcoholic hydroxyl groups,
A photocurable / thermosetting resin composition comprising (C) a photopolymerization initiator, (D) an epoxy resin having two or more epoxy groups in one molecule, and (E) a diluent. . The composition according to claim 1, wherein the acid value of the photocurable resin (B) is 20 to 120 mgKOH / g. The compound (d) having three or more phenolic hydroxyl groups in one molecule used for the photocurable resin (B) is a phenol novolak resin and / or a cresol novolak resin. 3. The composition according to 2. The amount of the alkylene oxide (e) added to the compound (d) having three or more phenolic hydroxyl groups in one molecule is 1.0 to 10.0 mol per 1 mol of the phenolic hydroxyl group. The composition according to any one of claims 1 to 3, characterized in that: The compounding amount of the photocurable resin (B) is 5 to 100 parts by mass per 100 parts by mass of the photocurable resin (A). Composition. A film-like molded product obtained by applying the composition according to any one of claims 1 to 5 to a support film and drying the composition. The composition or the molded product according to any one of claims 1 to 6, on a flexible printed wiring board or a TAB tape, applied, dried, or laminated, and then obtained by irradiation with active energy rays and heat curing. Cured product.