JPWO2002018313A1 - Oxetane-modified compounds, photocurable compounds derived therefrom, methods for their preparation and curable compositions containing them - Google Patents

Abstract

The phenolic hydroxyl group-containing compound (a) and the primary hydroxyl group-containing monofunctional oxetane compound (b) are converted into an alkali metal salt of an alkoxide, an alkali metal salt of a phenoxide, an alkali metal salt of a carboxylate, and a crown ether complex of these alkali metal salts. By reacting in the presence of at least one catalyst (c) selected from the group consisting of metal hydroxides and metal hydrides, oxetane-modified compounds can be synthesized in extremely high yields. A photocurable compound is obtained by reacting the obtained oxetane-modified compound with an ethylenically unsaturated compound (d) having a functional group that reacts with a hydroxyl group, and further reacting with a polybasic acid anhydride (e). Thereby, an alkali-soluble photocurable compound is obtained. These photocurable compounds are useful as photocurable components of photocurable compositions or photocurable and thermosetting compositions.

Description

前記反応式（１）において、Ｚはフェノール性水酸基含有化合物（ａ）の残基を示しており、フェノール性水酸基含有化合物（ａ）としては分子中に１つの水酸基を有する単官能の化合物でもよく、あるいは分子中に２つ以上の水酸基を有する多官能の化合物（もしくは樹脂）のいずれでもよい。
分子中に１つの水酸基を有するフェノール性水酸基含有化合物としては、例えばフェノール、クレゾール、ｐ−ヒドロキシスチレン等のフェノール及びその誘導体（飽和もしくは不飽和炭化水素基、ハロゲン原子、アリール基等の置換基を有するフェノール）が挙げられる。
分子中に２つの水酸基を有するフェノール性水酸基含有化合物としては、例えばビスフェノールＡ、ビスフェノールＦ、ビスフェノールＳ、臭素化ビスフェノールＡ、ビフェノール、ビキシレノール、カテコール、レゾルシン、ハイドロキノン、１，４−ナフタレンジオール、１，５−ナフタレンジオール等が挙げられる。
また、分子中に３つ以上の水酸基を有するフェノール性水酸基含有化合物としては、例えばフェノールノボラック、クレゾールノボラック、臭素化フェノールノボラック、ポリ（ヒドロキシスチレン）、カリックスアレーン類、２，４，４′−トリヒドロキシベンゾフェノン、４，４′，４″−メチリデントリスフェノール、トリ（ｐ−ヒドロキシフェニル）メチルメタン、トリ（ｐ−ヒドロキシフェニル）エチルメタン、シルセスキオキサン等のシリコーン樹脂類などが挙げられる。
また、単官能オキセタン化合物（ｂ）としては、前記反応式（１）中に示される一般式のＲ^１が水素原子又は炭素数１〜６のアルキル基である、一級水酸基を有する化合物を好適に用いることができる。アルキル基としては、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基、ｓｅｃ−ブチル基、ｔｅｒｔ−ブチル基、ｎ−ペンチル基、イソペンチル基、ネオペンチル基、ｎ−ヘキシル基、イソヘキシル基等の直鎖又は分岐鎖のアルキル基が挙げられる。これらの中でも、３−ヒドロキシメチルオキセタン、３−メチル−３−ヒドロキシメチルオキセタン、３−エチル−３−ヒドロキシメチルオキセタンが好ましい。
触媒（ｃ）としては、前記したようにアルコキシドのアルカリ金属塩、フェノキシドのアルカリ金属塩、カルボキシレートのアルカリ金属塩等のアルカリ金属塩（Ｋ塩、Ｎａ塩、Ｌｉ塩、Ｒｂ塩）、これらのクラウンエーテル錯体、金属水酸化物及び金属水素化物の少なくとも１種が用いられるが、これらの中でも塩基性の大きな塩が好ましい。例えば、ｔｅｒｔ−ブトキシカリウム塩、フェノキシカリウム塩、安息香酸カリウム塩の場合、この順に塩基性が小さくなるので、ｔｅｒｔ−ブトキシカリウム塩を用いることが好ましい。
クラウンエーテルとしては、例えば１２−クラウン−４、１５−クラウン−５、１８−クラウン−６、ジベンゾ−１８−クラウン−６、２１−クラウン−７、２４−クラウン−８等を用いることができる。
金属水酸化物の具体例としては、水酸化リチウムや水酸化ナトリウム、水酸化カリウムなどが挙げられる。
金属水素化物の具体例としては、水素化ナトリウムや水素化ホウ素ナトリウムなどが挙げられる。
さらに、後述するような１種又は２種以上の反応促進剤を併用することもでき、それによってさらに反応の進行を早めることができる。
前記反応において、フェノール性水酸基含有化合物（ａ）と単官能オキセタン化合物（ｂ）との仕込み量は、化学量論量でかまわないが、単官能オキセタン化合物（ｂ）の自己反応を防止するために、また反応速度を上げるために、単官能オキセタン化合物（ｂ）を過剰に使用することが望ましく、フェノール性水酸基含有化合物（ａ）１モルに対して単官能オキセタン化合物（ｂ）を１〜３モルの割合で使用することが好ましい。
一方、前記触媒（ｃ）の使用量は、フェノール性水酸基含有化合物（ａ）１モルに対して１〜３０モル％の割合が適当であり、好ましくは５〜２０モル％の割合である。前記触媒（ｃ）の使用量が１モル％未満の場合、充分に反応が進行し難くなり、一方、３０モル％を超えて過剰に使用しても、経済性の点で好ましくない。
反応条件としては、反応温度は１３０〜２００℃、好ましくは１５０〜１８０℃、反応時間は７２時間以下、好ましくは３０時間以下が適当である。反応温度が高くなる程、反応時間は短くて済み、例えば１８−クラウン−６／ｔｅｒｔ−ブトキシカリウム塩（１０モル％）を用いたｐ−クレゾール（１モル使用）と３−エチル−３−ヒドロキシメチルオキセタン（３モル使用）の反応は１６０℃で約１２時間、１８０℃で約３時間で反応は完結し、１００％の収率が達成できる。また、触媒の使用量を多くする程、反応時間は短くて済み、例えば１８−クラウン−６／ｔｅｒｔ−ブトキシカリウム塩を１０モル％用いた場合には１６０℃で約１２時間であったものが、２０モル％用いた場合には約４時間で反応は完結し、１００％の収率が達成できる。
さらに本発明者らの研究によれば、前記反応式（１）で得られるオキセタン変性化合物（Ａ）は、分子中に一級の水酸基を２つ有するため、分子中に少なくとも１つのエチレン性不飽和結合を有し、かつ水酸基と反応する１つの官能基を有する化合物（ｄ）、例えば不飽和モノカルボン酸を反応させることによって光硬化性化合物（Ａ’）を容易に得ることができ、さらに得られた光硬化性化合物（Ａ’）に多塩基酸無水物（ｅ）を反応させることによってアルカリ可溶性の光硬化性化合物（Ａ”）を容易に得ることができることを見出した。しかも、この光硬化性化合物（Ａ”）では一級の水酸基に対して多塩基酸無水物（ｄ）が結合したものであるため、結合部位が熱的に切断され難く、熱安定性に優れており、そのためこれを光硬化性成分として用いることにより、耐熱性、熱安定性に優れたアルカリ現像型の光硬化性・熱硬化性組成物を調製できることを見出した。
前記オキセタン変性化合物（Ａ）に、分子中に少なくとも１つのエチレン性不飽和結合を有し、かつ水酸基と反応する１つの官能基を有する化合物（ｄ）（以下、エチレン性不飽和化合物という。）を反応させて光硬化性化合物（Ａ’）を得る工程について説明すると、エチレン性不飽和基を有するペンダントとしては、ビニル基、アリル基、アクリロイル基、メタクリロイル基などがある。このようなペンダントを前記オキセタン変性化合物（Ａ）の一級水酸基に付加させる方法としては、不飽和モノカルボン酸の脱水エステル化反応、不飽和モノカルボン酸エステルのエステル交換反応や、不飽和モノカルボン酸クロライドを付加反応させる方法が一般的である。その反応工程を示せば、下記反応式（２）の通りである。

式中、Ｒ^１は前記したように水素原子又は炭素数１〜６のアルキル基を表わし、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ、水素原子、炭素数１〜６のアルキル基、アリール基、アラルキル基、シアノ基、フッ素原子、又はフリル基を表わし、Ｘは−ＯＨ、−ＯＲ、Ｃｌ、Ｂｒ又はＩを表わし、Ｒは炭素数１〜１２のアルキル基を表わす。
さらに、前記反応によって得られる光硬化性化合物（Ａ’）の残りの一級水酸基に多塩基酸無水物（ｅ）を付加させることによって、下記反応式（３）に従って側鎖にカルボキシル基を有するアルカリ可溶性の光硬化性化合物（Ａ”）を容易に得ることができる。

式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は前記と同じ意味であり、Ｙは多塩基酸無水物残基を表わす。
まず、エチレン性不飽和基の導入について説明すると、前記反応（２）に使用する不飽和モノカルボン酸の具体的な例としては、アクリル酸、メタクリル酸、ケイ皮酸、クロトン酸、ソルビン酸、α−シアノケイ皮酸、β−スチリルアクリル酸等が挙げられる。また、二塩基酸無水物と水酸基を有する（メタ）アクリレート類とのハーフエステルを用いてもよい。具体的には、フタル酸、テトラヒドロフタル酸、ヘキサヒドロフタル酸、マレイン酸、コハク酸等の無水物と、ヒドロキシエチルアクリレート、ヒドロキシエチルメタクリレート、ヒドロキシプロピルアクリレート、ヒドロキシプロピルメタクリレート等の水酸基含有（メタ）アクリレート類とのハーフエステルなどが挙げられる。これらの不飽和モノカルボン酸は単独で又は２種以上を組み合わせて使用してもよい。
また、不飽和モノカルボン酸エステルの具体的な例としては、上記不飽和モノカルボン酸のアルキルエステルが挙げられ、不飽和モノカルボン酸クロライドとしては、アクリル酸クロライド、メタクリル酸クロライドなどが挙げられる。
前記反応（２）におけるオキセタン変性化合物（Ａ）とエチレン性不飽和化合物（ｄ）との割合（反応混合物中の仕込み割合）は、オキセタン変性化合物（Ａ）／化合物（ｄ）の反応性官能基（カルボン酸等）の当量比が０．１以上であることが好ましく、より好ましくは０．３〜１．０である。上記当量比が０．１未満では、生成物中への重合性基の導入が不充分となるため、充分な光硬化性が得られず、従って充分な塗膜物性が得られないので好ましくない。一方、上記当量比が１．０を超えると未反応のエチレン性不飽和化合物（不飽和モノカルボン酸等）が残存するので好ましくない。なお、未反応のエチレン性不飽和化合物（ｄ）が残存した場合は、減圧留去、アルカリ洗浄などの周知の方法にて除去してもよい。
前記反応（２）は塩基性触媒の存在下で容易に進行する。この塩基性触媒としては、水酸化ナトリウム、水酸化カリウム、ピリジン、トリエチルアミンなど無機及び有機塩基のいずれも使用可能である。反応温度は、用いる反応溶剤の沸点を超えなければいかなる温度でも可能であるが、経済性を考慮すると約０℃〜１００℃の範囲が好ましい。より好ましくは、２０℃〜７０℃である。
なお、塩基性触媒の使用量は、オキセタン変性化合物（Ａ）１モルに対して０．１〜２５モル％の割合であることが望ましく、さらに好ましくは０．５〜２０モル％の割合であり、より好ましくは１〜１５モル％の割合である。塩基性触媒の使用量が０．１モル％よりも少ない割合の場合、反応によっては実用的な速度で反応が進行し難い場合があり、一方、２５モル％を超えて多量に存在しても顕著な反応促進効果は見られないため、経済性の点で好ましくない。
続いて多塩基酸無水物との反応について説明する。本発明では、上記のようにして生成した光硬化性化合物（Ａ’）中の一級水酸基の１化学当量に対して、多塩基酸無水物（ｅ）を０．１〜１．０モル反応させることにより、アルカリ可溶性の光硬化性化合物（光硬化性樹脂）（Ａ”）が製造される。光硬化性化合物（Ａ’）中には、不飽和モノカルボン酸等のエチレン性不飽和化合物（ｄ）と付加反応しなかった一級の水酸基が残存しており、この水酸基と多塩基酸無水物との付加反応によってカルボキシル基が導入さるためアルカリ可溶性となる。
多塩基酸無水物（ｅ）の具体例としては、無水フタル酸、無水コハク酸、オクテニル無水フタル酸、ペンタドデセニル無水コハク酸、無水マレイン酸、無水テトラヒドロフタル酸、ヘキサヒドロ無水フタル酸、メチルテトラヒドロ無水フタル酸、３，６−エンドメチレンテトラ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、テトラブロモ無水フタル酸、トリメリット酸などの二塩基酸無水物、あるいはビフェニルテトラカルボン酸二無水物、ナフタレンテトラカルボン酸二無水物、ジフェニルエーテルテトラカルボン酸二無水物、シクロペンタンテトラカルボン酸二無水物、無水ピロメリット酸、ベンゾフェノンテトラカルボン酸二無水物などの四塩基酸二無水物などが挙げられる。これらは単独で又は２種以上の混合物として用いることができる。
これらの多塩基酸無水物（ｅ）と光硬化性化合物（Ａ’）との反応は、前記の配合割合で約５０〜１５０℃、好ましくは８０〜１３０℃の温度範囲で行なうことが可能である。多塩基酸無水物の使用量は、光硬化性化合物（Ａ’）中の一級水酸基１化学当量に対して０．１〜１．０モルが好適である。多塩基酸無水物の使用量が０．１モルより少ないと、導入されるカルボキシル基の量が少なくなり、生成する樹脂に充分なアルカリ可溶性が付与されないので好ましくない。一方、１．０を超えて多量に使用すると、未反応の多塩基酸無水物が樹脂中に残存し、耐久性、電気特性などの特性を低下させるため好ましくない。
前記多塩基酸無水物（ｅ）と光硬化性化合物（Ａ’）との反応においては、反応促進剤として、前述の三級アミン、四級オニウム塩、三級ホスフィン、ホスホニウムイリド、クラウンエーテル錯体、及び三級アミンあるいは三級ホスフィンとカルボン酸又は酸性の強いフェノールとの付加体が使用可能である。その使用量は、多塩基酸無水物（ｅ）に対して０．１〜２５モル％の範囲が望ましく、さらに好ましくは０．５〜２０モル％であり、より好ましくは１〜１５モル％である。たたし、前述した不飽和モノカルボン酸等のエチレン性不飽和化合物（ｄ）との反応で用いた反応促進剤が系内に残存する場合には、新たに反応促進剤を添加しなくても反応を促進することが可能である。
前記オキセタン変性化合物（Ａ）とエチレン性不飽和化合物（ｄ）との反応及び光硬化性化合物（Ａ’）と多塩基酸無水物（ｅ）との反応は、有機溶媒の存在下又は無溶剤下のいずれでも進行するが、反応時の撹拌効果を改善するために後述する希釈剤の存在下で行なうことも可能である。なお、合成時の希釈剤として有機溶媒を用いた場合は、減圧蒸留など公知の方法にて溶媒を除去してもよい。
有機溶剤は、反応に悪影響を与えず、反応温度を維持できるものであれば公知のものが使用できる。具体的には、ジエチレングリコールモノメチルエーテル、ジエチレングリコールモノエチルエーテル、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モノブチルエーテル等のアルコール類、エチレングリコールモノメチルエーテルアセテート、ジエチレングリコールモノメチルエーテルアセテート、ジエチレングリコールモノエチルエーテルアセテート、プロピレングリコールモノメチルエーテルアセテート、ジプロピレングリコールモノメチルエーテルアセテート等のグリコールエステル類、ジエチレングリコールジメチルエーテル、ジプロピレングリコールジメチルエーテル等のエーテル類、メチルイソブチルケトン、シクロヘキサノン等のケトン類、トルエン（キシレン等の炭化水素類などが挙げられる。
また、前記オキセタン変性化合物（Ａ）とエチレン性不飽和化合物（ｄ）との反応及び光硬化性化合物（Ａ’）と多塩基酸無水物（ｅ）との反応において、不飽和二重結合の重合によるゲル化を防止する目的で、空気を吹き込んだり、重合禁止剤を加えてもよい。重合禁止剤の例としては、ハイドロキノン、トルキノン、メトキシフェノール、フェノチアジン、トリフェニルアンチモン、塩化銅などが挙げられる。
本発明の方法によって得られる前記光硬化性化合物（Ａ’）及びアルカリ可溶性の光硬化性化合物（Ａ”）は、活性エネルギー線の照射によりラジカルを発生する化合物、即ち光重合開始剤（Ｂ）及び必要に応じて希釈剤（Ｃ）を混合することにより、光硬化性組成物となり、さらにまた、分子中に少なくとも２つのオキシラン基又はオキセタニル基を有する熱硬化性化合物（Ｄ）を混合することにより光硬化性・熱硬化性組成物となり、その塗膜を露光・現像後に加熱することにより、硬化収縮を生じることなく、耐熱性、密着性、電気絶縁性、耐薬品性等に優れた硬化皮膜を形成することができる。特に、本発明の光硬化性・熱硬化性組成物がアルカリ可溶性の光硬化性化合物（Ａ”）を含有する場合、アルカリ水溶液による現像が可能である。
光重合開始剤（Ｂ）の具体例としては、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等のベンゾインとその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、４−（１−ｔ−ブチルジオキシ−１−メチルエチル）アセトフェノン等のアセトフェノン類；２−メチルアントラキノン、２−アミルアントラキノン、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−ジイソプロピルチオキサントン、２−クロロ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−（１−ｔ−ブチルジオキシ−１−メチルエチル）ベンゾフェノン、３，３′，４，４′−テトラキス（ｔ−ブチルジオキシカルボニル）ベンゾフェノン等のベンゾフェノン類；２−メチルチオ−１−［４−（メチルチオ）フェニル］−２−モルホリノ−プロパン−１−オンや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−オン等のアミノアセトフェノン類；２，４，６−トリメチルベンゾイルホスフィンオキシド等のアルキルホスフィン類；９−フェニルアクリジン等のアクリジン類などが挙げられる。
これらの光重合開始剤は、単独で又は２種以上の混合物として使用することが可能であり、その配合量は光硬化性化合物（Ａ’又はＡ”）１００質量部に対し、０．１〜３０質量部の割合が好ましい。０．１質量部より少ない場合は、活性エネルギー線の照射を行なっても硬化しない、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、３０質量部を超えて多量に添加しても光硬化性に変化はなく、経済的に好ましくない。
本発明の光硬化性組成物又は光硬化性・熱硬化性組成物においては、活性エネルギー線による硬化を促進させるために、増感剤を前記光重合開始剤と併用してもよい。併用しうる増感剤としては、トリエチルアミン、トリエタノールアミン、２−ジメチルアミノエタノール、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等の三級アミン類；β−チオジグリコール等のチオエーテル類；（ケト）クマリン、チオキサンテン等の増感色素類、及びシアニン、ローダミン、サフラニン、マラカイトグリーン、メチレンブルー等の色素のアルキルホウ酸塩などが挙げられる。これらの増感剤は、それぞれ単独でもしくは２種以上を混合して使用してもよい。その使用量は、前記光硬化性化合物（Ａ’又はＡ”）１００質量部に対し、０．１〜３０質量部の割合が好ましい。
さらに、本発明の光硬化性組成物又は光硬化性・熱硬化性組成物は、希釈剤を含有する。希釈剤（Ｃ）としては、前記したような有機溶剤の他、硬化反応に関与することができる重合性基を有する化合物、例えば単官能アクリレート類及び／又は多官能アクリレート類などの公知の反応性希釈剤が使用でき、それによって組成物の粘度調整の他に光硬化性を向上させることもできる。反応性希釈剤の具体的な例として、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ｎ−ブチル（メタ）アクリレート、イソブチル（メタ）アクリレート、２−エチルヘキシル（メタ）アクリレート、イソデシル（メタ）アクリレート、ラウリル（メタ）アクリレート、トリデシル（メタ）アクリレート、ステアリル（メタ）アクリレート、メトキシポリエチレングリコール（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、テトラヒドロフルフリル（メタ）アクリレート、イソボロニル（メタ）アクリレート、ベンジル（メタ）アクリレート、２−ヒドロキシエチル（メタ）アクリレート、２−ヒドロキレプロピル（メタ）アクリレート、２−ヒドロキシブチル（メタ）アクリレート、ジメチルアミノエチル（メタ）アクリレート、エチレングリコールジ（メタ）アクリレート、ジエチレングリコールジ（メタ）アクリレート、１，４−ブタンジオールジ（メタ）アクリレート、１，６−ヘキサンジオールジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート、グリセリンジ（メタ）アクリレート、ペンタエリスリトールトリ（メタ）アクリレート、ペンタエリスリトールテトラ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート、ポリエステルアクリレート、及び二塩基酸無水物と１分子中に少なくとも１個以上の不飽和基を有するアルコールとの反応物などを挙げることができる。希釈剤（Ｃ）は、単独で又は２種以上を混合して用いられ、その使用量は特に制限されるものではない。なお、本明細書中において、（メタ）アクリレートとは、アクリレート、メタクリレート及びそれらの混合物を総称する用語である（他の類似の表現についても同様）。
前記の１分子内に少なくとも２個のオキシラン基又はオキセタニル基を有する熱硬化性化合物（Ｄ）は、多官能のエポキシ化合物（Ｄ−１）又はオキセタン化合物（Ｄ−２）である。
多官能エポキシ化合物（Ｄ−１）としては、例えば、ノボラック型エポキシ樹脂（例えばフェノール、クレゾール、ハロゲン化フェノール、アルキルフェノールなどのフェノール類とホルムアルデヒドとを酸触媒下で反応させて得られるノボラック類に、エピクロルヒドリン及び／又はメチルエピクロルヒドリンを反応させて得られるものであり、市販品としては日本化薬（株）製のＥＯＣＮ−１０３、ＥＯＣＮ−１０４Ｓ、ＥＯＣＮ−１０２０、ＥＯＣＮ−１０２７、ＥＰＰＮ−２０１、ＢＲＥＮ−Ｓ；ダウ・ケミカル社製のＤＥＮ−４３１、ＤＥＮ−４３９；大日本インキ化学工業（株）製のＮ−７３０、Ｎ−７７０、Ｎ−８６５、Ｎ−６６５、Ｎ−６７３、Ｎ−６９５、ＶＨ−４１５０等）、ビスフェノールＡ型エポキシ樹脂（例えば、ビスフェノールＡ、ビスフェノールＦ、ビスフェノールＳ、テトラブロムビスフェノールＡなどのビスフェノール類にエピクロルヒドリン及び／又はメチルエピクロルヒドリンを反応させて得られるものや、ビスフェノールＡのグリシジルエーテルと前記ビスフェノール類の縮合物にエピクロルヒドリン及び／又はメチルエピクロルヒドリンを反応させて得られるもの等であり、市販品としては、油化シェルエポキシ（株）製のエピコート１００４、エピコート１００２；ダウ・ケミカル社製のＤＥＲ−３３０、ＤＥＲ−３３７等）、トリスフェノールメタン型エポキシ樹脂（例えば、トリスフェノールメタン、トリスクレゾールメタン等とエピクロルヒドリン及び／又はメチルエピクロルヒドリンを反応させて得られるものであり、市販品としては日本化薬（株）製のＥＰＰＮ−５０１、ＥＰＰＮ−５０２等）、トリス（２，３−エポキシプロピル）イソシアヌレート、ビフェニルグリシジルエーテル、その他脂環式エポキシ樹脂、アミノ基含有エポキシ樹脂、共重合型エポキシ樹脂、カルド型エポキシ樹脂、カリックスアレーン型エポキシ樹脂など公知慣用のエポキシ樹脂を単独で又は２種以上を組み合わせて用いることができる。
分子中に２つのオキセタン環を有する化合物の代表例としては、下記一般式（４）で示されるビスオキセタン類が挙げられる。

上記一般式（４）において、Ｒ^１は前記と同じ意味であり、Ｒ^５は、炭素数１〜１２の線状又は分岐状飽和炭化水素類、炭素数１〜１２の線状又は分岐状不飽和炭化水素類、下記式（Ａ）、（Ｂ）、（Ｃ）、（Ｄ）及び（Ｅ）で示される芳香族炭化水素類、式（Ｆ）及び（Ｇ）で示されるカルボニル基を含む直鎖状又は環状のアルキレン類、式（Ｈ）及び（Ｉ）で示されるカルボニル基を含む芳香族炭化水素類から選択される２つの原子価を持った基である。

式中、Ｒ^６は、水素原子、炭素数１〜１２のアルキル基、アリール基、又はアラルキル基を表わし、Ｒ^７は、−Ｏ−、−Ｓ−、−ＣＨ_２−、−ＮＨ−、−ＳＯ_２−、−ＣＨ（ＣＨ_３）−、−Ｃ（ＣＨ_３）_２−、又は−Ｃ（ＣＦ_３）_２−を表わし、Ｒ^８は、水素原子又は炭素数１〜６のアルキル基を表わす。

式中、ｎは１〜１２の整数を表わす。

分子中に３つ以上のオキセタン環を有する化合物の代表例としては、下記一般式（５）で示されるような化合物の他、オキセタンとノボラック樹脂、ポリ（ｐ−ヒドロキシスチレン）、カルド型オキセタン樹脂、カリックスアレーン類、カリックスレゾルシンアレーン、又はシルセスキオキサン等のシリコーン樹脂類などの水酸基を有する樹脂とのエーテル化物などが挙げられる。その他、オキセタン環を有する不飽和モノマーとアルキル（メタ）アクリレートとの共重合体等も挙げられる。

上記一般式（５）において、Ｒ^１は前記と同じ意味であり、Ｒ^９は、前記エーテル化物の水酸基含有樹脂残基、下記式（Ｊ）、（Ｋ）及び（Ｌ）で示されるような炭素数１〜１２の分岐状アルキレン基、式（Ｍ）、（Ｎ）及び（Ｐ）で示される芳香族炭化水素類である。また、ｍは残基Ｒ^９に結合している官能基の数を表わし、３以上の整数、好ましくは３〜５０００の整数である。

式中、Ｒ^１０は、水素原子、炭素数１〜６のアルキル基、又はアリール基を表わす。
前記したようなオキセタン化合物（Ｄ−２）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。
前記熱硬化性化合物（エポキシ化合物又はオキセタン化合物）（Ｄ）の配合量は、前記光硬化性化合物（Ａ’又はＡ”）１００質量部に対して５〜１００質量部の割合が適当であり、好ましくは１５〜６０質量部である。
また、解像性の点からは、前記希釈剤（Ｃ）に難溶性の微粒状のエポキシ化合物又はオキセタン化合物、あるいは難溶性のエポキシ化合物又はオキセタン化合物と可溶性のエポキシ化合物又はオキセタン化合物を組み合わせて用いることが好ましい。
さらに、熱硬化反応を促進するために、三級アミン類、四級オニウム塩類、三級ホスフィン類、クラウンエーテル錯体などや、イミダゾール誘導体、ジシアンジアミドなどの公知の硬化促進剤を少量併用することができる。硬化促進剤（Ｅ）としては、これらの中から任意に選択することが可能であり、これらを単独で又は２種以上混合して用いてもよい。その他、ホスホニウムイリドなど、公知の硬化促進剤を使用できる。
イミダゾール誘導体としては、イミダゾール、２−メチルイミダゾール、２−エチルイミダゾール、２−エチル−４−メチルイミダゾール、２−フェニルイミダゾール、４−フェニルイミダゾール、１−シアノエチル−２−フェニルイミダゾール、１−（２−シアノエチル）−２−エチル−４−メチルイミダゾールなどが挙げられる。具体的に市販されているものとしては、例えば四国化成（株）製の２ＭＺ−Ａ、２ＭＺ−ＯＫ、２ＰＨＺ、２Ｐ４ＢＨＺ、２Ｐ４ＭＨＺなどが挙げられる。また経時安定性向上を図るものとして、旭チバ（株）製のノバキュアＨＸ−３７２１、ＨＸ−３７４８、ＨＸ−３７４１、ＨＸ−３０８８、ＨＸ−３７２２、ＨＸ−３７４２、ＨＸ−３９２１ＨＰ、ＨＸ−３９４１ＨＰ、ＨＸ−３６１３等も挙げられる。
硬化促進剤（Ｅ）の使用量は、オキシラン基又はオキセタニル基１モルに対して０．１〜２５モル％の範囲であり、好ましくは０．５〜２０モル％であり、より好ましくは１〜１５モル％である。硬化促進剤の使用量が、オキシラン基／オキセタニル基に対して０．１モル％よりも少ないと実用的な速度で硬化反応が進行し難く、一方、２５モル％よりも多量に使用しても顕著な反応促進効果は見られないため、経済性の点で好ましくない。
ところで、多官能オキセタン化合物は多官能エポキシ化合物に比べて反応性が遅く安定しているため、これを含有する光硬化性・熱硬化性組成物はシェルフ・ライフ（保存寿命）が長く、一液型に組成することが可能となる。しかしながら、組成物調製から使用開始までに比較的時間を要する場合、前記のような熱硬化性成分を予め前記光硬化性・熱硬化性組成物に混合しておいた場合には回路板ブランクへの塗布前に増粘し易いので、使用に際して両者を混合して用いるのが望ましい。すなわち、前記多官能エポキシ化合物（Ｄ−１）又は多官能オキセタン化合物（Ｄ−２）を主体とした硬化剤溶液と、前記光硬化性化合物（Ａ’又はＡ”）を主体とし、これに前記硬化促進剤（Ｅ）等を配合した主剤溶液の二液型に組成し、使用に際してこれらを混合して用いることが好ましい。また、前記した光重合性モノマーや充填剤、着色顔料等を前記熱硬化性化合物（多官能エポキシ化合物又は多官能オキセタン化合物）の有機溶剤溶液に混合することもできる。
さらに、本発明の光硬化性組成物又は光硬化性・熱硬化性組成物には、硬化物の密着性、硬度、はんだ耐熱性などの特性を挙げる目的で、光反応性を損なわない範囲で、必要に応じて硫酸バリウム、酸化ケイ素、シリカ、タルク、クレー、炭酸カルシウムなどの公知慣用の充填剤、フタロシアニングリーン、フタロシアニンブルー、酸化チタン、カーボンブラックなどの公知慣用の着色顔料、消泡剤、密着性付与剤、レベリング剤などの各種添加剤類を加えてもよい。
上記のような各成分を配合して調製された硬化性組成物は、基板上に適当な方法で塗布し、活性エネルギー線の照射によって硬化させる。
例えば、レジストパターン形成の場合には、得られた光硬化性・熱硬化性組成物に前記したような希釈剤（Ｃ）を添加したりして所望の粘度に調整した後、回路形成されたプリント配線板等の基材上に、スクリーシ印刷法、カーテンコーティング法、ロールコーティング法、ディップコーティング法、スピンコーティング法などの適宜の塗布方法により塗布し、例えば約６０〜１２０℃の温度で仮乾燥することで組成物中に含まれる有機溶剤を除去し、タックフリーの塗膜を形成する。その後、所定の露光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る。さらに、例えば約１４０〜２００℃の温度で加熱して熱硬化させることにより、密着性、はんだ耐熱性、耐薬品性、電気絶縁性、耐電蝕性等の諸特性に優れた硬化塗膜が形成できる。またさらには、熱硬化前又は後にポストＵＶ硬化を行なうことにより、諸特性をさらに向上させることができる。
上記現像に用いるアルカリ水溶液としては、水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、炭酸カリウム、珪酸ナトリウム、アンモニア、有機アミン、テトラメチルアンモニウムハイドロオキシドなどの水溶液が使用できる。現像液中のアルカリの濃度は、概ね０．１〜５．０ｗｔ％であればよい。現像方式は、ディップ現像、パドル現像、スプレー現像など公知の方法を用いることができる。
本発明の光硬化性組成物又は光硬化性・熱硬化性組成物を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、メタルハライドランプなどが適当である。また、レーザー光線なども露光用活性光線として利用できる。その他、電子線、α線、β線、γ線、Ｘ線、中性子線なども利用可能である。
以下に実施例を示して本発明についてより具体的に説明するが、本発明はこれらの実施例に限定されるものではない。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。
実施例１（オキセタン変性化合物の合成）
ｐ−クレゾール１０．８ｇと１８−クラウン−６−エーテル２．６ｇ、カリウム−ｔｅｒｔ−ブトキシド１．２ｇをＮ−メチルピロリドン３０ｍｌに溶解し、室温で均一になるまで攪拌した。その後、３−エチル−３−ヒドロキシメチルオキセタン（東亞合成（株）製）３４．８ｇを加え、１６０℃で１２時間攪拌した。反応終了後、反応母液をシリカゲルクロマトグラフィー（展開溶媒；酢酸エチル：クロロホルム＝１：１）にかけ、その後、分取液体クロマトグラフィーにより単離精製し、オキセタン変性化合物Ａ−１として薄黄色の粘性液体を１９．８ｇ得た。収率は８８％であった。構造確認はＩＲスペクトル及び^１Ｈ−ＮＭＲにより行ない、下記化学式（６）に示す構造であることを確認した。得られたオキセタン変性化合物Ａ−１のＩＲスペクトルを図１に示す。

実施例２（光硬化性化合物の合成）
前記実施例１で得られたオキセタン変性化合物Ａ−１の５．６ｇと水酸化ナトリウム１．０ｇ、及び少量の重合禁止剤をメチルメタクリレート５０．０ｇに混合し、室温で４時間攪拌した。攪拌後、メチルメタクリレート及びメタノールを減圧留去し、残留物をクロロホルムに溶解して水洗を３回行なった。有機層を無水硫酸マグネシウムで乾燥後、クロロホルムを減圧留去し、光硬化性化合物Ａ’−１として黄色の粘性液体を１０．０ｇ得た。構造確認はＩＲスペクトル及び^１Ｈ−ＮＭＲにより行なった。得られた光硬化性化合物Ａ’−１のＩＲスペクトルを図２に示す。また、^１Ｈ−ＮＭＲより算出したエステル化率は６８．３％であった。
実施例３
前記実施例２で得られた光硬化性化合物Ａ’−１を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性化合物Ａ’−１　　　　　　　　　　　　　　　　　　２５部
イルガキュア１８４　　　　　　　　　　　　　　　　　　　　　５部
　　　　　（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
合　計　　　　　　　　　　　　　　　　　　　　　　　　　　３０部
得られた光硬化性組成物を銅板上に塗布し、紫外線照射装置（ウシオ電機（株）製ＵＩＳ−２５１０ＡＡ）により紫外線を１２０秒間照射したところ、タックフリーとなり、アセトンに不溶な皮膜が形成された。
実施例４（オキセタン変性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、ポリパラヒドロキシスチレン（丸善石油化学（株）製、商品名マルカリンカー）６０．０ｇ、３−エチル−３−ヒドロキシメチルオキセタン１７４．４ｇ、ｔ−ブトキシカリウム５．６ｇ、１８−クラウン−６−エーテル１３．７ｇ、及びＮ−メチルピロリドン３００ｍｌを加え、１４０℃にて６時間反応を行なった。反応混合物を大量の水に注ぎ、生成物を沈殿させた。生じた沈殿物をろ過により回収し、さらに少量のテトラヒドロフランに溶解させ、大量の水に注ぎ、再沈精製を行なった。得られた沈殿物を減圧下乾燥することで、下記化学式（７）で表わされる繰り返し単位を有するオキセタン変性樹脂Ａ−２を１０７ｇ得た。収率は９１％であった。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。得られたオキセタン変性樹脂Ａ−２のＩＲスペクトルを図３に示す。

実施例５（光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、前記実施例４で得られたオキセタン変性樹脂Ａ−２の５９．０ｇ、メチルメタクリレート２５０．０ｇ、水酸化カリウム３．３ｇ、及びテトラヒドロフラン３００ｍｌを加え、室温にて１２時間反応を行なった。反応混合物をクロロホルムに溶解し、水で３回洗浄した。有機層を硫酸マグネシウムで乾燥した後、ｎ−ヘキサンで再沈精製を行なうことで、不飽和二重結合が導入された光硬化性樹脂Ａ’−２を５９．６ｇ得た。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。得られた光硬化性樹脂Ａ’−２のＩＲスペクトルを図４に示す。また、^１Ｈ−ＮＭＲの積分比よりエステル化率は３５％であった。
実施例６（アルカリ可溶性の光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた５００ｍｌのフラスコに、前記実施例５で得られた光硬化性樹脂Ａ’−２の２００ｇ、テトラヒドロ無水フタル酸７６ｇ、トリフェニルホスフィン４ｇ、及びプロピレングリコールモノメチルエーテルアセテート１８３ｇを加え、８０℃にて３時間反応を行ない、カルボキシル基が導入された光硬化性樹脂Ａ”−２を６０％含む樹脂溶液を得た。ＩＲスペクトルより酸無水物の吸収が消失し、カルボン酸の水酸基に由来する幅広の吸収が現れたことを確認した。得られた光硬化性樹脂Ａ”−２のＩＲスペクトルを図５に示す。樹脂固形分の酸価は１００ｍｇＫＯＨ／ｇであった。また、この樹脂は、１％炭酸ナトリウム水溶液に可溶であった。
実施例７
前記実施例５で得られた光硬化性樹脂Ａ’−２を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ’−２　　　　　　　　　　　　　　　　　　　　３０部
イルガキュア１８４　　　　　　　　　　　　　　　　　　　　　　３部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ヒドロキシエチルメタクリレート　　　　　　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　０．３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　６３．３部
得られた光硬化性組成物を銅箔上に約１０μｍの膜厚に塗布し、紫外線照射装置（ウシオ電機（株）製ＵＩＳ−２５１０ＡＡ）にて紫外線を４８０秒間照射したところ、タックフリーとなり、アセトンに不溶な強固な皮膜が形成された。
実施例８
前記実施例６で得られた光硬化性樹脂Ａ”−２を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ”−２　　　　　　　　　　　　　　　　　　　１００部
イルガキュア９０７　　　　　　　　　　　　　　　　　　　　　１０部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ジペンタエリスリトールヘキサアクリレート　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　　　１部
ＴＥＰＩＣ（日産化学工業（株）製エポキシ樹脂）　　　　　　　３０部
２−フェニルイミダゾール　　　　　　　　　　　　　　　　　　　３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　　１７４部
上記光硬化性組成物を、銅箔上に約２５μｍの膜厚に塗布し、８０℃にて２０分間仮乾燥を行なった。この塗膜にフォトマスクを通して５００ｍＪ／ｃｍ^２の紫外線を選択的に照射した後、１％炭酸ナトリウム水溶液で１２０秒現像を行なったところ、未露光部が溶解除去され、画像が形成できた。さらに、現像後の塗膜を１５０℃にて３０分間加熱したところ、熱硬化反応が進行し、アセトン、テトラヒドロフランなどの有機溶媒に不溶な、より強固な皮膜が形成できた。
実施例９（オキセタン変性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、クレゾールノボラック樹脂６０．０ｇ、３−メチル−３−ヒドロキシメチルオキセタン６１．０ｇ、ｔ−ブトキシカリウム５．６ｇ、１８−クラウン−６−エーテル１３．７ｇ、及びＮ−メチルピロリドン３００ｍｌを加え、１６０℃にて６時間反応を行なった。反応混合物を大量の水に注ぎ、生成物を沈殿させた。生じた沈殿物をろ過により回収し、さらに少量のテトラヒドロフランに溶解させ、大量の水に注ぎ、再沈精製を行なった。得られた沈殿物を減圧下乾燥することで、目的とするオキセタン変性樹脂Ａ−３を１０７ｇ得た。収率は９１％、オキセタン付加率は１００％であった。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。得られたオキセタン変性樹脂Ａ−３のＩＲスペクトルを図６に示す。
実施例１０（光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、前記実施例９で得られたオキセタン変性樹脂Ａ−３の４４．４ｇ、メチルメタクリレート２００．０ｇ、水酸化カリウム３．３ｇ、及びテトラヒドロフラン３００ｍｌを加え、室温にて１２時間反応を行なった。反応混合物をクロロホルムに溶解し、水で３回洗浄した。有機層を硫酸マグネシウムで乾燥した後、ｎ−ヘキサンで再沈精製を行なうことで、不飽和二重結合が導入された光硬化性樹脂Ａ’−３を４８．０ｇ得た。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。得られた光硬化性樹脂Ａ’−３のＩＲスペクトルを図７に示す。また、^１Ｈ−ＮＭＲの積分比よりエステル化率は３５％であった。
実施例１１（アルカリ可溶性の光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた５００ｍｌのフラスコに、前記実施例１０で得られた光硬化性樹脂Ａ’−３の２００ｇ、テトラヒドロ無水フタル酸７６ｇ、トリフェニルホスフィン４ｇ、及びプロピレングリコールモノメチルエーテルアセテート１８３ｇを加え、８０℃にて３時間反応を行ない、カルボキシル基が導入された光硬化性樹脂Ａ”−３を６０％含む樹脂溶液を得た。ＩＲスペクトルより酸無水物の吸収が消失し、カルボン酸の水酸基に由来する幅広の吸収が現れたことを確認した。得られた光硬化性樹脂Ａ”−３のＩＲスペクトルを図８に示す。樹脂固形分の酸価は１００ｍｇＫＯＨ／ｇであった。また、この樹脂は、１％炭酸ナトリウム水溶液に可溶であった。
実施例１２
前記実施例１０で得られた光硬化性樹脂Ａ’−３を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ’−３　　　　　　　　　　　　　　　　　　　　３０部
イルガキュア１８４　　　　　　　　　　　　　　　　　　　　　　３部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ヒドロキシエチルメタクリレート　　　　　　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　０．３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　６３．３部
得られた光硬化性組成物を銅箔上に約１０μｍの膜厚に塗布し、紫外線照射装置（ウシオ電機（株）製ＵＩＳ−２５１０ＡＡ）にて紫外線を４８０秒間照射したところ、タックフリーとなり、アセトンに不溶な強固な皮膜が形成された。
実施例１３
前記実施例１１で得られた光硬化性樹脂Ａ”−３を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ”−３　　　　　　　　　　　　　　　　　　　１００部
イルガキュア９０７　　　　　　　　　　　　　　　　　　　　　１０部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ジペンタエリスリトールヘキサアクリレート　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　　　１部
ＴＥＰＩＣ（日産化学工業（株）製エポキシ樹脂）　　　　　　　３０部
２−フェニルイミダゾール　　　　　　　　　　　　　　　　　　　３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　　１７４部
上記光硬化性組成物を、銅箔上に約２５μｍの膜厚に塗布し、８０℃にて２０分間仮乾燥を行なった。この塗膜にフォトマスクを通して５００ｍＪ／ｃｍ^２の紫外線を選択的に照射した後、１％炭酸ナトリウム水溶液で１２０秒現像を行なったところ、未露光部が溶解除去され、画像が形成できた。さらに、現像後の塗膜を１５０℃にて３０分間加熱したところ、熱硬化反応が進行し、アセトン、テトラヒドロフランなどの有機溶媒に不溶な、より強固な皮膜が形成できた。
実施例１４（オキセタン変性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、クレゾールノボラック樹脂６０．０ｇ、３−メチル−３−ヒドロキシメチルオキセタン６１．０ｇ、ｔ−ブトキシカリウム５．６ｇ、及びＮ−メチルピロリドン３００ｍｌを加え、１６０℃にて６時間反応を行なった。反応混合物を大量の水に注ぎ、生成物を沈殿させた。生じた沈殿物をろ過により回収し、さらに少量のテトラヒドロフランに溶解させ、大量の水に注ぎ、再沈精製を行なった。得られた沈殿物を減圧下乾燥することで、目的とするオキセタン変性樹脂Ａ−４を８２．０ｇ得た。収率は６８％、オキセタン付加率は４７％であった。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。
実施例１５（オキセタン変性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、クレゾールノボラック樹脂６０．０ｇ、３−メチル−３−ヒドロキシメチルオキセタン６１．０ｇ、水酸化ナトリウム５．０ｇ、及びＮ−メチルピロリドン１５０ｍｌを加え、１６０℃にて６時間反応を行なった。反応混合物を大量の水に注ぎ、酸析を行なうことにより生成物を沈殿させた。生じた沈殿物をろ過により回収し、さらに少量のテトラヒドロフランに溶解させ、ｎ−ヘキサンに注ぎ、再沈精製を行なった。得られた沈殿物を減圧下乾燥することで、下記化学式（８）で表わされる繰り返し単位を有するオキセタン変性樹脂Ａ−５を１１０ｇ得た。収率は９１％、オキセタン付加率は１００％であった。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。得られたオキセタン変性樹脂Ａ−５のＩＲスペクトルを図９に示す。

実施例１６（オキセタン変性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、クレゾールノボラック樹脂６０．０ｇ、３−メチル−３−ヒドロキシメチルオキセタン６１．０ｇ、水酸化カリウム７．０ｇ、及びＮ−メチルピロリドン１５０ｍｌを加え、１６０℃にて６時間反応を行なった。反応混合物を大量の水に注ぎ、酸析を行なうことにより生成物を沈殿させた。生じた沈殿物をろ過により回収し、さらに少量のテトラヒドロフランに溶解させ、ｎ−ヘキサンに注ぎ、再沈精製を行なった。得られた沈殿物を減圧下乾燥することで、前記化学式（８）で表わされるオキセタン変性樹脂Ａ−５を得た。収率は９０％、オキセタン付加率は１００％であった。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。
実施例１７（光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた１０００ｍｌのフラスコに、前記実施例１５で得られたオキセタン変性樹脂Ａ−５の４４．４ｇ、メチルメタクリレート２００．０ｇ、水酸化カリウム３．３ｇ、及びテトラヒドロフラン３００ｍｌを加え、室温にて１２時間反応を行なった。反応混合物をクロロホルムに溶解し、水で３回洗浄した。有機層を硫酸マグネシウムで乾燥した後、ｎ−ヘキサンで再沈精製を行なうことで、不飽和二重結合が導入された光硬化性樹脂Ａ’−５を４８．０ｇ得た。その構造は、ＩＲスペクトル及び^１Ｈ−ＮＭＲにより確認した。また、^１Ｈ−ＮＭＲの積分比よりエステル化率は３５％であった。
実施例１８（アルカリ可溶性の光硬化性樹脂の合成）
還流冷却器、温度計、及び攪拌機を備えた５００ｍｌのフラスコに、前記実施例１７で得られた光硬化性樹脂Ａ’−５の２００ｇ、テトラヒドロ無水フタル酸７６ｇ、トリフェニルホスフィン４ｇ、及びプロピレングリコールモノメチルエーテルアセテート１８３ｇを加え、８０℃にて３時間反応を行ない、カルボキシル基が導入された光硬化性樹脂Ａ”−５を６０％含む樹脂溶液を得た。ＩＲスペクトルより酸無水物の吸収が消失し、カルボン酸の水酸基に由来する幅広の吸収が現れたことを確認した。樹脂固形分の酸価は１００ｍｇＫＯＨ／ｇであった。また、この樹脂は、１％炭酸ナトリウム水溶液に可溶であった。
実施例１９
前記実施例１７で得られた光硬化性樹脂Ａ’−５を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ’−５　　　　　　　　　　　　　　　　　　　　３０部
イルガキュア１８４　　　　　　　　　　　　　　　　　　　　　　３部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ヒドロキシエチルメタクリレート　　　　　　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　０．３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　６３．３部
得られた光硬化性組成物を銅箔上に約１０μｍの膜厚に塗布し、紫外線照射装置（ウシオ電機（株）製ＵＩＳ−２５１０ＡＡ）にて紫外線を４８０秒間照射したところ、タックフリーとなり、アセトンに不溶な強固な皮膜が形成された。
実施例２０
前記実施例１８で得られた光硬化性樹脂Ａ”−５を用い、以下に示す組成の光硬化性組成物を調製した。
光硬化性樹脂Ａ”−５　　　　　　　　　　　　　　　　　　　１００部
イルガキュア９０７　　　　　　　　　　　　　　　　　　　　　１０部
（チバ・スペシャルティー・ケミカルズ社製光重合開始剤）
ジペンタエリスリトールヘキサアクリレート　　　　　　　　　　３０部
シリコーン系消泡剤　　　　　　　　　　　　　　　　　　　　　　１部
ＴＥＰＩＣ（日産化学工業（株）製エポキシ樹脂）　　　　　　　３０部
２−フェニルイミダゾール　　　　　　　　　　　　　　　　　　　３部
合　計　　　　　　　　　　　　　　　　　　　　　　　　　　１７４部
上記光硬化性組成物を、銅箔上に約２５μｍの膜厚に塗布し、８０℃にて２０分間仮乾燥を行なった。この塗膜にフォトマスクを通して５００ｍＪ／ｃｍ^２の紫外線を選択的に照射した後、１％炭酸ナトリウム水溶液で１２０秒現像を行なったところ、未露光部が溶解除去され、画像が形成できた。さらに、現像後の塗膜を１５０℃にて３０分間加熱したところ、熱硬化反応が進行し、アセトン、テトラヒドロフランなどの有機溶媒に不溶な、より強固な皮膜が形成できた。
産業上の利用可能性
以上説明したように、本発明によって得られるオキセタン変性化合物（Ａ）は、分子中に一級の水酸基を２つ有するため、エチレン性不飽和化合物（ｄ）、例えば不飽和モノカルボン酸を反応させることによって光硬化性化合物（Ａ’）を容易に得ることができ、さらに得られた光硬化性化合物（Ａ’）に多塩基酸無水物（ｅ）を反応させることによってアルカリ可溶性の光硬化性化合物（Ａ”）を容易に得ることができ、これらを光硬化性成分として用いることにより、硬化収縮をそれ程生じることなく、短時間の活性エネルギー線の照射により速やかに硬化する光硬化性組成物が得られる。特に、上記光硬化性化合物（Ａ”）では一級の水酸基に対して多塩基酸無水物（ｄ）が結合したものであるため、結合部位が熱的に切断され難く、熱安定性に優れており、そのためこれを光硬化性成分として用いることにより、耐熱性、熱安定性に優れたアルカリ現像型の光硬化性・熱硬化性組成物を調製できる。また、露光・現像後の熱硬化により硬化収縮を生じることなく電気絶縁性、耐熱性、密着性、耐薬品性等に優れた硬化物が得られるため、プリント配線板の製造時に使用されるソルダーレジスト、エッチングレジスト、ビルドアップ基板用層間絶縁材、メッキレジスト、感光性ドライフィルム、ＰＤＰ蛍光体等の製造など、種々の技術分野において有用である。
【図面の簡単な説明】
図１は、実施例１で得られたオキセタン変性化合物Ａ−１のＩＲスペクトルである。
図２は、実施例２で得られた光硬化性化合物Ａ’−１のＩＲスペクトルである。
図３は、実施例４で得られたオキセタン変性樹脂Ａ−２のＩＲスペクトルである。
図４は、実施例５で得られた光硬化性樹脂Ａ’−２のＩＲスペクトルである。
図５は、実施例６で得られた光硬化性樹脂Ａ”−２のＩＲスペクトルである。
図６は、実施例９で得られたオキセタン変性樹脂Ａ−３のＩＲスペクトルである。
図７は、実施例１０で得られた光硬化性樹脂Ａ’−３のＩＲスペクトルである。
図８は、実施例１１で得られた光硬化性樹脂Ａ”−３のＩＲスペクトルである。
図９は、実施例１５で得られたオキセタン変性樹脂Ａ−５のＩＲスペクトルである。Technical field
The present invention relates to an oxetane-modified compound (a general term including a resin), a photocurable compound derived from the oxetane-modified compound (a general term including a photocurable resin), a process for producing the same, and a process for containing the same. Regarding the curable composition, more specifically, an oxetane-modified compound obtained from a compound having a phenolic hydroxyl group and a monofunctional oxetane compound having a primary hydroxyl group, which is obtained by introducing an ethylenically unsaturated group or further a carboxyl group Photo-curable compounds and solder resists containing them as photo-curable components and used in the manufacture of printed wiring boards, interlayer insulating materials for build-up boards, plating resists, etching resists, photosensitive dry films and PDP phosphors For photo-curable compositions or photo-curable / thermo-curable compositions used in manufacturing, etc. Is shall.
Background art
The curing of resins by irradiation with active energy rays is widely used in metal coating, wood coating, printing ink, electronic materials, etc. because of their high curing speed and no solvent. A material mainly used in these fields is epoxy acrylate. This compound is obtained by reacting an epoxy resin having an oxirane group, which is a three-membered cyclic ether, with (meth) acrylic acid, and has a (meth) acryloyl group. In addition, it has been used as a photocurable composition by mixing with, and various studies have been made so far. However, these compositions have a problem that adhesion to various substrates is inferior due to the large shrinkage after photocuring and the fact that the hydroxyl groups generated after the modification reaction are secondary hydroxyl groups.
In addition, in the soldering process performed when electronic components are mounted on a printed wiring board, solder resist is used to prevent solder adhesion to unnecessary parts and protect circuits. The development-type solder resist for forming is widely used, and the alkali-development type is mainly used in consideration of environment and cost. The base resin used in these development-type solder resists is an active energy ray obtained by reacting an epoxy resin with (meth) acrylic acid and then reacting a secondary hydroxyl group generated in the modified resin with an acid anhydride. Curable resins are commonly used.
By the way, with the increase in the density of ICs and LSIs, it has become necessary to reduce the circuit width and circuit interval of a printed wiring board. Furthermore, the operating frequency of these mounted components has been improved, and the amount of heat generated from the components has been increased, and printed wiring boards have been required to have higher thermal stability than ever before. However, in an active energy ray-curable resin starting from an epoxy resin, most of the functional groups binding to the acid anhydride are secondary hydroxyl groups, and the bond is likely to be broken when exposed to a high temperature for a long time. As a result, there are problems such as deterioration of properties such as insulation and heat resistance, and contamination of a circuit due to scattering of decomposed acid anhydride.
Recently, from the viewpoint of creating a new organic reaction and applying it to polymer synthesis, an organic reaction using a ring-opening addition reaction of an oxetane ring, which is a 4-membered ether, has been studied. For example, an oxetane compound and an active ester Reaction (T. Nishikubo {and} S. Kazuya, Chem. Lett., 697 (1992)), or synthesis of polyester having a primary hydroxyl group on the side chain by polyaddition reaction of bisoxetane and dicarboxylic acid (T. Nishikubo, A. Kamayama, A. Suzuki, Reactive & Functional Polymers, 37, 19 (1998)). More recently, polyaddition reactions between bisoxetanes and bisphenols (T. Nishikubo, A. Kamayama, M. Ito, T. Nakajima, H. Miyazaki, Journal of the Polymer, Chemistry, Vol. 371-p. (1998)), and tetraphenylphosphonium bromide (TPPB) or the like is used as a reaction catalyst. However, there are no reports on the oxetane-modified compounds of the present invention.
Therefore, the present inventors have found that when a phenol is reacted with an oxetane compound, what is produced by the ring-opening addition reaction of the oxetane ring is a primary hydroxyl group, which is reacted with an unsaturated monocarboxylic acid or the like to react with ethylenic acid. By introducing an unsaturated group, or by further reacting a polybasic acid anhydride to introduce a carboxyl group, there is no such a problem that occurs when an epoxy resin is used as a starting material, and in various fields. It has been found that useful photocurable compounds and alkali-soluble photocurable compounds can be synthesized. However, when a polyfunctional bisoxetane and a bisphenol are subjected to a polyaddition reaction using TPPB as a catalyst as described above, a polymer can be synthesized in a relatively high yield. However, a monofunctional oxetane compound is reacted with the phenol. Yields a very low yield. For example, the above-mentioned Journal of Polymer, Chemistry, Vol. 37 pp. 2781-2790 (1998) also reported that the yield when reacting 3- (benzyloxy) methyl-3-ethyloxetane with p-nitrophenol using TPPB as a catalyst for 48 hours was 29%. Have been.
Accordingly, a basic object of the present invention is to find a method capable of synthesizing an addition product in a very high yield when a phenolic hydroxyl group-containing compound is reacted with a monofunctional oxetane compound, and thus, a light-emitting material useful in various fields. An object of the present invention is to provide an oxetane-modified compound serving as a base compound of a curable compound or an alkali-soluble photocurable compound.
Another object of the present invention is to provide a method capable of easily introducing an ethylenically unsaturated group or a carboxyl group into such an oxetane-modified compound, and thus a photocurable compound useful as a photocurable component and further an alkali-soluble photocurable. To provide an active compound.
Furthermore, an object of the present invention is to provide a photocurable composition which is rapidly cured by irradiation with active energy rays for a short time, and provides a cured product excellent in adhesion to various substrates and other various properties, Another object of the present invention is to provide an alkali-developable photo-curable / thermo-curable composition capable of obtaining a cured coating film having excellent heat resistance and thermal stability.
Disclosure of the invention
According to a first aspect of the present invention, there is provided a compound (a) having a phenolic hydroxyl group and a compound (b) having one oxetane ring and one primary hydroxyl group in a molecule. An oxetane-modified compound (or oxetane-modified resin) comprising a reaction product is provided.
According to the present invention, there is also provided a method for producing such an oxetane-modified compound, which comprises a compound (a) having a phenolic hydroxyl group and a compound having one oxetane ring and one primary hydroxyl group in the molecule ( b) is at least one selected from the group consisting of alkali metal salts of alkoxides, alkali metal salts of phenoxides, alkali metal salts of carboxylates, crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides In the presence of the catalyst (c).
According to the method of the present invention, as the catalyst (c), a highly basic alkali metal salt composed of a combination of a weakly acidic acid and a strong base, a crown ether complex thereof, a metal hydroxide and a metal hydride Since oxetane is used, an oxetane-modified compound can be synthesized in a very high yield of 100% or close to it.
According to a second aspect of the present invention, a reaction between the oxetane-modified compound and a compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group A photocurable compound (or photocurable resin) comprising the product is also provided.
According to the present invention, there is also provided a method for producing such a photocurable compound, the method comprising:
A compound (a) having a phenolic hydroxyl group and a compound (b) having one oxetane ring and one primary hydroxyl group in a molecule are obtained by mixing an alkali metal salt of an alkoxide, an alkali metal salt of a phenoxide, an alkali metal salt of a carboxylate, Reacting in the presence of at least one catalyst (c) selected from the group consisting of crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides to obtain oxetane-modified compounds (A);
The resulting oxetane-modified compound (A) is reacted with the compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group. To obtain a photocurable compound (A ′) in which an unsaturated bond has been introduced into
It is characterized by including.
Further, according to a third aspect of the present invention, there is provided an alkali-soluble photocurable compound comprising a reaction product of the photocurable compound (A ') and a polybasic acid anhydride (e).
According to the present invention, there is also provided a method for producing such an alkali-soluble photocurable compound, the method comprising:
A compound (a) having a phenolic hydroxyl group and a compound (b) having one oxetane ring and one primary hydroxyl group in a molecule are obtained by mixing an alkali metal salt of an alkoxide, an alkali metal salt of a phenoxide, an alkali metal salt of a carboxylate, Reacting in the presence of at least one catalyst (c) selected from the group consisting of crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides to obtain oxetane-modified compounds (A);
The resulting oxetane-modified compound (A) is reacted with a compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group, to thereby form a photocurable compound ( Obtaining A ′), and
A step of reacting the obtained photocurable compound (A ′) with a polybasic acid anhydride (e) to obtain an alkali-soluble photocurable compound (A ″)
It is characterized by including.
Since the oxetane-modified compound (A) has two primary hydroxyl groups in the molecule, the photocurable compound (A ′) is reacted by reacting an ethylenically unsaturated compound (d), for example, an unsaturated monocarboxylic acid. The alkali-soluble photocurable compound (A ″) can be easily obtained by reacting the obtained photocurable compound (A ′) with the polybasic acid anhydride (e). In addition, by using these photocurable compounds (A ′ and / or A ″) as photocurable components, they can be rapidly cured by irradiation with active energy rays for a short time without causing significant curing shrinkage. A photocurable composition is obtained. In particular, in the photocurable compound (A "), since the polybasic acid anhydride (d) is bonded to the primary hydroxyl group, the bonding site is hardly cleaved and has excellent thermal stability. Therefore, by using this as a photocurable component, an alkali developable photocurable / thermosetting composition having excellent heat resistance and thermal stability can be prepared. A cured product excellent in electrical insulation, heat resistance, adhesion, chemical resistance and the like can be obtained without causing curing shrinkage.
Therefore, according to another aspect of the present invention, a light containing the photocurable compound (A ′ and / or A ″) as described above, a photopolymerization initiator and, if necessary, a diluent. A curable composition is provided.
Furthermore, a photocurable compound (A ′ or A ″) as described above, a photopolymerization initiator, a thermosetting compound having at least two oxirane groups or oxetanyl groups in the molecule, and a diluent as needed. A photo-curable / thermo-curable composition characterized by containing the composition.
BEST MODE FOR CARRYING OUT THE INVENTION
In the reaction of the phenolic hydroxyl group-containing compound (a) with a compound having one oxetane ring and one primary hydroxyl group in the molecule, that is, a monofunctional oxetane compound (b), Using at least one selected from the group consisting of alkali metal salts of alkoxides, alkali metal salts of phenoxides, alkali metal salts of carboxylate, crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides. It has been found that when reacted, an addition product can be synthesized in an extremely high yield of 100% or close to it. This was a surprisingly high yield from similar previously reported examples of reactions. An example of the above reaction is shown in the following reaction formula (1). The fact that the following reaction proceeds at an extremely high reaction rate of 100% or close means that a highly basic salt composed of a combination of a weakly acidic acid and a strong base, that is, an alkali metal salt or a crown thereof as described above, is used as a catalyst. This is considered to be due to the use of the ether complex, metal hydroxide and metal hydride.

In the reaction formula (1), Z represents a residue of the phenolic hydroxyl group-containing compound (a), and the phenolic hydroxyl group-containing compound (a) may be a monofunctional compound having one hydroxyl group in a molecule. Or a polyfunctional compound (or resin) having two or more hydroxyl groups in the molecule.
Examples of the phenolic hydroxyl group-containing compound having one hydroxyl group in the molecule include phenols such as phenol, cresol, and p-hydroxystyrene and derivatives thereof (substituents such as saturated or unsaturated hydrocarbon groups, halogen atoms, and aryl groups. Having phenol).
Examples of the phenolic hydroxyl group-containing compound having two hydroxyl groups in the molecule include bisphenol A, bisphenol F, bisphenol S, brominated bisphenol A, biphenol, bixylenol, catechol, resorcinol, hydroquinone, 1,4-naphthalenediol, , 5-naphthalene diol and the like.
Examples of the phenolic hydroxyl group-containing compound having three or more hydroxyl groups in the molecule include phenol novolak, cresol novolak, brominated phenol novolak, poly (hydroxystyrene), calixarenes, 2,4,4'-tri Examples thereof include silicone resins such as hydroxybenzophenone, 4,4 ', 4 "-methylidene trisphenol, tri (p-hydroxyphenyl) methylmethane, tri (p-hydroxyphenyl) ethylmethane, and silsesquioxane.
Further, as the monofunctional oxetane compound (b), R represented by the general formula shown in the above reaction formula (1) is used.¹Is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms and having a primary hydroxyl group. Examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, and n- A straight-chain or branched-chain alkyl group such as a hexyl group and an isohexyl group is exemplified. Among these, 3-hydroxymethyloxetane, 3-methyl-3-hydroxymethyloxetane, and 3-ethyl-3-hydroxymethyloxetane are preferred.
As the catalyst (c), as described above, alkali metal salts of alkoxides, alkali metal salts of phenoxides, alkali metal salts of carboxylate and the like (K salts, Na salts, Li salts, Rb salts); At least one of a crown ether complex, a metal hydroxide and a metal hydride is used, and among them, a salt having a large basicity is preferable. For example, in the case of potassium tert-butoxy, potassium phenoxy, and potassium benzoate, the basicity decreases in this order, and thus it is preferable to use potassium tert-butoxy.
As the crown ether, for example, 12-crown-4, 15-crown-5, 18-crown-6, dibenzo-18-crown-6, 21-crown-7, 24-crown-8 and the like can be used.
Specific examples of the metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide and the like.
Specific examples of the metal hydride include sodium hydride and sodium borohydride.
Furthermore, one or more reaction accelerators as described below can be used in combination, whereby the progress of the reaction can be further accelerated.
In the above reaction, the phenolic hydroxyl group-containing compound (a) and the monofunctional oxetane compound (b) may be charged in a stoichiometric amount, but in order to prevent a self-reaction of the monofunctional oxetane compound (b). In order to increase the reaction rate, the monofunctional oxetane compound (b) is desirably used in excess, and the monofunctional oxetane compound (b) is used in an amount of 1 to 3 mol per mol of the phenolic hydroxyl group-containing compound (a). Is preferably used.
On the other hand, the amount of the catalyst (c) to be used is appropriately 1 to 30 mol%, preferably 5 to 20 mol%, per 1 mol of the phenolic hydroxyl group-containing compound (a). When the amount of the catalyst (c) used is less than 1 mol%, the reaction does not easily proceed sufficiently. On the other hand, if it is used in excess of 30 mol%, it is not preferable in terms of economy.
Suitable reaction conditions are a reaction temperature of 130 to 200 ° C, preferably 150 to 180 ° C, and a reaction time of 72 hours or less, preferably 30 hours or less. The higher the reaction temperature, the shorter the reaction time. For example, p-cresol (1 mol used) using 18-crown-6 / tert-butoxy potassium salt (10 mol%) and 3-ethyl-3-hydroxy The reaction of methyloxetane (using 3 moles) is completed in about 12 hours at 160 ° C. and about 3 hours at 180 ° C., and a 100% yield can be achieved. In addition, as the amount of the catalyst used is increased, the reaction time is shortened. For example, when 10 mol% of 18-crown-6 / tert-butoxy potassium salt is used, the reaction time is about 12 hours at 160 ° C. , 20 mol%, the reaction is completed in about 4 hours, and a 100% yield can be achieved.
According to the study of the present inventors, the oxetane-modified compound (A) obtained by the above reaction formula (1) has two primary hydroxyl groups in the molecule, and therefore has at least one ethylenically unsaturated compound in the molecule. A photocurable compound (A ′) can be easily obtained by reacting a compound (d) having a bond and having one functional group that reacts with a hydroxyl group, for example, an unsaturated monocarboxylic acid, and further obtains the compound. It has been found that an alkali-soluble photocurable compound (A ″) can be easily obtained by reacting the obtained photocurable compound (A ′) with a polybasic acid anhydride (e). In the curable compound (A "), since the polybasic acid anhydride (d) is bonded to the primary hydroxyl group, the bonding site is hardly cleaved thermally and has excellent thermal stability. The light curable By using as a frequency it has been found that the heat resistance, thermal stability excellent alkali developing type photocurable and thermosetting composition can be prepared.
Compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group in the oxetane-modified compound (A) (hereinafter, referred to as an ethylenically unsaturated compound). The step of obtaining a photocurable compound (A ′) by reacting with a pendant is described below. Pendants having an ethylenically unsaturated group include a vinyl group, an allyl group, an acryloyl group, and a methacryloyl group. Examples of a method for adding such a pendant to the primary hydroxyl group of the oxetane-modified compound (A) include a dehydration esterification reaction of an unsaturated monocarboxylic acid, a transesterification reaction of an unsaturated monocarboxylic acid ester, and an unsaturated monocarboxylic acid. A method of performing an addition reaction with chloride is generally used. The reaction process is shown in the following reaction formula (2).

Where R¹Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms as described above;², R³And R⁴Represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group, an aralkyl group, a cyano group, a fluorine atom, or a furyl group, respectively, and X represents -OH, -OR, Cl, Br or I, R represents an alkyl group having 1 to 12 carbon atoms.
Further, by adding a polybasic acid anhydride (e) to the remaining primary hydroxyl group of the photocurable compound (A ′) obtained by the above reaction, an alkali having a carboxyl group in a side chain according to the following reaction formula (3). The soluble photocurable compound (A ″) can be easily obtained.

Where R¹, R², R³And R⁴Has the same meaning as described above, and Y represents a polybasic acid anhydride residue.
First, the introduction of an ethylenically unsaturated group will be described. Specific examples of the unsaturated monocarboxylic acid used in the reaction (2) include acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, sorbic acid, α-cyanocinnamic acid, β-styrylacrylic acid and the like. Further, a half ester of a dibasic acid anhydride and a (meth) acrylate having a hydroxyl group may be used. Specifically, anhydrides such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, and succinic acid; and hydroxyl-containing (meth) such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate Half esters with acrylates and the like can be mentioned. These unsaturated monocarboxylic acids may be used alone or in combination of two or more.
Specific examples of the unsaturated monocarboxylic acid ester include the above-mentioned alkyl esters of the unsaturated monocarboxylic acid, and examples of the unsaturated monocarboxylic acid chloride include acrylic acid chloride and methacrylic acid chloride.
The ratio of the oxetane-modified compound (A) and the ethylenically unsaturated compound (d) in the reaction (2) (the charge ratio in the reaction mixture) is determined by the reactive functional group of the oxetane-modified compound (A) / the compound (d). The equivalent ratio of (carboxylic acid or the like) is preferably 0.1 or more, more preferably 0.3 to 1.0. If the equivalent ratio is less than 0.1, the introduction of the polymerizable group into the product becomes insufficient, so that sufficient photocurability cannot be obtained, and thus sufficient coating properties cannot be obtained. . On the other hand, if the equivalent ratio exceeds 1.0, unreacted ethylenically unsaturated compounds (such as unsaturated monocarboxylic acids) remain, which is not preferable. When the unreacted ethylenically unsaturated compound (d) remains, it may be removed by a known method such as distillation under reduced pressure and washing with an alkali.
The reaction (2) proceeds easily in the presence of a basic catalyst. As the basic catalyst, any of inorganic and organic bases such as sodium hydroxide, potassium hydroxide, pyridine and triethylamine can be used. The reaction temperature may be any temperature as long as it does not exceed the boiling point of the reaction solvent used, but is preferably in the range of about 0 ° C to 100 ° C in consideration of economy. More preferably, the temperature is from 20C to 70C.
The amount of the basic catalyst used is preferably 0.1 to 25 mol%, more preferably 0.5 to 20 mol%, per 1 mol of the oxetane-modified compound (A). , More preferably a ratio of 1 to 15 mol%. When the use amount of the basic catalyst is less than 0.1 mol%, the reaction may hardly proceed at a practical rate depending on the reaction. Since no remarkable reaction accelerating effect is observed, it is not preferable in terms of economy.
Next, the reaction with a polybasic acid anhydride will be described. In the present invention, 0.1 to 1.0 mol of the polybasic anhydride (e) is reacted with 1 chemical equivalent of the primary hydroxyl group in the photocurable compound (A ′) generated as described above. Thereby, an alkali-soluble photocurable compound (photocurable resin) (A ″) is produced. Among the photocurable compounds (A ′), ethylenically unsaturated compounds such as unsaturated monocarboxylic acids ( A primary hydroxyl group not subjected to the addition reaction with d) remains, and the addition reaction between the hydroxyl group and the polybasic acid anhydride introduces a carboxyl group, so that the compound becomes alkali-soluble.
Specific examples of the polybasic acid anhydride (e) include phthalic anhydride, succinic anhydride, octenyl phthalic anhydride, pentadodecenyl succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride Acids, 3,6-endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride, dibasic anhydrides such as trimellitic acid, or biphenyltetracarboxylic dianhydride, naphthalenetetracarboxylic acid Examples include tetrabasic dianhydrides such as dianhydride, diphenyl ether tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, pyromellitic anhydride, and benzophenone tetracarboxylic dianhydride. These can be used alone or as a mixture of two or more.
The reaction between the polybasic acid anhydride (e) and the photocurable compound (A ′) can be carried out at a temperature in the range of about 50 to 150 ° C., preferably 80 to 130 ° C. in the above-mentioned mixing ratio. is there. The amount of the polybasic acid anhydride to be used is preferably 0.1 to 1.0 mol per 1 chemical equivalent of primary hydroxyl group in the photocurable compound (A '). If the amount of the polybasic acid anhydride is less than 0.1 mol, the amount of carboxyl groups to be introduced becomes small, and the resulting resin is not provided with sufficient alkali solubility, which is not preferable. On the other hand, when used in a large amount exceeding 1.0, unreacted polybasic acid anhydride remains in the resin and deteriorates properties such as durability and electric properties, which is not preferable.
In the reaction between the polybasic acid anhydride (e) and the photocurable compound (A ′), the above-mentioned tertiary amine, quaternary onium salt, tertiary phosphine, phosphonium ylide, crown ether complex is used as a reaction accelerator. Adducts of tertiary amines or tertiary phosphines with carboxylic acids or strongly acidic phenols can be used. The amount used is preferably in the range of 0.1 to 25 mol%, more preferably 0.5 to 20 mol%, more preferably 1 to 15 mol%, based on the polybasic acid anhydride (e). is there. However, when the reaction accelerator used in the reaction with the ethylenically unsaturated compound (d) such as the above-mentioned unsaturated monocarboxylic acid remains in the system, the reaction accelerator is not newly added. Can also promote the reaction.
The reaction between the oxetane-modified compound (A) and the ethylenically unsaturated compound (d) and the reaction between the photocurable compound (A ′) and the polybasic anhydride (e) are carried out in the presence of an organic solvent or without solvent. Although the process proceeds in any of the following, it is also possible to perform the reaction in the presence of a diluent described below to improve the stirring effect during the reaction. When an organic solvent is used as a diluent during synthesis, the solvent may be removed by a known method such as distillation under reduced pressure.
Known organic solvents can be used as long as they do not adversely affect the reaction and can maintain the reaction temperature. Specifically, alcohols such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl Glycol esters such as ether acetate and dipropylene glycol monomethyl ether acetate; ethers such as diethylene glycol dimethyl ether and dipropylene glycol dimethyl ether; ketones such as methyl isobutyl ketone and cyclohexanone; and hydrocarbons such as toluene (xylene).
In the reaction between the oxetane-modified compound (A) and the ethylenically unsaturated compound (d) and the reaction between the photocurable compound (A ′) and the polybasic acid anhydride (e), an unsaturated double bond For the purpose of preventing gelation due to polymerization, air may be blown or a polymerization inhibitor may be added. Examples of the polymerization inhibitor include hydroquinone, tolquinone, methoxyphenol, phenothiazine, triphenylantimony, copper chloride and the like.
The photocurable compound (A ′) and the alkali-soluble photocurable compound (A ″) obtained by the method of the present invention are compounds that generate radicals upon irradiation with active energy rays, ie, a photopolymerization initiator (B). And mixing a diluent (C) as required to form a photocurable composition, and further mixing a thermosetting compound (D) having at least two oxirane groups or oxetanyl groups in the molecule. It becomes a photo-curable and thermo-curable composition, and by heating the coating film after exposure and development, it does not cause curing shrinkage, and has excellent heat resistance, adhesion, electrical insulation, chemical resistance, etc. Particularly, when the photocurable / thermosetting composition of the present invention contains an alkali-soluble photocurable compound (A ″), development with an aqueous alkali solution is possible. A.
Specific examples of the photopolymerization initiator (B) include benzoin such as benzoin, benzoin methyl ether and benzoin ethyl ether and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 4- (1-t Acetophenones such as -butyldioxy-1-methylethyl) acetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone; 2,4-dimethylthioxanthone; -Thioxanthones such as -diisopropylthioxanthone and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone, 4- (1-t-butyldioxy-1-methylethyl) Benzophenones such as benzophenone and 3,3 ', 4,4'-tetrakis (t-butyldioxycarbonyl) benzophenone; 2-methylthio-1- [4- (methylthio) phenyl] -2-morpholino-propane-1- Aminoacetophenones such as on and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one; alkylphosphines such as 2,4,6-trimethylbenzoylphosphine oxide; 9-phenyl And acridines such as acridine.
These photopolymerization initiators can be used alone or as a mixture of two or more, and the compounding amount is 0.1 to 100 parts by mass of the photocurable compound (A ′ or A ″). When the amount is less than 0.1 part by mass, 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 it is added in a large amount exceeding 30 parts by mass, there is no change in photocurability, which is economically undesirable.
In the photocurable composition or the photocurable / thermocurable composition of the present invention, a sensitizer may be used in combination with the photopolymerization initiator in order to promote curing by active energy rays. Examples of sensitizers that can be used in combination include triethylamine, triethanolamine, 2-dimethylaminoethanol, ethyl N, N-dimethylaminobenzoate, isoamyl N, N-dimethylaminobenzoate, and pentyl-4-dimethylaminobenzoate. Thioethers such as β-thiodiglycol; sensitizing dyes such as (keto) coumarin and thioxanthene; and alkylborates of dyes such as cyanine, rhodamine, safranin, malachite green, and methylene blue. Is mentioned. These sensitizers may be used alone or in combination of two or more. The use amount thereof is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the photocurable compound (A 'or A ").
Further, the photocurable composition or the photocurable / thermocurable composition of the present invention contains a diluent. As the diluent (C), in addition to the above-described organic solvent, a compound having a polymerizable group capable of participating in a curing reaction, for example, a known reactive compound such as a monofunctional acrylate and / or a polyfunctional acrylate. Diluents can be used, which can improve photocurability as well as adjusting the viscosity of the composition. Specific examples of the reactive diluent include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isodecyl (meth) acrylate. , Lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) ) Acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, dimethylaminoethyl (meth) A) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate Glycerin di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, polyester acrylate, and dibasic acid anhydride and at least one in one molecule Reaction products with the above-mentioned alcohol having an unsaturated group can be exemplified. The diluent (C) is used alone or as a mixture of two or more, and the amount of the diluent is not particularly limited. In addition, in this specification, (meth) acrylate is a general term for acrylate, methacrylate, and a mixture thereof (the same applies to other similar expressions).
The thermosetting compound (D) having at least two oxirane groups or oxetanyl groups in one molecule is a polyfunctional epoxy compound (D-1) or an oxetane compound (D-2).
Examples of the polyfunctional epoxy compound (D-1) include novolak type epoxy resins (for example, novolaks obtained by reacting phenols such as phenol, cresol, halogenated phenol, and alkylphenol with formaldehyde under an acid catalyst; It is obtained by reacting epichlorohydrin and / or methyl epichlorohydrin, and as commercial products, EOCN-103, EOCN-104S, EOCN-1020, EOCN-1027, EPPN-201, BREN- manufactured by Nippon Kayaku Co., Ltd. S: DEN-431, DEN-439 manufactured by Dow Chemical Company; N-730, N-770, N-865, N-665, N-673, N-695, manufactured by Dainippon Ink and Chemicals, Inc. VH-4150 etc.), bisphenol A type epoxy resin (for example, Bisphenols such as bisphenol A, bisphenol F, bisphenol S, tetrabromobisphenol A, and the like, obtained by reacting epichlorohydrin and / or methyl epichlorohydrin, and glycidyl ether of bisphenol A and a condensate of the bisphenols with epichlorohydrin and / or Methyl epichlorohydrin is obtained by reaction, and commercially available products include, for example, Epicoat 1004 and Epicoat 1002 manufactured by Yuka Shell Epoxy Co., Ltd .; DER-330 and DER-337 manufactured by Dow Chemical Company), Tris Phenolmethane type epoxy resin (for example, obtained by reacting epichlorohydrin and / or methyl epichlorohydrin with trisphenolmethane, triscresol methane, etc., and commercially available Examples thereof include EPPN-501 and EPPN-502 manufactured by Nippon Kayaku Co., Ltd.), tris (2,3-epoxypropyl) isocyanurate, biphenyl glycidyl ether, other alicyclic epoxy resins, amino group-containing epoxy resins, Known and commonly used epoxy resins such as a polymerization type epoxy resin, a cardo type epoxy resin, and a calixarene type epoxy resin can be used alone or in combination of two or more.
Representative examples of the compound having two oxetane rings in the molecule include bisoxetanes represented by the following general formula (4).

In the above general formula (4), R¹Has the same meaning as described above, and R⁵Are linear or branched saturated hydrocarbons having 1 to 12 carbon atoms, linear or branched unsaturated hydrocarbons having 1 to 12 carbon atoms, the following formulas (A), (B), (C), ( Aromatic hydrocarbons represented by D) and (E), linear or cyclic alkylenes containing a carbonyl group represented by formulas (F) and (G), represented by formulas (H) and (I) It is a group having two valences selected from aromatic hydrocarbons containing a carbonyl group.

Where R⁶Represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group, or an aralkyl group;⁷Is -O-, -S-, -CH₂-, -NH-, -SO₂-, -CH (CH₃)-, -C (CH₃)₂-Or -C (CF₃)₂-, R⁸Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

In the formula, n represents an integer of 1 to 12.

Representative examples of compounds having three or more oxetane rings in the molecule include compounds represented by the following general formula (5), oxetane and novolak resin, poly (p-hydroxystyrene), cardo-type oxetane resin , Calixarenes, calixresorcinarenes, and etherified products with a resin having a hydroxyl group such as silicone resins such as silsesquioxane. Other examples include a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate.

In the above general formula (5), R¹Has the same meaning as described above, and R⁹Is a hydroxyl group-containing resin residue of the etherified product, a branched alkylene group having 1 to 12 carbon atoms as shown by the following formulas (J), (K) and (L), formulas (M), (N) and The aromatic hydrocarbons represented by (P). M is the residue R⁹And represents an integer of 3 or more, preferably an integer of 3 to 5000.

Where R¹⁰Represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group.
The oxetane compound (D-2) as described above can be used alone or in combination of two or more.
The compounding amount of the thermosetting compound (epoxy compound or oxetane compound) (D) is appropriately 5 to 100 parts by mass with respect to 100 parts by mass of the photocurable compound (A ′ or A ″). Preferably it is 15 to 60 parts by mass.
Further, from the viewpoint of resolution, a finely divided epoxy compound or oxetane compound that is hardly soluble in the diluent (C) or a combination of a hardly soluble epoxy compound or oxetane compound and a soluble epoxy compound or oxetane compound is used. Is preferred.
Furthermore, in order to accelerate the thermosetting reaction, a known curing accelerator such as a tertiary amine, a quaternary onium salt, a tertiary phosphine, a crown ether complex, or an imidazole derivative, dicyandiamide can be used in a small amount. . The curing accelerator (E) can be arbitrarily selected from these, and these may be used alone or in combination of two or more. In addition, known curing accelerators such as phosphonium ylide can be used.
Examples of the imidazole derivative include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2- (Cyanoethyl) -2-ethyl-4-methylimidazole and the like. Specific examples of commercially available products include 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, and 2P4MHZ manufactured by Shikoku Chemicals Co., Ltd. As a measure for improving the stability over time, Asahi Chiba Corporation's NOVACURE HX-3721, HX-3748, HX-3741, HX-3088, HX-3722, HX-3742, HX-3921HP, HX-3941HP, HX-3613 and the like are also included.
The amount of the curing accelerator (E) to be used is in the range of 0.1 to 25 mol%, preferably 0.5 to 20 mol%, more preferably 1 to 25 mol% based on 1 mol of the oxirane group or oxetanyl group. 15 mol%. If the amount of the curing accelerator used is less than 0.1 mol% with respect to the oxirane group / oxetanyl group, the curing reaction hardly proceeds at a practical rate. Since no remarkable reaction accelerating effect is observed, it is not preferable in terms of economy.
By the way, since a polyfunctional oxetane compound has a slower reactivity and is more stable than a polyfunctional epoxy compound, a photo-curable / thermo-curable composition containing the compound has a long shelf life and a one-pack It becomes possible to compose the mold. However, when relatively long time is required from the composition preparation to the start of use, when the thermosetting component as described above is previously mixed with the photo-curable / thermo-curable composition, the circuit board blank is used. It is desirable to mix both at the time of use, since the viscosity tends to increase before coating. That is, a curing agent solution mainly composed of the polyfunctional epoxy compound (D-1) or the polyfunctional oxetane compound (D-2) and the photocurable compound (A ′ or A ″) mainly, It is preferable to form a two-part composition of a base solution containing a curing accelerator (E), etc., and to mix and use them when using the photopolymerizable monomer, filler, coloring pigment, etc. It can also be mixed with an organic solvent solution of a curable compound (polyfunctional epoxy compound or polyfunctional oxetane compound).
Furthermore, the photocurable composition or the photocurable / thermocurable composition of the present invention has an adhesive property of a cured product, hardness, for the purpose of raising properties such as solder heat resistance, within a range that does not impair photoreactivity. If necessary, known and conventional fillers such as barium sulfate, silicon oxide, silica, talc, clay and calcium carbonate, phthalocyanine green, phthalocyanine blue, titanium oxide, known and commonly used coloring pigments such as carbon black, defoamers, Various additives such as an adhesion imparting agent and a leveling agent may be added.
The curable composition prepared by mixing the above components is applied on a substrate by an appropriate method, and cured by irradiation with active energy rays.
For example, in the case of forming a resist pattern, a diluent (C) as described above is added to the obtained photocurable / thermosetting composition to adjust the viscosity to a desired value, and then a circuit is formed. It is applied to a substrate such as a printed wiring board by an appropriate coating method such as a screech printing method, a curtain coating method, a roll coating method, a dip coating method, a spin coating method, and temporarily dried at a temperature of, for example, about 60 to 120 ° C. By doing so, the organic solvent contained in the composition is removed, and a tack-free coating film is formed. Thereafter, the resist pattern can be formed by selectively exposing with an active energy ray through a photomask on which a predetermined exposure pattern is formed, and developing an unexposed portion with a dilute alkaline aqueous solution. Furthermore, a cured coating film having excellent properties such as adhesion, solder heat resistance, chemical resistance, electric insulation, and electric corrosion resistance is formed by heating and thermosetting at a temperature of, for example, about 140 to 200 ° C. it can. Further, by performing post-UV curing before or after thermal curing, various properties can be further improved.
As the aqueous alkali solution used for the development, an aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, ammonia, an organic amine, tetramethylammonium hydroxide, or the like can be used. The concentration of the alkali in the developer may be approximately 0.1 to 5.0 wt%. As the development method, a known method such as dip development, paddle development, and spray development can be used.
Examples of the irradiation light source for photocuring the photocurable composition or the photocurable / thermocurable composition of the present invention include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, and a metal halide lamp. Appropriate. Further, a laser beam or the like can also be used as an active light beam for exposure. In addition, electron beams, α-rays, β-rays, γ-rays, X-rays, neutron rays, etc. can be used.
Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the following, “parts” and “%” are all based on mass unless otherwise specified.
Example 1 (Synthesis of oxetane-modified compound)
10.8 g of p-cresol, 2.6 g of 18-crown-6-ether and 1.2 g of potassium-tert-butoxide were dissolved in 30 ml of N-methylpyrrolidone and stirred at room temperature until uniform. Thereafter, 34.8 g of 3-ethyl-3-hydroxymethyloxetane (manufactured by Toagosei Co., Ltd.) was added, and the mixture was stirred at 160 ° C. for 12 hours. After completion of the reaction, the reaction mother liquor was subjected to silica gel chromatography (developing solvent; ethyl acetate: chloroform = 1: 1), and then isolated and purified by preparative liquid chromatography to obtain a pale yellow viscous liquid as oxetane-modified compound A-1. Was obtained 19.8 g. The yield was 88%. The structure is confirmed by IR spectrum and¹The structure was determined by 1 H-NMR to confirm that the structure was represented by the following chemical formula (6). FIG. 1 shows the IR spectrum of the obtained oxetane-modified compound A-1.

Example 2 (Synthesis of photocurable compound)
5.6 g of the oxetane-modified compound A-1 obtained in Example 1, 1.0 g of sodium hydroxide, and a small amount of a polymerization inhibitor were mixed with 50.0 g of methyl methacrylate, and the mixture was stirred at room temperature for 4 hours. After stirring, methyl methacrylate and methanol were distilled off under reduced pressure, and the residue was dissolved in chloroform and washed three times with water. After the organic layer was dried over anhydrous magnesium sulfate, chloroform was distilled off under reduced pressure to obtain 10.0 g of a yellow viscous liquid as photocurable compound A'-1. The structure is confirmed by IR spectrum and¹H-NMR was used. FIG. 2 shows the IR spectrum of the obtained photocurable compound A′-1. Also,¹The esterification rate calculated from 1 H-NMR was 68.3%.
Example 3
Using the photocurable compound A'-1 obtained in Example 2, a photocurable composition having the following composition was prepared.
Photocurable compound A'-1 @ 25 parts
Irgacure 184 5 copies
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Total 30 copies
When the obtained photocurable composition was applied on a copper plate and irradiated with ultraviolet rays for 120 seconds by an ultraviolet irradiation device (UIS-2510AA manufactured by Ushio Inc.), it became tack-free and a film insoluble in acetone was formed. Was.
Example 4 (Synthesis of oxetane-modified resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 60.0 g of polyparahydroxystyrene (manufactured by Maruzen Petrochemical Co., Ltd., trade name: Marcalinker) and 3-ethyl-3-hydroxymethyloxetane 174. 4 g, 5.6 g of potassium t-butoxy, 13.7 g of 18-crown-6-ether and 300 ml of N-methylpyrrolidone were added, and the mixture was reacted at 140 ° C. for 6 hours. The reaction mixture was poured into a large amount of water to precipitate the product. The resulting precipitate was collected by filtration, further dissolved in a small amount of tetrahydrofuran, poured into a large amount of water, and purified by reprecipitation. The obtained precipitate was dried under reduced pressure to obtain 107 g of an oxetane-modified resin A-2 having a repeating unit represented by the following chemical formula (7). The yield was 91%. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. FIG. 3 shows the IR spectrum of the obtained oxetane-modified resin A-2.

Example 5 (Synthesis of photocurable resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 59.0 g of the oxetane-modified resin A-2 obtained in Example 4, 250.0 g of methyl methacrylate, 3.3 g of potassium hydroxide, and 300 ml of tetrahydrofuran was added and reacted at room temperature for 12 hours. The reaction mixture was dissolved in chloroform and washed with water three times. The organic layer was dried over magnesium sulfate and then reprecipitated and purified with n-hexane to obtain 59.6 g of a photocurable resin A′-2 into which an unsaturated double bond was introduced. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. FIG. 4 shows the IR spectrum of the obtained photocurable resin A′-2. Also,¹The esterification ratio was 35% from the integration ratio of H-NMR.
Example 6 (Synthesis of alkali-soluble photocurable resin)
In a 500 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 200 g of the photocurable resin A'-2 obtained in Example 5, 76 g of tetrahydrophthalic anhydride, 4 g of triphenylphosphine, and propylene glycol 183 g of monomethyl ether acetate was added and reacted at 80 ° C. for 3 hours to obtain a resin solution containing 60% of the photocurable resin A ″ -2 into which a carboxyl group was introduced. It disappeared and it was confirmed that broad absorption derived from the hydroxyl group of the carboxylic acid appeared, and the IR spectrum of the obtained photocurable resin A ″ -2 is shown in FIG. The acid value of the resin solid content was 100 mgKOH / g. This resin was soluble in a 1% aqueous sodium carbonate solution.
Example 7
Using the photocurable resin A'-2 obtained in Example 5, a photocurable composition having the following composition was prepared.
Photocurable resin A'-2 @ 30 parts
Irgacure 184 3 copies
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Hydroxyethyl methacrylate 30 parts
0.3 parts of silicone defoamer
63.3 copies in total
The obtained photocurable composition was applied on a copper foil to a film thickness of about 10 μm, and irradiated with ultraviolet light for 480 seconds by an ultraviolet irradiation device (UIS-2510AA, manufactured by Ushio Inc.). A strong film insoluble in acetone was formed.
Example 8
Using the photocurable resin A ″ -2 obtained in Example 6, a photocurable composition having the following composition was prepared.
Photocurable resin A "-2 @ 100 parts
Irgacure 907 $ 10
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Dipentaerythritol hexaacrylate 30 parts
Silicone antifoam agent 1 part
TEPIC (Nissan Chemical Industries, Ltd. epoxy resin) 30 parts
3-phenylimidazole 3 parts
Total 174 copies
The photocurable composition was applied on a copper foil to a thickness of about 25 μm, and was temporarily dried at 80 ° C. for 20 minutes. 500mJ / cm²After selectively irradiating with ultraviolet light, development was performed with a 1% aqueous solution of sodium carbonate for 120 seconds. As a result, an unexposed portion was dissolved and removed, and an image was formed. Furthermore, when the coated film after development was heated at 150 ° C. for 30 minutes, the thermosetting reaction proceeded, and a stronger film insoluble in organic solvents such as acetone and tetrahydrofuran could be formed.
Example 9 (Synthesis of oxetane-modified resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 60.0 g of cresol novolak resin, 61.0 g of 3-methyl-3-hydroxymethyloxetane, 5.6 g of potassium t-butoxy, and 18-crown-6. -13.7 g of ether and 300 ml of N-methylpyrrolidone were added, and the reaction was carried out at 160 ° C for 6 hours. The reaction mixture was poured into a large amount of water to precipitate the product. The resulting precipitate was collected by filtration, further dissolved in a small amount of tetrahydrofuran, poured into a large amount of water, and purified by reprecipitation. The obtained precipitate was dried under reduced pressure to obtain 107 g of the desired oxetane-modified resin A-3. The yield was 91%, and the oxetane addition rate was 100%. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. FIG. 6 shows the IR spectrum of the obtained oxetane-modified resin A-3.
Example 10 (Synthesis of photocurable resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 44.4 g of the oxetane-modified resin A-3 obtained in Example 9, 200.0 g of methyl methacrylate, 3.3 g of potassium hydroxide, and 300 ml of tetrahydrofuran was added and reacted at room temperature for 12 hours. The reaction mixture was dissolved in chloroform and washed with water three times. The organic layer was dried over magnesium sulfate and then reprecipitated and purified with n-hexane to obtain 48.0 g of a photocurable resin A′-3 into which an unsaturated double bond was introduced. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. FIG. 7 shows the IR spectrum of the obtained photocurable resin A′-3. Also,¹The esterification ratio was 35% from the integration ratio of H-NMR.
Example 11 (Synthesis of alkali-soluble photocurable resin)
In a 500 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 200 g of the photocurable resin A'-3 obtained in Example 10, 76 g of tetrahydrophthalic anhydride, 4 g of triphenylphosphine, and propylene glycol 183 g of monomethyl ether acetate was added, and the mixture was reacted at 80 ° C. for 3 hours to obtain a resin solution containing 60% of the photocurable resin A ″ -3 into which a carboxyl group had been introduced. It disappeared and it was confirmed that broad absorption derived from the hydroxyl group of the carboxylic acid appeared, and the IR spectrum of the obtained photocurable resin A ″ -3 is shown in FIG. The acid value of the resin solid content was 100 mgKOH / g. This resin was soluble in a 1% aqueous sodium carbonate solution.
Example 12
Using the photocurable resin A'-3 obtained in Example 10, a photocurable composition having the following composition was prepared.
Photocurable resin A'-3 @ 30 parts
Irgacure 184 3 copies
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Hydroxyethyl methacrylate 30 parts
0.3 parts of silicone defoamer
63.3 copies in total
The obtained photocurable composition was applied on a copper foil to a film thickness of about 10 μm, and irradiated with ultraviolet light for 480 seconds by an ultraviolet irradiation device (UIS-2510AA, manufactured by Ushio Inc.). A strong film insoluble in acetone was formed.
Example 13
Using the photocurable resin A ″ -3 obtained in Example 11, a photocurable composition having the following composition was prepared.
Photocurable resin A "-3 @ 100 parts
Irgacure 907 $ 10
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Dipentaerythritol hexaacrylate 30 parts
Silicone antifoam agent 1 part
TEPIC (Nissan Chemical Industries, Ltd. epoxy resin) 30 parts
3-phenylimidazole 3 parts
Total 174 copies
The photocurable composition was applied on a copper foil to a thickness of about 25 μm, and was temporarily dried at 80 ° C. for 20 minutes. 500mJ / cm²After selectively irradiating with ultraviolet light, development was performed with a 1% aqueous solution of sodium carbonate for 120 seconds. As a result, an unexposed portion was dissolved and removed, and an image was formed. Furthermore, when the coated film after development was heated at 150 ° C. for 30 minutes, the thermosetting reaction proceeded, and a stronger film insoluble in organic solvents such as acetone and tetrahydrofuran could be formed.
Example 14 (Synthesis of oxetane-modified resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 60.0 g of cresol novolak resin, 61.0 g of 3-methyl-3-hydroxymethyloxetane, 5.6 g of potassium t-butoxy, and N-methylpyrrolidone 300 ml was added and the reaction was carried out at 160 ° C. for 6 hours. The reaction mixture was poured into a large amount of water to precipitate the product. The resulting precipitate was collected by filtration, further dissolved in a small amount of tetrahydrofuran, poured into a large amount of water, and purified by reprecipitation. The obtained precipitate was dried under reduced pressure to obtain 82.0 g of the desired oxetane-modified resin A-4. The yield was 68%, and the oxetane addition rate was 47%. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR.
Example 15 (Synthesis of oxetane-modified resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 60.0 g of cresol novolak resin, 61.0 g of 3-methyl-3-hydroxymethyloxetane, 5.0 g of sodium hydroxide, and 150 ml of N-methylpyrrolidone Was added and the reaction was carried out at 160 ° C. for 6 hours. The reaction mixture was poured into a large amount of water, and the product was precipitated by performing acid precipitation. The resulting precipitate was collected by filtration, further dissolved in a small amount of tetrahydrofuran, poured into n-hexane, and purified by reprecipitation. The obtained precipitate was dried under reduced pressure to obtain 110 g of an oxetane-modified resin A-5 having a repeating unit represented by the following chemical formula (8). The yield was 91%, and the oxetane addition rate was 100%. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. FIG. 9 shows the IR spectrum of the obtained oxetane-modified resin A-5.

Example 16 (Synthesis of oxetane-modified resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 60.0 g of cresol novolak resin, 61.0 g of 3-methyl-3-hydroxymethyloxetane, 7.0 g of potassium hydroxide, and 150 ml of N-methylpyrrolidone Was added and the reaction was carried out at 160 ° C. for 6 hours. The reaction mixture was poured into a large amount of water, and the product was precipitated by performing acid precipitation. The resulting precipitate was collected by filtration, further dissolved in a small amount of tetrahydrofuran, poured into n-hexane, and purified by reprecipitation. The obtained precipitate was dried under reduced pressure to obtain the oxetane-modified resin A-5 represented by the chemical formula (8). The yield was 90%, and the oxetane addition rate was 100%. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR.
Example 17 (Synthesis of photocurable resin)
In a 1000 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 44.4 g of the oxetane-modified resin A-5 obtained in Example 15, 200.0 g of methyl methacrylate, 3.3 g of potassium hydroxide, and 300 ml of tetrahydrofuran was added and reacted at room temperature for 12 hours. The reaction mixture was dissolved in chloroform and washed with water three times. The organic layer was dried over magnesium sulfate and then reprecipitated and refined with n-hexane to obtain 48.0 g of a photocurable resin A′-5 into which an unsaturated double bond was introduced. Its structure has an IR spectrum and¹Confirmed by 1 H-NMR. Also,¹The esterification ratio was 35% from the integration ratio of H-NMR.
Example 18 (Synthesis of alkali-soluble photocurable resin)
In a 500 ml flask equipped with a reflux condenser, a thermometer, and a stirrer, 200 g of the photocurable resin A′-5 obtained in Example 17, 76 g of tetrahydrophthalic anhydride, 4 g of triphenylphosphine, and propylene glycol 183 g of monomethyl ether acetate was added, and the mixture was reacted at 80 ° C. for 3 hours to obtain a resin solution containing 60% of the photocurable resin A ″ -5 into which a carboxyl group was introduced. It was confirmed that a broad absorption derived from the hydroxyl group of the carboxylic acid appeared, and the acid value of the resin solid was 100 mgKOH / g, and the resin was soluble in a 1% aqueous solution of sodium carbonate. there were.
Example 19
Using the photocurable resin A'-5 obtained in Example 17, a photocurable composition having the following composition was prepared.
Photocurable resin A'-5 @ 30 parts
Irgacure 184 3 copies
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Hydroxyethyl methacrylate 30 parts
0.3 parts of silicone defoamer
63.3 copies in total
The obtained photocurable composition was applied on a copper foil to a film thickness of about 10 μm, and irradiated with ultraviolet light for 480 seconds by an ultraviolet irradiation device (UIS-2510AA, manufactured by Ushio Inc.). A strong film insoluble in acetone was formed.
Example 20
Using the photocurable resin A ″ -5 obtained in Example 18, a photocurable composition having the following composition was prepared.
Photocurable resin A "-5 @ 100 parts
Irgacure 907 $ 10
(Photopolymerization initiator manufactured by Ciba Specialty Chemicals)
Dipentaerythritol hexaacrylate 30 parts
Silicone antifoam agent 1 part
TEPIC (Nissan Chemical Industries, Ltd. epoxy resin) 30 parts
3-phenylimidazole 3 parts
Total 174 copies
The photocurable composition was applied on a copper foil to a thickness of about 25 μm, and was temporarily dried at 80 ° C. for 20 minutes. 500mJ / cm²After selectively irradiating with ultraviolet light, development was performed with a 1% aqueous solution of sodium carbonate for 120 seconds. As a result, an unexposed portion was dissolved and removed, and an image was formed. Furthermore, when the coated film after development was heated at 150 ° C. for 30 minutes, the thermosetting reaction proceeded, and a stronger film insoluble in organic solvents such as acetone and tetrahydrofuran could be formed.
Industrial applicability
As described above, since the oxetane-modified compound (A) obtained by the present invention has two primary hydroxyl groups in the molecule, it is necessary to react the ethylenically unsaturated compound (d), for example, an unsaturated monocarboxylic acid. The photocurable compound (A ′) can be easily obtained by the reaction, and the alkali-soluble photocurable compound can be obtained by reacting the obtained photocurable compound (A ′) with the polybasic acid anhydride (e). (A ″) can be easily obtained, and by using these as a photocurable component, a photocurable composition that cures quickly by irradiation with active energy rays for a short time without causing significant curing shrinkage can be obtained. In particular, in the photocurable compound (A ″), since the polybasic acid anhydride (d) is bonded to the primary hydroxyl group, the bonding site is hardly cleaved thermally, Has excellent stability, by using this for its as a photocurable component, heat resistance, thermal stability excellent alkali developing type photocurable and thermosetting composition can be prepared. In addition, since a cured product excellent in electrical insulation, heat resistance, adhesion, chemical resistance, etc. can be obtained without causing curing shrinkage due to thermal curing after exposure and development, solder used in the production of printed wiring boards It is useful in various technical fields such as manufacturing of resists, etching resists, interlayer insulating materials for build-up substrates, plating resists, photosensitive dry films, PDP phosphors, and the like.
[Brief description of the drawings]
FIG. 1 is an IR spectrum of the oxetane-modified compound A-1 obtained in Example 1.
FIG. 2 is an IR spectrum of the photocurable compound A′-1 obtained in Example 2.
FIG. 3 is an IR spectrum of the oxetane-modified resin A-2 obtained in Example 4.
FIG. 4 is an IR spectrum of the photocurable resin A′-2 obtained in Example 5.
FIG. 5 is an IR spectrum of the photocurable resin A ″ -2 obtained in Example 6.
FIG. 6 is an IR spectrum of the oxetane-modified resin A-3 obtained in Example 9.
FIG. 7 is an IR spectrum of the photocurable resin A′-3 obtained in Example 10.
FIG. 8 is an IR spectrum of the photocurable resin A ″ -3 obtained in Example 11.
FIG. 9 is an IR spectrum of the oxetane-modified resin A-5 obtained in Example 15.

Claims (19)

An oxetane-modified compound comprising a reaction product of a compound (a) having at least one phenolic hydroxyl group in the molecule and a compound (b) having one oxetane ring and one primary hydroxyl group in the molecule. Compound (a) having at least one phenolic hydroxyl group in the molecule is phenol, substituted phenol (substituent is a saturated or unsaturated hydrocarbon group, halogen atom or aryl group), bisphenol A, bisphenol F, bisphenol S, brominated bisphenol A, biphenol, bixylenol, catechol, resorcin, hydroquinone, 1,4-naphthalenediol, 1,5-naphthalenediol, phenol novolak, cresol novolak, brominated phenol novolak, poly (hydroxystyrene), calix Arenes, 2,4,4'-trihydroxybenzophenone, 4,4 ', 4 "-methylidene trisphenol, tri (p-hydroxyphenyl) methylmethane, tri (p-hydroxyphenyl) ethyl Tan, and oxetane-modified compound of claim 1 is at least one compound selected from the group consisting of silsesquioxane. The oxetane-modified compound according to claim 1, wherein the compound (b) having one oxetane ring and one primary hydroxyl group in the molecule is a compound represented by the following general formula.

In the formula, R ¹ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Compound (a) having at least one phenolic hydroxyl group in the molecule and compound (b) having one oxetane ring and one primary hydroxyl group in the molecule are obtained by converting an alkali metal salt of an alkoxide, an alkali metal salt of phenoxide, Oxetane characterized in that the reaction is carried out in the presence of at least one catalyst (c) selected from the group consisting of alkali metal salts of metal salts, crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides. A method for producing a modified compound. The ratio of the compound (b) having one oxetane ring and one primary hydroxyl group in the molecule to the compound (a) having at least one phenolic hydroxyl group in the molecule (b) / (a) (in the reaction mixture) 5. The method according to claim 4, wherein the ratio of the charged components is 1 to 3 (molar ratio). The method according to claim 4, wherein the catalyst (c) is used in a proportion of 1 to 30 mol% with respect to 1 mol of the compound (a) having at least one phenolic hydroxyl group in the molecule. A light comprising a reaction product of the oxetane-modified compound according to claim 1 and a compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group. Curable compound. The photocuring according to claim 6, wherein the compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group is a compound represented by the following general formula. Compounds.

In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ² , R ³ and R ⁴ each represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group, an aralkyl group, X represents a cyano group, a fluorine atom or a furyl group, X represents -OH, -OR, Cl, Br or I, and R represents an alkyl group having 1 to 12 carbon atoms. Compound (a) having at least one phenolic hydroxyl group in the molecule and compound (b) having one oxetane ring and one primary hydroxyl group in the molecule are obtained by converting an alkali metal salt of an alkoxide, an alkali metal salt of phenoxide, Oxetane-modified compound (A) by reacting in the presence of at least one catalyst (c) selected from the group consisting of alkali metal salts of alkali metal salts, crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides. A) reacting the obtained oxetane-modified compound (A) with a compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group. Obtaining a photocurable compound (A ′) in which an unsaturated bond has been introduced into the oxetane-modified compound (A). For producing a photocurable compound. The ratio of the oxetane-modified compound (A) and the compound (d) (the charge ratio in the reaction mixture) is such that the equivalent ratio of the reactive functional group of the oxetane-modified compound (A) / the compound (d) is 0.1 or more. The method according to claim 9, wherein An alkali-soluble photocurable compound comprising a reaction product of the photocurable compound according to claim 7 and a polybasic acid anhydride (e). The polybasic anhydride (e) is phthalic anhydride, succinic anhydride, octenyl phthalic anhydride, pentadodecenyl succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, 3 , 6-Endomethylenetetrahydrophthalic anhydride, methylendmethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride, trimellitic acid, biphenyltetracarboxylic dianhydride, naphthalenetetracarboxylic dianhydride, diphenylethertetracarboxylic dianhydride The photocurable compound according to claim 11, which is at least one compound selected from the group consisting of cyclopentanetetracarboxylic dianhydride, pyromellitic anhydride, and benzophenonetetracarboxylic dianhydride. A compound (a) having a phenolic hydroxyl group and a compound (b) having one oxetane ring and one primary hydroxyl group in a molecule are obtained by mixing an alkali metal salt of an alkoxide, an alkali metal salt of a phenoxide, an alkali metal salt of a carboxylate, Reacting in the presence of at least one catalyst (c) selected from the group consisting of crown ether complexes of these alkali metal salts, metal hydroxides and metal hydrides to obtain oxetane-modified compounds (A);
The resulting oxetane-modified compound (A) is reacted with a compound (d) having at least one ethylenically unsaturated bond in the molecule and having one functional group that reacts with a hydroxyl group, to thereby form a photocurable compound ( A ′) and a step of reacting the obtained photocurable compound (A ′) with a polybasic acid anhydride (e) to obtain an alkali-soluble photocurable compound (A ″). A method for producing an alkali-soluble photocurable compound, which is a feature of the present invention. An alkali-soluble photocurable compound is prepared by reacting 0.1 to 1.0 mol of a polybasic acid anhydride (e) with respect to 1 chemical equivalent of a primary hydroxyl group in the photocurable compound (A ′). 14. The method of claim 13, wherein (A ") is obtained. A photocurable composition comprising the photocurable compound according to claim 7 and a photopolymerization initiator. The photocurable composition according to claim 15, further comprising a diluent. 12. A photocurable and heat-curable composition comprising the photocurable compound according to claim 7 or 11, a photopolymerization initiator, and a thermosetting compound having at least two oxirane groups or oxetanyl groups in the molecule. Curable composition. The photocurable / thermosetting composition according to claim 17, further comprising a diluent. The photocurable / thermosetting composition according to claim 17, further comprising a curing accelerator.

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