JP3962271B2 - Flame retardant thermosetting resin composition - Google Patents

Description

【００５２】
式中、Ｒ、Ｒ’は、それぞれ独立して、アルキル基、置換アルキル基、アリール基、置換アリール基、アリル基、置換アリル基、水素原子、ハロゲン原子を表し、又は、Ｒ、Ｒ’からなる組み合わせのうち少なくとも１つは結合した炭化水素基、又は、上記炭化水素基の一部の炭素原子が窒素原子、硫黄原子、酸素原子又は珪素原子で置換された官能基を示す。
【００５３】
上記ヒンダードアミン系化合物としては特に限定されず、公知の各種ヒンダードアミン系化合物が挙げられる。これらのヒンダードアミン系化合物は、単独で用いられても良いし、２種類以上が併用されても良い。
上記ヒンダードアミン系化合物は、ラジカル捕捉剤として機能し、非燃焼時においては難燃熱硬化性樹脂組成物に優れた耐光性を付与するとともに、燃焼時においては燃焼過程で生成する活性なラジカルを捕捉し、安定化することができる。したがって、上記ヒンダードアミン系化合物としては、分解温度が高い等の高温安定性に優れるものを用いることが好ましい。このような高温安定性に優れるヒンダードアミン系化合物の具体例としては、例えば、下記一般式（３）で表されるＮ−アルコキシヒンダードアミンが挙げられる。
【００５４】
【化２】

【００５５】
式中、Ｒは、下記式（４）で表される構造を示す。
【００５６】
【化３】

【００５７】
上記ヒンダードアミン系化合物のうち市販されているものとしては、例えば、三共社製の商品名「Ｓａｎｏｌ」シリーズ、旭電化工業社製の商品名「アデカスタブ」シリーズ、住友化学工業社製の商品名「スミソープ」シリーズ、共同薬品社製の商品名「バイオソープ」シリーズ、ＣｉｂａＳｐｅｃｉａｌｉｔｉｅｓ社製の商品名「Ｃｈｉｍａｓｓｏｒｂ」シリーズや商品名「Ｔｉｎｕｖｉｎ」シリーズ、Ｇｏｏｄｒｉｃｈ社製の商品名「Ｇｏｏｄｒｉｔｅ」シリーズ、ＢＡＳＦ社製の商品名「ユビナール」シリーズ等が挙げられる。これらの市販のヒンダードアミン系化合物は、単独で用いられても良いし、２種類以上が併用されても良い。
【００５８】
本発明で用いられる層状珪酸塩は、上述のように化学処理によって、本発明で用いられる熱硬化性樹脂中への分散性を向上させることができる。
上記化学処理は、カチオン性界面活性剤やヒンダードアミン系化合物によるカチオン交換法（以下、化学修飾（１）法ともいう）に限定されるものではなく、例えば、以下に示す化学修飾（２）〜化学修飾（６）法の各種化学処理法によっても実施することができる。これらの化学修飾法は、単独で用いられても良いし、２種類以上が併用されても良い。なお、化学修飾（１）法を含め、以下に示す各種化学処理法によって熱可塑性樹脂中及び／又は熱硬化性樹脂中への分散性を向上させた層状珪酸塩を、以下、「有機化層状珪酸塩」ともいう。
【００５９】
化学修飾（２）法は、化学修飾（１）法で化学処理された有機化層状珪酸塩の結晶表面に存在する水酸基を、これと化学結合し得る官能基、又は、化学結合はしなくとも化学的親和性の大きい官能基を分子末端に１個以上有する化合物で化学処理する方法である。
【００６０】
化学修飾（３）法は、化学修飾（１）法で化学処理された有機化層状珪酸塩の結晶表面に存在する水酸基を、これと化学結合し得る官能基、又は、化学結合はしなくとも化学的親和性の大きい官能基及び反応性官能基を分子末端に１個以上有する化合物で化学処理する方法である。
【００６１】
化学修飾（４）法は、化学修飾（１）法で化学処理された有機化層状珪酸塩の結晶表面を、アニオン性界面活性を有する化合物で化学処理する方法である。
【００６２】
化学修飾（５）法は、化学修飾（４）法において、アニオン性界面活性を有する化合物の分子鎖中のアニオン部位以外に反応性官能基を１個以上有する化合物で化学処理する方法である。
【００６３】
化学修飾（６）法は、上記化学修飾（１）法〜化学修飾（５）法のいずれかの方法で化学処理された有機化層状珪酸塩に、更に、例えば、無水マレイン酸変性ポリフェニレンエーテル系樹脂のような層状珪酸塩と反応可能な官能基を有する樹脂を添加した組成物を用いる方法である。
【００６４】
上記化学修飾（２）法における、水酸基と化学結合し得る官能基、又は、化学結合はしなくとも化学的親和性の大きい官能基としては特に限定されず、例えば、アルコキシ基、グリシジル基、カルボキシル基（二塩基性酸無水物も包含する）、水酸基、イソシアネート基、アルデヒド基等の官能基や、水酸基との化学的親和性が高いその他の官能基等が挙げられる。また、上記水酸基と化学結合し得る官能基、又は、化学結合はしなくとも化学的親和性の大きい官能基を有する化合物としては、特に限定されるものではないが、例えば、上記に例示した官能基を有するシラン化合物、チタネート化合物、グリシジル化合物、カルボン酸類、アルコール類等が挙げられる。これらの化合物は、単独で用いられても良いし、２種類以上が併用されても良い。
【００６５】
上記シラン化合物としては特に限定されず、例えば、ビニルトリメトキシシラン、
ビニルトリエトキシシラン、ビニルトリス（β−メトキシエトキシ）シラン、γ−アミノプロピルトリメトキシシラン、γ−アミノプロピルメチルジメトキシシラン、γ−アミノプロピルジメチルメトキシシラン、γ−アミノプロピルトリエトキシシラン、γ−アミノプロピルメチルジエトキシシラン、γ−アミノプロピルジメチルエトキシシラン、メチルトリエトキシシラン、ジメチルジメトキシシラン、トリメチルメトキシシラン、ヘキシルトリメトキシシラン、ヘキシルトリエトキシシラン、Ｎ−β−（アミノエチル）γ−アミノプロピルトリメトキシシラン、Ｎ−β−（アミノエチル）γ−アミノプロピルトリエトキシシラン、Ｎ−β−（アミノエチル）γ−アミノプロピルメチルジメトキシシラン、オクタデシルトリメトキシシラン、オクタデシルトリエトキシシラン、γ−メタクリロキシプロピルメチルジメトキシシラン、γ−メタクリロキシプロピルメチルジエトキシシラン、γ−メタクリロキシプロピルトリメトキシシラン、γ−メタクリロキシプロピルトリエトキシシラン等が挙げられる。これらのシラン化合物は、単独で用いられても良いし、２種類以上が併用されても良い。
【００６６】
化学修飾（４）法及び化学修飾（５）法における、アニオン性界面活性を有する化合物、アニオン性界面活性を有し分子鎖中のアニオン部位以外に反応性官能基を１個以上有する化合物としては、イオン相互作用により層状珪酸塩を化学処理できるものであれば特に限定されず、例えば、ラウリル酸ナトリウム、ステアリン酸ナトリウム、オレイン酸ナトリウム、高級アルコール硫酸エステル塩、第２級高級アルコール硫酸エステル塩、不飽和アルコール硫酸エステル塩等が挙げられる。これらの化合物は、単独で用いられても良いし、２種類以上が併用されても良い。
【００６７】
上記層状珪酸塩は、本発明の難燃熱硬化性樹脂組成物中に、広角Ｘ線回折測定法により測定した（００１）面の平均層間距離が３ｎｍ以上であり、かつ、一部又は全部が５層以下に分散していることが好ましく、より好ましくは、上記平均層間距離が３ｎｍ以上、５ｎｍ以下であり、かつ、一部又は全部が５層以下に分散していることである。
なお、本明細書において層状珪酸塩の平均層間距離とは、層状珪酸塩の微細薄片状結晶を層とした場合の平均の層間距離を意味し、Ｘ線回折ピーク及び透過型電子顕微鏡撮影、即ち、広角Ｘ線回折測定法により算出することができる。
【００６８】
層状珪酸塩の平均層間距離が３ｎｍ以上であるということは、層状珪酸塩の層間が３ｎｍ以上に開裂していることを意味しており、また、層状珪酸塩の一部又は全部が５層以下に分散しているということは、層状珪酸塩の積層体の一部又は全部が分散していることを意味する。これらはいずれも層状珪酸塩の層間の相互作用が弱まっていることを意味する。
【００６９】
層状珪酸塩の平均層間距離が３ｎｍ以上であり、かつ、一部又は全部が５層以下に分散していると、層状珪酸塩を熱硬化性樹脂中に配合し分散させて得られる本発明の難燃熱硬化性樹脂組成物は、優れた難燃性、力学的物性、高温物性、耐熱性、寸法安定性等の諸性能を発現するものとなる。平均層間距離が３ｎｍ未満であると層状珪酸塩のナノメートルスケールでの分散による効果が充分に得られず、力学物性、難燃性の改善は通常の無機充填材を複合した場合と同じ範囲に留まる。平均層間距離のより好ましい下限は３ｎｍ、上限は５ｎｍである。平均層間距離が５ｎｍを超えると、層状珪酸塩の結晶薄片が層毎に分離し、層状珪酸塩の相互作用が無視できるほど弱まるので、燃焼時の被膜形成速度が遅くなり、難燃性の向上が充分に得られないことがある。
【００７０】
層状珪酸塩の一部又は全部が５層以下に分散しているということは、具体的には、層状珪酸塩の１０％以上が５層以下に分散している状態にあることが好ましいことを意味し、より好ましくは層状珪酸塩の２０％以上が５層以下に分散している状態である。なお、層状珪酸塩の分散状態は、透過型電子顕微鏡を用いて５万〜１０万倍で観察して、一定面積中において観察できる層状珪酸塩の積層集合体の全層数（Ｘ）のうち５層以下で分散している積層集合体の層数（Ｙ）を計測し下記式（５）により算出することができる。
５層以下に分散している層状珪酸塩の割合（％）＝（Ｙ／Ｘ）×１００ （５）
【００７１】
層状珪酸塩の積層数は、５層以下に分層していることが好ましく、そのことにより、上記効果を得ることができるが、より好ましくは３層以下に分層していることであり、特に好ましくは単層状に薄片化していることである。
【００７２】
本発明の樹脂組成物において、層状珪酸塩の平均層間距離が３ｎｍ以上であり、かつ、層状珪酸塩の一部又は全部が５層以下に分散している状態、即ち、熱硬化性樹脂中に層状珪酸塩が高分散している状態であれば、熱硬化性樹脂と層状珪酸塩との界面面積が増大し、層状珪酸塩の結晶薄片間の平均距離が小さくなる。
【００７３】
熱硬化性樹脂と層状珪酸塩との界面面積が増大すると、層状珪酸塩の表面における熱硬化性樹脂の拘束の度合いが高まり、弾性率等の力学的物性が向上する。また、層状珪酸塩の表面における熱硬化性樹脂の拘束の度合いが高まると、溶融粘度が高まり、成形性も向上する。更に、ポリマー中では無機物に比べてガス分子の方がはるかに拡散しやすいので、熱硬化性樹脂中をガス分子が拡散する際には、無機物を迂回しながら拡散するため、ガスバリア性の発現も可能となる。
【００７４】
さらに詳しくは、層状珪酸塩の表面における熱硬化性樹脂の拘束の度合いが高まると、常温から高温までの広い温度領域で力学物性が向上する。驚くべき事には、樹脂のガラス転移点、融点以上の高温領域でも力学物性を保持することができる。このことにより、高温時の線膨張率も低く抑えることができる。かかる理由は明らかではないが、ガラス転移点又は融点以上の領域においても、微分散状態の層状珪酸塩が一種の疑似架橋点として作用しているためにこれら物性が発現していると考えられる。
【００７５】
また、ガスバリア性に関しては、耐溶剤性、吸湿性、吸水性が向上するばかりか、ガス分子以外の物質のバリア性も発現する。例えば、本発明の難燃熱硬化性樹脂組成物の用途の一つである多層プリント配線板では、銅回路からの銅のマイグレーションが問題となることがあるが、これも抑制される。更に、これら材料では、材料に添加された微量添加物でも、表面にブリードアウトすることで、メッキ不良などの不具合を発生することがあるが、添加物のブリードアウトも起こりにくい。
【００７６】
一方、層状珪酸塩の結晶薄片間の平均距離が小さくなると、燃焼時において、層状珪酸塩の結晶薄片の移動による焼結体を形成し易くなる。即ち、上記平均層間距離が３ｎｍ以上となるように層状珪酸塩の結晶薄片が分散した樹脂組成物は、難燃被膜となり得る焼結体を形成し易くなる。この焼結体は、燃焼時の早い段階で形成されるので、外界からの酸素の供給を遮断するのみならず、燃焼により発生する可燃性ガスをも遮断することができ、樹脂組成物は優れた難燃性を発現する。
【００７７】
本発明の難燃熱硬化性樹脂組成物において、上記熱硬化性樹脂１００重量部に対する上記層状珪酸塩の配合量の下限は１重量部、上限は４０重量部である。１重量部未満であると、難燃被膜となり得る焼結体を形成し難くなって、難燃効果が小さいものとなり、４０重量部を超えると、得られる難燃熱硬化性樹脂組成物の密度（比重）が高くなったり、屈曲に対する柔軟性が欠如したりするため、実用性が失われる。好ましい下限は２重量部、上限は２０重量部である。
【００７８】
上記熱硬化性樹脂中に層状珪酸塩を分散させる手段としては特に限定されず、例えば、上記有機化層状珪酸塩を用いる方法、熱硬化性樹脂と層状珪酸塩とを常法によって混合した後に発泡させる方法、ブロック共重合体を分散剤として用いる方法等が挙げられる。これらの分散方法を用いることにより、層状珪酸塩を熱硬化性樹脂中により均一かつ微細に分散することができる。
【００７９】
上記非ハロゲン系難燃剤としては、熱硬化性樹脂に難燃性を付与することができるものであれば特に限定されず、例えば、水酸化マグネシウム、水酸化アルミニウム、ドーソナイト、アルミン酸化カルシウム、２水和石膏、水酸化カルシウム等の金属水酸化物等が挙げられる。なかでも、水酸化マグネシウムや水酸化アルミニウムが好適に用いられる。
上記金属水酸化物は、各種の表面処理剤により表面処理が施されているものであることが好ましい。上記表面処理剤としては特に限定されず、例えば、脂肪酸系表面処理剤、シランカップリング剤、チタネート系カップリング剤、ポリビニルアルコール系表面処理剤、エポキシ系表面処理剤等が挙げられる。なかでも、低吸水性の難燃熱可塑性樹脂組成物が得られることから、脂肪酸系表面処理剤、シランカップリング剤、チタネートカップリング剤、エポキシ系表面処理剤が好適に用いられる。なかでも脂肪酸系表面処理剤、エポキシ系表面処理剤がより好適に用いられる。これらの金属水酸化物は、単独で用いられても良いし、２種類以上が併用されても良い。２種類以上の金属水酸化物を併用する場合、各々の金属水酸化物が異なる温度で吸熱脱水反応（分解脱水反応）を開始するので、より高い難燃効果が得られる。
【００８０】
上記金属水酸化物は、燃焼時の高熱下で吸熱脱水反応を起こすことにより、吸熱し、かつ、水分子を放出することにより、燃焼場の温度を低下させ、消火する効果がある。本発明の難燃熱硬化性樹脂組成物においては、層状珪酸塩が配合されていることにより、上記金属水酸化物による難燃効果が増大される。これは、層状珪酸塩の燃焼時の被膜形成による難燃効果と、金属水酸化物の吸熱脱水反応による難燃効果とが協奏的に起こり、それぞれの効果が助長されることによると考えられる。
【００８１】
本発明の難燃熱硬化性樹脂組成物において、上記熱硬化性樹脂１００重量部に対する上記非ハロゲン系難燃剤の配合量の下限は５重量部、上限は１００重量部である。５重量部未満であると、充分な難燃効果を発揮し難く、１００重量部を超えると、難燃効果は発現するものの、密度（比重）の増大、柔軟性の欠如、吸水率の増大、誘電特性や絶縁性の低下等のデメリットが発生する。好ましい下限は２０重量部、上限は６０重量部である。この範囲内であると機械的強度や電気的特性等の材料物性に問題となる領域ではなく、難燃熱硬化性樹脂組成物を絶縁基板材料として好適に用いることができる。
【００８２】
本発明の難燃熱硬化性樹脂組成物は、更に、難燃助剤を含有することが好ましい。難燃助剤が配合されることにより、酸素指数の向上や最大発熱速度の大幅な低下をもたらすことができる。
上記難燃助剤としては、例えば、ヒンダードアミン系化合物、フッ素樹脂、シリコーンオイル、ハイドロタルサイト類化合物、金属酸化物、及び、シリコーン−アクリル複合ゴムからなる群より選択される少なくとも１種類の難燃助剤が好適に用いられる。これらの難燃助剤を用いることにより熱硬化性樹脂の分解を防ぎ、最大発熱速度を抑制することができる
【００８３】
上記ヒンダードアミン系化合物は、上述のように、上記一般式（２）で表される構造を有する化合物である。上記ヒンダードアミン系化合物は、ラジカル捕捉剤として機能し、非燃焼時においては難燃熱硬化性樹脂組成物に優れた耐光性を付与するとともに、燃焼時においては燃焼過程で生成する活性なラジカルを捕捉し、安定化することができる。したがって、上記ヒンダードアミン系化合物としては、分解温度が高いなど高温安定性に優れるものを用いることが好ましい。かかる高温安定性に優れるヒンダードアミン系化合物としては、例えば、上記一般式（３）で表されるＮ−アルコキシヒンダードアミンが挙げられる。
【００８４】
本発明の難燃熱硬化性樹脂組成物においては、上記層状珪酸塩が配合されていることにより、ヒンダードアミン系化合物による難燃効果が増大される。これは、層状珪酸塩の燃焼時の被膜形成による難燃効果と、ヒンダードアミン系化合物のラジカル安定化反応による難燃効果とが協奏的に起こり、それぞれの効果が助長されることによると考えられる。また、非ハロゲン系難燃剤として用いられる水酸化マグネシウム等の金属水酸化物と併用される場合も、金属水酸化物の吸熱脱水反応による難燃効果と、ヒンダードアミン系化合物のラジカル安定化反応による難燃効果との相乗的な効果が大きいので好ましい。
【００８５】
上記フッ素樹脂は、燃焼時において溶融した難燃熱硬化性樹脂組成物中でフッ素樹脂が溶融粘度を向上させることにより、溶融樹脂が落下（ドリップ）するのを効果的に抑制し、延焼防止効果を付与できる。更に、これにより燃焼時に層状珪酸塩による焼結被膜の形成が阻害されないので、難燃性が向上する。フッ素樹脂はフッ素置換量が多いほど、分子構造上剛直になることにより凝集し難くなる。また、フッ素樹脂は延伸により繊維状構造をとり、より剛直になることが知られている。
【００８６】
上記シリコーンオイルやシリコーン−アクリル複合ゴムは、活性基を有する高分子と燃焼時に反応してチャー化を促進したり、又は、ガラス状の無機化合物の被膜が形成される時には、保護材として強固なものとなり、熱硬化性樹脂の熱分解を抑制することができる。
【００８７】
本発明の難燃熱硬化性樹脂において、上記熱硬化性樹脂１００重量部に対する上記難燃助剤の配合量の好ましい下限は０．１重量部、上限は２０重量部である。０．１重量部未満であると、良好な難燃性を発現することが難しくなり、２０重量部を超えると、機械的強度が低下したり、屈曲に対する柔軟性が欠如したりする等のデメリットを生じることがある。より好ましい下限は０．５重量部、上限は１５重量部である。
【００８８】
なお、上記難燃助剤としてヒンダードアミン系化合物を用いる場合には、熱硬化性樹脂１００重量部に対するヒンダードアミン系化合物の配合量の好ましい下限は０．１重量部、上限は１０重量部である。０．１重量部未満であると、良好な難燃性を発現することが難しくなり、１０重量部を超えると、難燃効果が却って低下することがある。より好ましい下限は０．２重量部、上限は４重量部である。
【００８９】
本発明の難燃熱硬化性樹脂組成物には、更に、必要に応じて適宜添加剤が添加されても良い。上記添加剤としては特に限定されず、例えば、酸化防止剤、熱安定剤、光安定剤、紫外線吸収剤、耐候剤、滑剤等が挙げられる。これらの添加剤は、単独で用いられても良いし、２種類以上が併用されても良い。
【００９０】
本発明の難燃熱硬化性樹脂組成物を製造する方法としては特に限定されず、例えば、熱硬化性樹脂、層状珪酸塩、非ハロゲン系難燃剤、難燃助剤の各所定配合量を直接配合して混合する方法や、熱硬化性樹脂に所定配合量以上の層状珪酸塩及び難燃助剤を配合、混合してマスターバッチを調製した後、調製されたマスターバッチに、所定の配合量となるように熱硬化性樹脂と非ハロゲン系難燃剤とを加えて希釈する、いわゆるマスターバッチ法等が挙げられる。
【００９１】
上記難燃熱硬化性樹脂組成物を製造する際の混合方法としては特に限定されず、種々の方法を用いることができ、例えば、熱硬化性樹脂、層状珪酸塩、非ハロゲン系難燃剤及び難燃助剤を、押出機、二本ロール、バンバリーミキサー等で溶融混練する方法や、熱硬化性樹脂、層状珪酸塩、非ハロゲン系難燃剤及び難燃助剤をこれらが溶解又は分散する有機溶媒中で混合する方法等が挙げられる。
【００９２】
本発明の難燃熱硬化性樹脂組成物は、ＡＳＴＭ Ｅ １３５４に準拠して、５０ｋＷ／ｍ²の輻射加熱条件下で３０分間加熱し燃焼した時の最大発熱速度が３５０ｋＷ／ｍ²以下であることが好ましい。３５０ｋＷ／ｍ²を超えると、充分な
難燃性を発現できないことがある。より好ましくは３００ｋＷ／ｍ²以下である。上記最大発熱速度がこの条件を満たす難燃熱硬化性樹脂組成物は、多くの場合ＵＬ９４に規定されている燃焼試験法においてＶ−０の認定水準を満たすことができる。
【００９３】
本発明の難燃熱硬化性樹脂組成物は、ＡＳＴＭ Ｅ １３５４に準拠して、５０ｋＷ／ｍ²の輻射加熱条件下で３０分間加熱し燃焼することにより得られた燃焼残渣を０．１ｃｍ／秒で圧縮した時の降伏点応力が４．９ｋＰａ以上であることが好ましい。４．９ｋＰａ未満であると、僅かな衝撃により燃焼残渣が簡単に崩壊し、火災時に部品の破損等により高電圧部からの再発火等の危険性が生じることがある。
【００９４】
本発明の難燃熱硬化性樹脂組成物は、コンピューター等の電子機器に用いられる絶縁基板の材料に好適である。本発明の難燃熱硬化性樹脂組成物を絶縁基板材料に用いることにより、高い難燃性を有し、廃棄時に有害物質を排出せず環境に負荷をかけない絶縁基板材料を得ることができる。
【００９５】
【実施例】
以下に実施例を掲げて本発明を更に詳しく説明するが、本発明はこれら実施例のみに限定されるものではない。
【００９６】
（参考例１）
ビスフェノールＡ型エポキシ樹脂（ダウ・ケミカル日本社製、商品名「Ｄ．Ｅ．Ｒ．３３１Ｌ」）１００重量部、硬化剤としてジシアンジアミド２．５重量部及び２−エチル−４−メチルイミダゾール０．１重量部からなるエポキシ樹脂組成物９２．３重量部に対し、ジステアリルジメチル４級アンモニウム塩で有機化処理した膨潤性フッ素マイカ（コープケミカル社製、商品名「ソマシフＭＡＥ−１００」）７．７重量部及び脂肪酸表面処理された水酸化マグネシウム（協和化学工業社製、商品名「キスマ５Ｊ」）５０重量部を配合し、撹拌ライカイ機で１時間混練し、脱泡して、液状の難燃エポキシ樹脂組成物を作製した。
得られた難燃エポキシ樹脂組成物を１４０℃で１時間加熱した後、１７０℃で２時間加熱して硬化させ、板状物に成形して、評価用サンプルを作製した。
【００９７】
（実施例１）
ビスフェノールＡ型エポキシ樹脂「Ｄ．Ｅ．Ｒ．３３１Ｌ」５５重量部、ＢＴレジン（三菱瓦斯化学社製、商品名「ＢＴ２１００Ｂ」）１５重量部、ネオペンチルグリコールジグリシジルエーテル１５重量部、カップリング剤としてγ−グリシドキシプロピルトリメトキシシラン（日本ユニカー社製、商品名「Ａ−１８７」）２重量部及び硬化触媒としてアセチルアセトン鉄（日本化学産業社製）１．０重量部からなる熱硬化性樹脂組成物９２．３部に対し、ジステアリルジメチル４級アンモニウム塩で有機化処理した膨潤性フッ素マイカ「ソマシフＭＡＥ−１００」７．７重量部及び脂肪酸表面処理された水酸化マグネシウム「キスマ５Ｊ」５０重量部を配合し、撹拌ライカイ機で１時間混練し、脱泡して、液状の難燃熱硬化性樹脂組成物を作製した。
得られた難燃熱硬化性樹脂組成物を１１０℃で３時間加熱した後、１６０℃で３時間加熱して硬化させ、板状物に成形して、評価用サンプルを作製した。
【００９８】
（参考例２）
更に、難燃助剤としてヒンダードアミン系化合物（ＢＡＳＦ社製、商品名「ユビナール５０５０Ｈ」）３重量部を配合したこと以外は参考例１と同様にして、液状の難燃エポキシ樹脂組成物を製造し、これを用いて評価用サンプルを作製した。
【００９９】
（参考例３）
ビスフェノールＡ型エポキシ樹脂（ダウ・ケミカル日本社製、Ｄ．Ｅ．Ｒ．３３１Ｌ）４５重量部、固形エポキシ樹脂（東都化成社製、ＹＰ５５）４５重量部、ジシアンジアミド（アデカ社製、アデカハードナーＥＨ−３６３６）３．１５重量部、変性イミダゾール（アデカ社製、アデカハードナーＥＨ−３３６６）１．３５重量部からなるエポキシ樹脂組成物９４．５重量部、層状珪酸塩としてトリオクチルメチルアンモニウム塩で有機化処理が施された合成ヘクトライト（コープケミカル社製、ルーセンタイトＳＴＮ）１０重量部、難燃剤としてシランカップリング剤にて表面処理された水酸化マグネシウム（協和化学工業社製、キスマ５Ｐ）７０重量部及び有機溶剤としてＤＭＦ（和光純薬社製、特級）５００重量部をビーカーに加え、撹拌機にて１時間撹拌した後、脱泡し、樹脂／層状珪酸塩溶液を得た。次いで、得られた樹脂／層状珪酸塩溶液を鋳型に入れた状態又はポリエチレンテレフタレートのシート上に塗布した状態で溶媒を除去した後、１１０℃で３時間加熱し、更に１７０℃で３０分間加熱して硬化させ、板状物に成形して、評価用サンプルを作製した。
【０１００】
（比較例１）
ジステアリルジメチル４級アンモニウム塩で有機化処理した膨潤性フッ素マイカ「ソマシフＭＡＥ−１００」を配合しなかったこと以外は参考例１と同様にして、液状の難燃エポキシ樹脂組成物を製造し、これを用いて評価用サンプルを作製した。
【０１０１】
（比較例２）
ジステアリルジメチル４級アンモニウム塩で有機化処理した膨潤性フッ素マイカ「ソマシフＭＡＥ−１００」を配合しなかったこと以外は実施例１と同様にして、液状の難燃熱硬化性樹脂組成物を製造し、これを用いて評価用サンプルを作製した。
【０１０２】
（比較例３）
ジステアリルジメチル４級アンモニウム塩で有機化処理した膨潤性フッ素マイカ「ソマシフＭＡＥ−１００」を配合しなかったこと以外は参考例２と同様にして、液状の難燃エポキシ樹脂組成物を製造し、これを用いて評価用サンプルを作製した。
【０１０３】
実施例１、参考例１〜３及び比較例１〜３で得られた評価用サンプルについて、以下の方法により層状珪酸塩の平均層間距離、層状珪酸塩の層の剥離状態、酸素指数、最大発熱速度、燃焼残渣の降伏点応力、耐ドリップ性及び吸水率を評価した。
結果は表１に示した。
【０１０４】
（層状珪酸塩の平均層間距離の測定）
Ｘ線回折測定装置（リガク社製、商品名「ＲＩＮＴ１１００」）を用いて、評価用サンプル中の層状珪酸塩の積層面の回折より得られる回折ピークの２θを測定し、下記のブラッグの回折式により、層状珪酸塩の（００１）面間隔（ｄ）を算出し、得られたｄを平均層間距離（ｎｍ）とした。
λ＝２ｄｓｉｎθ
式中、ｄは層状珪酸塩の面間隔を表し、θは回折角を表し、λは１．５４とした。
【０１０５】
（層状珪酸塩の層の剥離状態の評価）
透過型電子顕微鏡（日本電子社製、商品名「ＪＥＭ−１２００ＥＸＩＩ」）を用いて写真を撮影し、評価用サンプル中の層状珪酸塩の層の剥離状態を観察し、下記の基準により層状珪酸塩の層の剥離状態を評価した。
◎‥‥層状珪酸塩の数の２０％以上が５層以下で存在していた。
○‥‥５層以下で存在しているものを含んで分散していた。
×‥‥全てが５層を超える状態で存在していた。
【０１０６】
（酸素指数の測定）
燃焼試験ＡＳＴＭ Ｄ ２８６３「酸素指数によるプラスチックの燃焼性標準試験方法」に準拠して、評価用サンプルからなる試験片（長さ７０ｍｍ×幅６ｍｍ×厚さ３ｍｍ）を自立させて燃焼試験を行った。試験片が燃焼を継続するのに必要な酸素と窒素との混合気体中の容量％で表される最低酸素濃度の数値を酸素指数と呼び、所定の酸素濃度で試験片を燃焼させた時に、３分間以上燃焼し続けたか、又は、３分間以内に５０ｍｍ以上燃焼した場合を燃焼を継続できると判断し、その時の酸素濃度を試験片の酸素指数とした。
【０１０７】
（最大発熱速度及び燃焼残渣の降伏点応力の測定）
燃焼試験ＡＳＴＭ Ｅ １３５４「建築材料の燃焼性試験方法」に準拠して、評価用サンプルからなる試験片（１００ｍｍ×１００ｍｍ×厚さ３ｍｍ）にコーンカロリーメーターによって５０ｋＷ／ｍ²の熱線を照射して燃焼させた。この時、試験片の最大発熱速度（ｋＷ／ｍ²）を測定した。上記最大発熱速度が速いほど、初期着火時間が短く、着火し易いことになる。
また、ハンディー圧縮試験機（カトーテック社製、商品名「ＫＥＳ−Ｇ５」）を用いて、試験片の燃焼残渣を０．１ｃｍ／秒で圧縮し、燃焼残渣の降伏点応力（ｋＰａ）を測定した。
【０１０８】
（耐ドリップ性の評価）
評価用サンプルからなる試験片（長さ１２７ｍｍ×幅１２．７ｍｍ×厚さ０．８ｍｍ）の上部をクランプで固定し、試験片の下部底面に着火し、燃焼試験片が形状を維持できずに、その一部が脱落しないかを観察した。即ち、試験片の真下２０ｃｍの所に外科用綿を置き、試験中に燃焼試験片からの燃焼脱落物によって外科用綿が着火するか否かを目視で観察し、下記基準により耐ドリップ性を評価した。
○‥‥外科用綿が着火しなかった。
×‥‥外科用綿が着火した。
【０１０９】
（吸水率の測定）
評価用サンプルからなる試験片（長さ１０ｍｍ×幅１０ｍｍ×厚さ０．８ｍｍ）を沸騰水中に１時間浸漬し、試験前後の重量を量ることで、吸水率を測定した。
【０１１０】
【表１】

【０１１１】
【発明の効果】
本発明の難燃熱硬化性樹脂組成物は、上述の構成を有することにより、燃焼時に焼結体が形成され、燃焼残渣の形状が保持される。これにより燃焼後も形状崩壊が起こらず、延焼を防ぐことができる。また、強固な焼結体の生成により、難燃剤を大量に添加しなくとも難燃性を付与できるため、機械的強度、強靱性、誘電特性、絶縁性等の材料物性の低下が少ない。このような特性により火災の発生を防止でき、廃棄後の処理も安全かつ安価に実施することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention is a flame retardant thermosetting resin that exhibits excellent flame retardancy and is excellent in material properties such as mechanical strength, toughness, heat resistance, dielectric properties, insulation, light resistance, and environmental compatibility. Relates to the composition.
[0002]
[Prior art]
Electronic devices such as computers have parts that can be a source of ignition due to high voltage or high temperature, which can lead to a fire. Sex is required.
[0003]
On the other hand, polymer materials used for electronic devices such as computers have recently been required to be materials that do not burden the environment due to waste plastic disposal problems. It is desired.
[0004]
Currently, the flame retardant most frequently used as these insulating substrate materials is a halogen-based flame retardant (halogen-containing flame retardant) or a phosphorus-based flame retardant (phosphorus-containing flame retardant).
Since the halogen-based flame retardant has a high flame-retardant effect, it can exhibit flame retardancy only by adding a relatively small amount. Therefore, the moldability lowering action and the mechanical strength lowering action of the molded product are relatively small. However, when a halogen flame retardant is used, a large amount of halogen gas such as hydrogen halide or dioxin may be generated during molding or combustion. In view of safety, it is strongly desired to establish a so-called non-halogen flame retardant treatment method (treatment technology) that does not use a halogen-based flame retardant from the viewpoint of safety.
[0005]
On the other hand, an example in which a phosphorus flame retardant is added to a thermosetting resin instead of a halogen flame retardant has been reported. However, even when phosphorus-based flame retardants are used, toxic gases such as phosphine may be generated during combustion. Also, phosphorus-based flame retardants have low water resistance and may contaminate soil and water quality when discarded. Therefore, it is not preferable from the viewpoint of environmental protection. Moreover, regarding the flame retarding effect, the phosphorus-based flame retardant forms a film locally during combustion, but it is difficult to form a strong film as a continuous layer. Because the mechanical strength of the local coating is very weak, brittle ash is exposed at the time of combustion, and combustion residues fall off, so the function as a heat insulating layer is lost early, and the material is deformed. It may not be possible to stop the spread of fire.
[0006]
Therefore, in recent years, insulating substrate materials using non-halogen or non-phosphorous flame retardant resins have been developed in the field of electronic devices in order to switch to environment-friendly materials. One non-halogen or non-phosphorus flame retardant treatment method is to add a metal compound such as aluminum hydroxide, magnesium hydroxide or basic magnesium carbonate that does not generate toxic gas during combustion. When only the resin is added to the resin, the coating layer cannot be formed during combustion, the brittle ash is exposed, and the combustion residue drops off. However, the fire spread could not be stopped due to deformation. In addition, the flame retardant effect of metal hydroxides is low compared to halogen flame retardants and phosphorus flame retardants, so a large amount of addition is required, resulting in low mechanical strength of the material, which can withstand practical use. It may disappear. Furthermore, when a large amount of metal hydroxide is added, the dielectric properties and insulation properties particularly required for recent electronic materials may be impaired.
[0007]
In recent years, silicone flame retardants have attracted attention as flame retardants that do not contain halogen or phosphorus, can be blended into a wide range of plastics, and have high safety. Silicone flame retardants are known to exhibit flame retardancy by utilizing the oxygen barrier effect due to migration to the resin surface during combustion to form a non-combustible coating. However, when only a silicone-based flame retardant is added, the oxygen index is greatly improved, but a strong incombustible film cannot be formed as a continuous layer during actual combustion, and a flammable gas cannot be formed from the crack of the incombustible film. Spilled out, and there was a problem that fire spread could not be stopped.
[0008]
[Problems to be solved by the invention]
In light of the above-mentioned present situation, the present invention exhibits excellent flame retardancy, and is also excellent in mechanical properties, toughness, heat resistance, dielectric properties, insulating properties, light resistance, and other material properties and environmental compatibility. An object of the present invention is to provide a flame curable resin composition.
[0009]
[Means for Solving the Problems]
The present invention Resin comprising a mixture of epoxy resin and thermosetting polyimide resin It is a flame retardant thermosetting resin composition containing 100 parts by weight, 1 to 40 parts by weight of layered silicate, and 5 to 100 parts by weight of a non-halogen flame retardant.
The present invention is described in detail below.
[0010]
The flame retardant thermosetting resin composition of the present invention contains a thermosetting resin, a layered silicate, and a non-halogen flame retardant.
The thermosetting resin is a resin raw material consisting of a relatively low molecular weight material such as liquid, semi-solid, solid, etc. at room temperature, and exhibits fluidity at room temperature or under heating. It is a resin that undergoes a chemical reaction such as a curing reaction or a cross-linking reaction by its action, and forms a network-like three-dimensional structure with an increase in molecular weight and becomes insoluble and infusible.
[0011]
The thermosetting resin is not particularly limited. For example, an epoxy resin, a thermosetting polyimide resin, a phenol resin, an unsaturated polyester resin, a thermosetting polyphenylene ether resin, a polyfunctional maleimide resin, Examples include functional (meth) acrylate resins, polyalkenyl resins such as diallyl phthalate and trialkenyl isocyanurate, and dicyclopentadiene resins. But , Epoxy resin and Heat Curable polyimide resin For I can. These thermosetting resins may be used alone or in combination of two or more.
In the present specification, (meth) acrylate means acrylate or methacrylate.
[0012]
The epoxy resin is an organic compound having at least one oxirane ring. The number of epoxy groups in the epoxy resin is preferably 1 or more per molecule, and more preferably 2 or more per molecule. Here, the number of epoxy groups per molecule is obtained by dividing the total number of epoxy groups in the epoxy resin by the total number of molecules in the epoxy resin.
[0013]
It does not specifically limit as said epoxy resin, Various conventionally well-known epoxy resins can be used, For example, the epoxy resin (1)-epoxy resin (11) shown below etc. are mentioned. These epoxy resins may be used independently and 2 or more types may be used together.
[0014]
Examples of the epoxy resin (1) include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, and bisphenol S type epoxy resin; phenol novolac type epoxy resin, cresol novolac type epoxy Examples thereof include novolak-type epoxy resins such as resins; aromatic epoxy resins such as trisphenolmethane triglycidyl ether, and hydrogenated products and brominated products thereof.
[0015]
Examples of the epoxy resin (2) include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-2-methylcyclohexylmethyl 3,4-epoxy-2-methylcyclohexanecarboxylate. Bis (3,4-epoxycyclohexyl) adipate, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 2- (3,4-epoxycyclohexyl- Examples include alicyclic epoxy resins such as 5,5-spiro-3,4-epoxy) cyclohexanone-meta-dioxane and bis (2,3-epoxycyclopentyl) ether. As what is marketed among this epoxy resin (2), brand name "EHPE-3150" (softening temperature 71 degreeC, Daicel Chemical Industries Ltd. make) is mentioned, for example.
[0016]
Examples of the epoxy resin (3) include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, and polyethylene glycol diglycidyl ether. Polyglycidyl ether of a long-chain polyol containing glycidyl ether, diglycidyl ether of polypropylene glycol, polyoxyalkylene glycol or polytetramethylene ether glycol containing an alkylene group having 2 to 9 carbon atoms (preferably 2 to 4 carbon atoms) And aliphatic epoxy resins.
[0017]
Examples of the epoxy resin (4) include diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, diglycidyl-p-oxybenzoic acid, glycidyl ether-glycidyl ester of salicylic acid, and glycidyl dimer acid. Examples thereof include glycidyl ester type epoxy resins such as esters and hydrogenated products thereof.
[0018]
Examples of the epoxy resin (5) include triglycidyl isocyanurate, N, N′-diglycidyl derivative of cyclic alkylene urea, N, N, O-triglycidyl derivative of p-aminophenol, and N, N of m-aminophenol. , Glycidylamine type epoxy resins such as O-triglycidyl derivatives, and hydrogenated products thereof.
[0019]
Examples of the epoxy resin (6) include a copolymer of glycidyl (meth) acrylate and a radical polymerizable monomer such as ethylene, vinyl acetate, and (meth) acrylic acid ester.
[0020]
Examples of the epoxy resin (7) include those obtained by epoxidizing unsaturated carbon double bonds of a polymer mainly composed of a conjugated diene compound such as epoxidized polybutadiene or a polymer of partially hydrogenated product thereof. .
[0021]
Examples of the epoxy resin (8) include “polymer block mainly composed of vinyl aromatic compound” and “polymer block mainly composed of conjugated diene compound or partially hydrogenated product thereof such as epoxidized SBS”. Examples thereof include block copolymers having a “polymer block” in the same molecule, and epoxidized unsaturated carbon double bonds of a conjugated diene compound.
[0022]
Examples of the epoxy resin (9) include a polyester resin having one or more, preferably two or more epoxy groups per molecule.
[0023]
Examples of the epoxy resin (10) include urethane-modified epoxy resins and polycaprolactone-modified epoxy resins in which urethane bonds and polycaprolactone bonds are introduced into the structures of the various epoxy resins.
[0024]
Examples of the epoxy resin (11) include rubber-modified epoxy resins obtained by adding rubber components such as NBR, CTBN, polybutadiene, and acrylic rubber to the above various epoxy resins.
[0025]
It does not specifically limit as a hardening | curing agent used for the said epoxy resin, A conventionally well-known various hardening | curing agent for epoxy resins can be used, for example, compounds, such as an amine compound and the polyaminoamide compound synthesize | combined from an amine compound, 3 Examples include a class amine compound, an imidazole compound, a hydrazide compound, dicyanamide and derivatives thereof, a melamine compound, an acid anhydride, a phenol compound, a thermal latent cationic polymerization catalyst, and a photolatent cationic polymerization catalyst. These epoxy resin curing agents may be used alone or in combination of two or more.
[0026]
The amine compound is not particularly limited, and examples thereof include chain aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, polyoxypropylenediamine, polyoxypropylenetriamine, and derivatives thereof; Foronediamine, bis (4-amino-3-methylcyclohexyl) methane, diaminodicyclohexylmethane, bis (aminomethyl) cyclohexane, N-aminoethylpiperazine, 3,9-bis (3-aminopropyl) 2,4,8, Cycloaliphatic amines such as 10-tetraoxaspiro (5,5) undecane and derivatives thereof; m-xylenediamine, α- (m / p-aminophenyl) ethylamine, m-phenylenediamine, diaminodiphenylmethane, di Mino diphenyl sulfone, diaminodiphenyl diethyl dimethyl methane, alpha,. Alpha .'- bis (4-aminophenyl)-p-like aromatic amines and derivatives thereof diisopropylbenzene and the like. These amine compounds may be used alone or in combination of two or more.
[0027]
The compound synthesized from the above amine compound is not particularly limited. For example, the above various amine compounds and succinic acid, adipic acid, azelaic acid, sebacic acid, dodecadic acid, isophthalic acid, terephthalic acid, dihydroisophthalic acid, tetrahydro Polyaminoamide compounds and derivatives thereof synthesized from carboxylic acid compounds such as isophthalic acid and hexahydroisophthalic acid; polyaminoimide compounds and derivatives thereof synthesized from various amine compounds and maleimide compounds such as diaminodiphenylmethane bismaleimide; Ketimine compounds synthesized from the above various amine compounds and ketone compounds and their derivatives; various amine compounds and compounds such as epoxy compounds, urea, thiourea, aldehyde compounds, phenolic compounds, acrylic compounds, etc. Polyamino compounds and derivatives thereof is synthesized and the like. Compounds synthesized from these amine compounds may be used alone or in combination of two or more.
[0028]
The tertiary amine compound is not particularly limited. For example, N, N′-dimethylpiperazine, pyridine, picoline, benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) And tertiary amine compounds such as phenol and 1,8-diazabiscyclo (5,4,0) undecene-1 and derivatives thereof. These tertiary amine compounds may be used alone or in combination of two or more.
[0029]
The imidazole compound is not particularly limited, and examples thereof include imidazole compounds such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, and derivatives thereof. Is mentioned. These imidazole compounds may be used alone or in combination of two or more.
[0030]
The hydrazide compound is not particularly limited, and for example, 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, 7,11-octadecadien-1,18-dicarbohydrazide, eicosane diacid dihydrazide, And hydrazide compounds such as adipic acid dihydrazide and derivatives thereof. These hydrazide compounds may be used alone or in combination of two or more.
[0031]
The melamine compound is not particularly limited, and examples thereof include melamine compounds such as 2,4-diamino-6-vinyl-1,3,5-triazine and derivatives thereof. These melamine compounds may be used alone or in combination of two or more.
[0032]
The acid anhydride is not particularly limited. For example, phthalic acid anhydride, trimellitic acid anhydride, pyromellitic acid anhydride, benzophenone tetracarboxylic acid anhydride, ethylene glycol bisanhydro trimellitate, glycerol trisanhydro Trimellitate, methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, trialkyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, 5- (2, 5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trialkyltetrahydrophthalic anhydride-maleic anhydride adduct, dodecenyl succinic anhydride, polyazeline acid anhydride, polydodecane Dianhydride, Acid anhydrides such as Rorendo acid anhydride and derivatives thereof. These acid anhydrides may be used alone or in combination of two or more.
[0033]
The phenol compound is not particularly limited, and examples thereof include phenol compounds such as phenol novolak, o-cresol novolak, p-cresol novolak, t-butylphenol novolak, dicyclopentadiene cresol, and derivatives thereof. These phenol compounds may be used alone or in combination of two or more.
[0034]
The thermal latent cationic polymerization catalyst is not particularly limited. For example, benzylsulfonium salt, benzylammonium salt, benzylpyridinium salt, benzyl having antimony hexafluoride, phosphorous hexafluoride, boron tetrafluoride and the like as a counter anion. Examples include ionic thermal latent cationic polymerization catalysts such as phosphonium salts; nonionic thermal latent cationic polymerization catalysts such as N-benzylphthalimide and aromatic sulfonic acid esters. These thermal latent cationic polymerization catalysts may be used alone or in combination of two or more.
[0035]
The photolatent cationic polymerization catalyst is not particularly limited. For example, aromatic diazonium salts, aromatic halonium salts, aromatic sulfoniums having antimony hexafluoride, phosphorus hexafluoride, boron tetrafluoride and the like as counter anions. Ionic photolatent cationic polymerization catalysts such as onium salts such as salts, and organometallic complexes such as iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes; nitrobenzyl esters, sulfonic acid derivatives, phosphate esters, phenols Nonionic photolatent cationic polymerization catalysts such as sulfonic acid ester, diazonaphthoquinone, N-hydroxyimide sulfonate and the like. These photolatent cationic polymerization catalysts may be used alone or in combination of two or more.
[0036]
The thermosetting polyimide resin is a resin having an imide bond in the polymer main chain.
The thermosetting polyimide resin is not particularly limited. For example, a condensation polymer of an aromatic diamine and an aromatic tetracarboxylic acid, a bismaleimide resin that is an addition polymer of an aromatic diamine and a bismaleimide, or an aminobenzoic acid. Examples thereof include polyamino bismaleimide resins, which are addition polymers of acid, hydrazide, and bismaleimide, and bismaleimide triazine resins composed of a dicyanate compound and a bismaleimide resin. Of these, bismaleimide triazine resin is preferably used. These thermosetting polyimide resins may be used alone or in combination of two or more.
[0037]
For example, various thermosetting resins, thermoplastic resins, rubbers (elastomers), and other compounds may be added to the thermosetting polyimide resin for appropriate resin modification. good.
[0038]
The thermosetting resin as the modifier is not particularly limited. For example, various epoxy resins, phenol resins, polyfunctional maleimide resins, polyfunctional (meth) acrylate resins; diallyl phthalate, trialkenyl isocyanate Examples thereof include polyalkenyl resins such as nurate; dicyclopentadiene resins and the like. These thermosetting resins may be used alone or in combination of two or more.
[0039]
The thermoplastic resin as the modifier is not particularly limited, and examples thereof include polyethylene, polypropylene, vinylidene chloride, polystyrene, ethylene fluoride, vinylidene fluoride, polyester, polyphenylene sulfide, polyester sulfone, polyacetal, and polycarbonate. . These thermoplastic resins may be used alone or in combination of two or more.
[0040]
The rubber (elastomer) as the modifier is not particularly limited, and examples thereof include ethylene-propylene copolymer rubber, butadiene-acrylonitrile copolymer rubber, butadiene rubber, and acrylic rubber. These rubbers (elastomers) may be used alone or in combination of two or more.
[0041]
The flame retardant thermosetting resin composition of the present invention preferably contains the epoxy resin or the thermosetting polyimide resin, and from a mixture of the epoxy resin and the thermosetting polyimide resin. It is preferable to contain resin which becomes.
[0042]
The layered silicate means a silicate mineral having an exchangeable cation between crystal layers. The layered silicate is not particularly limited, and examples thereof include smectite clay minerals such as montmorillonite, saponite, hectorite, beidellite, stevensite, nontronite, vermiculite, halloysite, and swelling mica. Among these, montmorillonite and / or swellable mica is preferably used. The layered silicate may be a natural product or a synthetic product. Moreover, these layered silicates may be used independently and 2 or more types may be used together.
[0043]
As the layered silicate, using a smectite clay mineral or swelling mica having a large shape anisotropy effect defined by the following formula (1) can improve the mechanical strength of the flame retardant thermosetting resin composition. This is more preferable from the viewpoint of improving gas barrier properties.
Shape anisotropy effect = area of crystal surface (A) / area of crystal surface (B) (1)
In the formula (1), the crystal surface (A) means the layer surface, and the crystal surface (B) means the layer side surface.
[0044]
The exchangeable cation existing between the crystal layers of the layered silicate is a metal ion such as sodium or calcium existing on the crystal surface, and these metal ions have a cation exchange property with a cationic substance. Various substances having cationic properties can be trapped (intercalated) between the crystal layers of the layered silicate.
[0045]
The cation exchange capacity of the layered silicate is not particularly limited, but a preferred lower limit is 50 milliequivalent / 100 g and an upper limit is 200 milliequivalent / 100 g. If the cation exchange capacity of the layered silicate is less than 50 milliequivalent / 100 g, the amount of the cationic substance intercalated between the crystal layers of the layered silicate due to cation exchange is reduced, so that there is sufficient space between the crystal layers. In some cases, it is not depolarized (hydrophobized), and when it exceeds 200 milliequivalents / 100 g, the bonding force between the crystal layers of the layered silicate becomes too strong, and the crystal flakes may be difficult to peel off.
[0046]
In the flame-retardant thermosetting resin composition of the present invention, when a low-polar resin or a non-polar resin is used as the thermosetting resin, the crystalline layer of the layered silicate is previously cationized with a cationic surfactant or a hindered amine compound. It is preferable to exchange and hydrophobize. By previously hydrophobizing the crystal layer of the layered silicate, the affinity between the layered silicate and the thermosetting resin is increased, and the layered silicate can be finely dispersed more uniformly in the thermosetting resin.
[0047]
The cationic surfactant is not particularly limited, and examples thereof include quaternary ammonium salts and quaternary phosphonium salts. Among them, a quaternary ammonium salt (alkyl ammonium ion) having an alkyl chain having 6 or more carbon atoms is preferably used because it can sufficiently depolarize the crystal layer of the layered silicate.
[0048]
The quaternary ammonium salt is not particularly limited, and examples thereof include lauryl trimethyl ammonium salt, stearyl trimethyl ammonium salt, trioctyl ammonium salt, distearyl dimethyl ammonium salt, di-cured tallow dimethyl ammonium salt, and distearyl dibenzyl ammonium salt. Can be mentioned. These quaternary ammonium salts may be used alone or in combination of two or more.
[0049]
The quaternary phosphonium salt is not particularly limited. For example, dodecyl triphenyl phosphonium salt, methyl triphenyl phosphonium salt, lauryl trimethyl phosphonium salt, stearyl trimethyl phosphonium salt, trioctyl phosphonium salt, distearyl dimethyl phosphonium salt, distearyl di Examples thereof include benzylphosphonium salts. These quaternary phosphonium salts may be used alone or in combination of two or more.
[0050]
The hindered amine compound has a structure in which all hydrogen atoms on the 2nd and 6th carbons of piperidine are substituted with methyl groups, as represented by the following general formula (2).
[0051]
[Chemical 1]

[0052]
In the formula, R and R ′ each independently represents an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, an allyl group, a substituted allyl group, a hydrogen atom, a halogen atom, or from R and R ′. At least one of the combinations represents a bonded hydrocarbon group or a functional group in which a part of carbon atoms of the hydrocarbon group is substituted with a nitrogen atom, a sulfur atom, an oxygen atom or a silicon atom.
[0053]
It does not specifically limit as said hindered amine type compound, Well-known various hindered amine type compounds are mentioned. These hindered amine compounds may be used alone or in combination of two or more.
The hindered amine-based compound functions as a radical scavenger, imparts excellent light resistance to the flame retardant thermosetting resin composition during non-combustion, and captures active radicals generated during the combustion process during combustion. And can be stabilized. Accordingly, as the hindered amine compound, it is preferable to use a compound having excellent high temperature stability such as a high decomposition temperature. Specific examples of such hindered amine compounds having excellent high temperature stability include N-alkoxy hindered amines represented by the following general formula (3).
[0054]
[Chemical 2]

[0055]
In the formula, R represents a structure represented by the following formula (4).
[0056]
[Chemical 3]

[0057]
Among the above-mentioned hindered amine compounds, commercially available products include, for example, the product name “Sanol” series manufactured by Sankyo Co., Ltd., the product name “Adeka Stub” series manufactured by Asahi Denka Kogyo Co., Ltd., and the product name “Sumithorpe” manufactured by Sumitomo Chemical Co., Ltd. ”Series, brand name“ Biosoap ”series manufactured by Kyodo Yakuhin Co., Ltd., product name“ Chimasorb ”series and product name“ Tinuvin ”series manufactured by Ciba Specialties, product name“ Goodrite ”series manufactured by Goodrich, and product manufactured by BASF Names such as “Yubinar” series. These commercially available hindered amine compounds may be used alone or in combination of two or more.
[0058]
The layered silicate used in the present invention can improve the dispersibility in the thermosetting resin used in the present invention by chemical treatment as described above.
The chemical treatment is not limited to the cation exchange method (hereinafter also referred to as chemical modification (1) method) using a cationic surfactant or a hindered amine compound, and includes, for example, chemical modification (2) to chemical shown below. The modification (6) can also be carried out by various chemical treatment methods. These chemical modification methods may be used alone or in combination of two or more. In addition, the layered silicate whose dispersibility in the thermoplastic resin and / or the thermosetting resin is improved by the following various chemical treatment methods including the chemical modification (1) method is hereinafter referred to as “organized layered layer”. Also called “silicate”.
[0059]
In the chemical modification (2) method, a hydroxyl group present on the crystal surface of the organically modified layered silicate chemically treated by the chemical modification (1) method can be combined with a functional group or a chemical bond. In this method, chemical treatment is performed with a compound having at least one functional group having high chemical affinity at the molecular end.
[0060]
In the chemical modification (3) method, a hydroxyl group present on the crystal surface of the organically modified layered silicate chemically treated by the chemical modification (1) method can be chemically bonded to a functional group or a chemical bond. In this method, chemical treatment is performed with a compound having one or more functional groups and reactive functional groups having high chemical affinity at the molecular ends.
[0061]
The chemical modification (4) method is a method in which the crystallized surface of the organically modified layered silicate chemically treated by the chemical modification (1) method is chemically treated with a compound having an anionic surface activity.
[0062]
The chemical modification (5) method is a chemical treatment (4) method in which a chemical treatment is performed with a compound having one or more reactive functional groups in addition to the anion site in the molecular chain of the compound having anionic surface activity.
[0063]
In the chemical modification (6) method, the organically modified layered silicate chemically treated by any one of the chemical modification (1) method to the chemical modification (5) method is further used, for example, maleic anhydride-modified polyphenylene ether type. This is a method using a composition to which a resin having a functional group capable of reacting with a layered silicate such as a resin is added.
[0064]
In the chemical modification (2) method, the functional group that can be chemically bonded to the hydroxyl group or the functional group having a large chemical affinity without chemical bonding is not particularly limited, and examples thereof include an alkoxy group, a glycidyl group, and a carboxyl group. Groups (including dibasic acid anhydrides), hydroxyl groups, isocyanate groups, aldehyde groups and other functional groups, and other functional groups having high chemical affinity with hydroxyl groups. In addition, the functional group that can be chemically bonded to the hydroxyl group, or a compound having a functional group with high chemical affinity without chemical bonding is not particularly limited. Examples thereof include silane compounds having a group, titanate compounds, glycidyl compounds, carboxylic acids, alcohols and the like. These compounds may be used independently and 2 or more types may be used together.
[0065]
The silane compound is not particularly limited. For example, vinyltrimethoxysilane,
Vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropyldimethylmethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyl Methyldiethoxysilane, γ-aminopropyldimethylethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, N-β- (aminoethyl) γ-aminopropyltrimethoxy Silane, N-β- (aminoethyl) γ-aminopropyltriethoxysilane, N-β- (aminoethyl) γ-aminopropylmethyldimethoxysilane, octadecyltrimethoxysilane, oct Decyl triethoxysilane, .gamma.-methacryloxypropyl methyl dimethoxy silane, .gamma.-methacryloxypropyl methyl diethoxy silane, .gamma.-methacryloxypropyl trimethoxysilane, .gamma.-methacryloxypropyl triethoxysilane, and the like. These silane compounds may be used alone or in combination of two or more.
[0066]
In the chemical modification (4) method and the chemical modification (5) method, as a compound having an anionic surface activity, a compound having an anionic surface activity and having one or more reactive functional groups in addition to the anion site in the molecular chain The layer silicate is not particularly limited as long as it can be chemically treated by ionic interaction, for example, sodium laurate, sodium stearate, sodium oleate, higher alcohol sulfate, secondary higher alcohol sulfate, Examples thereof include unsaturated alcohol sulfate salts. These compounds may be used independently and 2 or more types may be used together.
[0067]
In the flame retardant thermosetting resin composition of the present invention, the layered silicate has an average interlayer distance of (001) plane measured by a wide angle X-ray diffraction measurement method of 3 nm or more, and part or all of Preferably, the average interlayer distance is 3 nm or more and 5 nm or less, and part or all of the average interlayer distance is dispersed in 5 layers or less.
In the present specification, the average interlayer distance of the layered silicate means an average interlayer distance when the layered silicate fine flaky crystal is used as a layer, and X-ray diffraction peak and transmission electron microscope photography, It can be calculated by a wide-angle X-ray diffraction measurement method.
[0068]
That the average interlayer distance of the layered silicate is 3 nm or more means that the interlayer of the layered silicate is cleaved to 3 nm or more, and part or all of the layered silicate is 5 layers or less. Dispersing in a layer means that part or all of the layered silicate laminate is dispersed. These all mean that the interaction between layered silicate layers is weakened.
[0069]
When the average interlayer distance of the layered silicate is 3 nm or more and part or all of the layered silicate is dispersed in 5 layers or less, the layered silicate is obtained by blending and dispersing the layered silicate in the thermosetting resin. The flame retardant thermosetting resin composition exhibits excellent performances such as flame retardancy, mechanical properties, high temperature properties, heat resistance, and dimensional stability. If the average interlayer distance is less than 3 nm, the effect of dispersion of the layered silicate on the nanometer scale cannot be obtained sufficiently, and the improvement of mechanical properties and flame retardancy is in the same range as when combining ordinary inorganic fillers. stay. The more preferable lower limit of the average interlayer distance is 3 nm, and the upper limit is 5 nm. When the average interlaminar distance exceeds 5 nm, the lamellar silicate crystal flakes separate into layers and the interaction of the lamellar silicate weakens to a negligible level, resulting in a slower film formation rate during combustion and improved flame retardancy May not be sufficiently obtained.
[0070]
That part or all of the layered silicate is dispersed in 5 layers or less specifically means that 10% or more of the layered silicate is preferably dispersed in 5 layers or less. More preferably, 20% or more of the layered silicate is dispersed in 5 layers or less. In addition, the dispersion state of the layered silicate is observed with a transmission electron microscope at 50,000 to 100,000 times, and is the total number of layers (X) of the layered assembly of layered silicate that can be observed in a certain area. The number of layers (Y) of the laminated assembly dispersed in 5 layers or less can be measured and calculated by the following formula (5).
Ratio of layered silicate dispersed in 5 layers or less (%) = (Y / X) × 100 (5)
[0071]
The number of layered silicate layers is preferably divided into 5 layers or less, whereby the above effect can be obtained, but more preferably 3 layers or less. Particularly preferably, it is thinned into a single layer.
[0072]
In the resin composition of the present invention, the average interlayer distance of the layered silicate is 3 nm or more, and a part or all of the layered silicate is dispersed in 5 layers or less, that is, in the thermosetting resin. If the layered silicate is highly dispersed, the interface area between the thermosetting resin and the layered silicate increases, and the average distance between the crystal flakes of the layered silicate decreases.
[0073]
When the interface area between the thermosetting resin and the layered silicate increases, the degree of restraint of the thermosetting resin on the surface of the layered silicate increases, and mechanical properties such as elastic modulus improve. Moreover, when the degree of restraint of the thermosetting resin on the surface of the layered silicate increases, the melt viscosity increases and the moldability also improves. Furthermore, gas molecules are much easier to diffuse in polymers compared to inorganic materials, so when gas molecules diffuse in thermosetting resins, they diffuse while bypassing inorganic materials, so gas barrier properties are also manifested. It becomes possible.
[0074]
More specifically, when the degree of restraint of the thermosetting resin on the surface of the layered silicate is increased, the mechanical properties are improved in a wide temperature range from room temperature to high temperature. Surprisingly, the mechanical properties can be maintained even in the high temperature region above the glass transition point and melting point of the resin. As a result, the coefficient of linear expansion at high temperatures can be kept low. The reason for this is not clear, but it is considered that even in the region of the glass transition point or the melting point or higher, the finely dispersed layered silicate acts as a kind of pseudo-crosslinking point, so that these physical properties are expressed.
[0075]
As for the gas barrier property, not only the solvent resistance, hygroscopicity and water absorption are improved, but also the barrier property of substances other than gas molecules is exhibited. For example, in a multilayer printed wiring board which is one of the uses of the flame retardant thermosetting resin composition of the present invention, copper migration from a copper circuit may be a problem, but this is also suppressed. Furthermore, in these materials, even a trace amount additive added to the material may cause defects such as poor plating by bleeding out to the surface, but the additive bleeding hardly occurs.
[0076]
On the other hand, when the average distance between the lamellar silicate crystal flakes becomes small, it becomes easier to form a sintered body due to the movement of the lamellar silicate crystal flakes during combustion. That is, the resin composition in which the lamellar silicate crystal flakes are dispersed so that the average interlayer distance is 3 nm or more is easy to form a sintered body that can be a flame retardant coating. Since this sintered body is formed at an early stage during combustion, not only the supply of oxygen from the outside world can be blocked, but also the flammable gas generated by the combustion can be blocked, and the resin composition is excellent. Expresses flame retardancy.
[0077]
In the flame-retardant thermosetting resin composition of the present invention, the lower limit of the amount of the layered silicate added to 100 parts by weight of the thermosetting resin is 1 part by weight, and the upper limit is 40 parts by weight. If it is less than 1 part by weight, it becomes difficult to form a sintered body that can be a flame retardant coating, and the flame retardant effect is small. If it exceeds 40 parts by weight, the density of the obtained flame retardant thermosetting resin composition Since (specific gravity) becomes high and flexibility with respect to bending is lacking, practicality is lost. The preferred lower limit is 2 parts by weight and the upper limit is 20 parts by weight.
[0078]
The means for dispersing the layered silicate in the thermosetting resin is not particularly limited. For example, the method using the organically modified layered silicate, foaming after mixing the thermosetting resin and the layered silicate by a conventional method. And a method using a block copolymer as a dispersant. By using these dispersion methods, the layered silicate can be more uniformly and finely dispersed in the thermosetting resin.
[0079]
The non-halogen flame retardant is not particularly limited as long as it can impart flame retardancy to the thermosetting resin. For example, magnesium hydroxide, aluminum hydroxide, dawsonite, calcium aluminate, 2 water Examples thereof include metal hydroxides such as Japanese gypsum and calcium hydroxide. Of these, magnesium hydroxide and aluminum hydroxide are preferably used.
The metal hydroxide is preferably subjected to surface treatment with various surface treatment agents. The surface treatment agent is not particularly limited, and examples thereof include fatty acid surface treatment agents, silane coupling agents, titanate coupling agents, polyvinyl alcohol surface treatment agents, and epoxy surface treatment agents. Among these, since a low water-absorbing flame retardant thermoplastic resin composition can be obtained, a fatty acid surface treatment agent, a silane coupling agent, a titanate coupling agent, and an epoxy surface treatment agent are preferably used. Of these, fatty acid-based surface treating agents and epoxy-based surface treating agents are more preferably used. These metal hydroxides may be used alone or in combination of two or more. When two or more kinds of metal hydroxides are used in combination, each metal hydroxide starts an endothermic dehydration reaction (decomposition dehydration reaction) at a different temperature, so that a higher flame retardant effect is obtained.
[0080]
The metal hydroxide has an effect of lowering the temperature of the combustion field and extinguishing the fire by desorbing heat and releasing water molecules by causing an endothermic dehydration reaction under high heat during combustion. In the flame retardant thermosetting resin composition of the present invention, the flame retardant effect due to the metal hydroxide is increased by adding a layered silicate. This is considered to be due to the concerted effect of the flame retardant effect due to the formation of the coating during combustion of the layered silicate and the flame retardant effect due to the endothermic dehydration reaction of the metal hydroxide.
[0081]
In the flame-retardant thermosetting resin composition of the present invention, the lower limit of the blending amount of the non-halogen flame retardant with respect to 100 parts by weight of the thermosetting resin is 5 parts by weight, and the upper limit is 100 parts by weight. When the amount is less than 5 parts by weight, it is difficult to exert a sufficient flame retardant effect. When the amount exceeds 100 parts by weight, the flame retardant effect is exhibited, but an increase in density (specific gravity), lack of flexibility, an increase in water absorption rate, Demerits such as deterioration of dielectric properties and insulation occur. The preferred lower limit is 20 parts by weight and the upper limit is 60 parts by weight. Within this range, the flame retardant thermosetting resin composition can be suitably used as an insulating substrate material, not a region that causes problems in material properties such as mechanical strength and electrical characteristics.
[0082]
The flame retardant thermosetting resin composition of the present invention preferably further contains a flame retardant aid. By blending the flame retardant aid, the oxygen index can be improved and the maximum heat generation rate can be greatly reduced.
Examples of the flame retardant aid include at least one flame retardant selected from the group consisting of hindered amine compounds, fluororesins, silicone oils, hydrotalcite compounds, metal oxides, and silicone-acrylic composite rubbers. Auxiliaries are preferably used. By using these flame retardant aids, decomposition of the thermosetting resin can be prevented and the maximum heat generation rate can be suppressed.
[0083]
The hindered amine compound is a compound having a structure represented by the general formula (2) as described above. The hindered amine-based compound functions as a radical scavenger, imparts excellent light resistance to the flame retardant thermosetting resin composition during non-combustion, and captures active radicals generated during the combustion process during combustion. And can be stabilized. Accordingly, as the hindered amine compound, it is preferable to use a compound having excellent high temperature stability such as a high decomposition temperature. Examples of such hindered amine compounds having excellent high temperature stability include N-alkoxy hindered amines represented by the general formula (3).
[0084]
In the flame retardant thermosetting resin composition of the present invention, the flame retardant effect by the hindered amine compound is increased by blending the layered silicate. This is considered to be due to the fact that the flame retardant effect due to film formation during combustion of the layered silicate and the flame retardant effect due to the radical stabilization reaction of the hindered amine compound occur in concert, and each effect is promoted. In addition, when used in combination with a metal hydroxide such as magnesium hydroxide used as a non-halogen flame retardant, the flame retardant effect due to the endothermic dehydration reaction of the metal hydroxide and the radical stabilization reaction of the hindered amine compound are difficult. A synergistic effect with the fuel effect is great, which is preferable.
[0085]
The above-mentioned fluororesin effectively suppresses the dropping (drip) of the molten resin by improving the melt viscosity of the flame retardant thermosetting resin composition melted at the time of combustion, thereby preventing the spread of fire. Can be granted. Furthermore, this prevents the formation of a sintered film from the layered silicate during combustion, thereby improving flame retardancy. As the fluorine substitution amount increases, the fluororesin becomes harder to aggregate due to its rigidity in molecular structure. Further, it is known that a fluororesin takes a fibrous structure by stretching and becomes more rigid.
[0086]
The silicone oil or silicone-acrylic composite rubber is a strong protective material when it reacts with a polymer having an active group during combustion to promote char formation, or when a glassy inorganic compound film is formed. Thus, thermal decomposition of the thermosetting resin can be suppressed.
[0087]
In the flame retardant thermosetting resin of the present invention, the preferred lower limit of the blending amount of the flame retardant aid with respect to 100 parts by weight of the thermosetting resin is 0.1 part by weight, and the upper limit is 20 parts by weight. If it is less than 0.1 part by weight, it will be difficult to express good flame retardancy, and if it exceeds 20 parts by weight, the mechanical strength will be lowered or the flexibility for bending will be lost. May occur. A more preferred lower limit is 0.5 parts by weight and an upper limit is 15 parts by weight.
[0088]
In addition, when using a hindered amine type compound as the said flame-retardant adjuvant, the minimum with the preferable amount of the hindered amine type compound with respect to 100 weight part of thermosetting resins is 0.1 weight part, and an upper limit is 10 weight part. If it is less than 0.1 part by weight, it is difficult to develop good flame retardancy, and if it exceeds 10 parts by weight, the flame retarding effect may be lowered. A more preferred lower limit is 0.2 parts by weight and an upper limit is 4 parts by weight.
[0089]
If necessary, an additive may be further added to the flame retardant thermosetting resin composition of the present invention. The additive is not particularly limited, and examples thereof include an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a weathering agent, and a lubricant. These additives may be used alone or in combination of two or more.
[0090]
The method for producing the flame retardant thermosetting resin composition of the present invention is not particularly limited. For example, each predetermined compounding amount of a thermosetting resin, a layered silicate, a non-halogen flame retardant, and a flame retardant auxiliary is directly added. A method of blending and mixing, and after adding and mixing a layered silicate and a flame retardant aid in a predetermined amount or more to a thermosetting resin to prepare a masterbatch, the prepared masterbatch has a predetermined amount A so-called masterbatch method, in which a thermosetting resin and a non-halogen flame retardant are added and diluted so as to be, can be mentioned.
[0091]
There are no particular limitations on the mixing method for producing the flame retardant thermosetting resin composition, and various methods can be used. Examples include thermosetting resins, layered silicates, non-halogen flame retardants, and flame retardants. A method of melt-kneading the flame retardant with an extruder, two rolls, a Banbury mixer, etc., or an organic solvent in which the thermosetting resin, layered silicate, non-halogen flame retardant and flame retardant aid are dissolved or dispersed. The method of mixing in them is mentioned.
[0092]
The flame retardant thermosetting resin composition of the present invention is 50 kW / m in accordance with ASTM E 1354. ² The maximum heat generation rate when heated and burned for 30 minutes under radiant heating conditions of 350 kW / m ² The following is preferable. 350kW / m ² Is enough
Flame retardant properties may not be achieved. More preferably 300 kW / m ² It is as follows. In many cases, the flame retardant thermosetting resin composition having the maximum heat generation rate satisfying this condition can satisfy the V-0 certification level in the combustion test method defined in UL94.
[0093]
The flame retardant thermosetting resin composition of the present invention is 50 kW / m in accordance with ASTM E 1354. ² It is preferable that the yield point stress is 4.9 kPa or more when the combustion residue obtained by heating and burning for 30 minutes under the radiant heating condition is compressed at 0.1 cm / second. If it is less than 4.9 kPa, the combustion residue easily collapses due to a slight impact, and there may be a risk of re-ignition from a high-voltage part due to damage of parts during a fire.
[0094]
The flame-retardant thermosetting resin composition of the present invention is suitable as a material for an insulating substrate used in electronic devices such as computers. By using the flame retardant thermosetting resin composition of the present invention as an insulating substrate material, it is possible to obtain an insulating substrate material that has high flame retardancy, does not discharge harmful substances when discarded, and does not burden the environment. .
[0095]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.
[0096]
( reference Example 1)
100 parts by weight of a bisphenol A type epoxy resin (manufactured by Dow Chemical Japan Co., Ltd., trade name “D.E.R.331L”), 2.5 parts by weight of dicyandiamide as a curing agent and 0.1 of 2-ethyl-4-methylimidazole Swellable fluorine mica (trade name “Somasif MAE-100” manufactured by Co-op Chemical Co., Ltd.) 7.7 organically treated with distearyldimethyl quaternary ammonium salt with respect to 92.3 parts by weight of the epoxy resin composition composed of parts by weight 50 parts by weight of magnesium hydroxide (trade name “Kisuma 5J”, manufactured by Kyowa Chemical Industry Co., Ltd.) with fatty acid surface treatment is blended, kneaded for 1 hour with a stirring raikai machine, defoamed, and liquid flame retardant An epoxy resin composition was prepared.
The obtained flame-retardant epoxy resin composition was heated at 140 ° C. for 1 hour, then cured by heating at 170 ° C. for 2 hours, molded into a plate-like material, and an evaluation sample was produced.
[0097]
( Implementation Example 1 )
55 parts by weight of bisphenol A type epoxy resin “D.E.R. 331L”, 15 parts by weight of BT resin (trade name “BT2100B”, manufactured by Mitsubishi Gas Chemical Company), 15 parts by weight of neopentyl glycol diglycidyl ether, coupling agent As γ-glycidoxypropyltrimethoxysilane (manufactured by Nihon Unicar Co., Ltd., trade name “A-187”) and 1.0 part by weight of acetylacetone iron (manufactured by Nippon Chemical Industry Co., Ltd.) as a curing catalyst. 7.7 parts by weight of swelling fluorine mica “Somasif MAE-100” organically treated with distearyldimethyl quaternary ammonium salt with respect to 92.3 parts of resin composition and magnesium hydroxide “Kisuma 5J” treated with fatty acid surface 50 parts by weight is blended, kneaded for 1 hour with a stirring laika machine, defoamed, and a liquid flame retardant thermosetting resin composition It was produced.
The obtained flame-retardant thermosetting resin composition was heated at 110 ° C. for 3 hours, then cured by heating at 160 ° C. for 3 hours, and formed into a plate-like material to prepare an evaluation sample.
[0098]
(Reference example 2 )
Further, a liquid flame retardant epoxy resin composition was produced in the same manner as in Reference Example 1 except that 3 parts by weight of a hindered amine compound (manufactured by BASF, trade name “Ubinal 5050H”) was blended as a flame retardant aid. The sample for evaluation was produced using this.
[0099]
( reference Example 3 )
45 parts by weight of bisphenol A type epoxy resin (manufactured by Dow Chemical Japan Co., Ltd., DER 331L), 45 parts by weight of solid epoxy resin (manufactured by Tohto Kasei Co., Ltd., YP55), dicyandiamide (manufactured by Adeka Corp., Adeka Hardener EH- 3636) 3.15 parts by weight, modified imidazole (manufactured by Adeka, Adeka Hardener EH-3366) 94.5 parts by weight of an epoxy resin composition, organically formed with trioctylmethylammonium salt as a layered silicate 10 parts by weight of synthetic hectorite (Corp Chemical Co., Lucentite STN) subjected to treatment, 70 weight of magnesium hydroxide (Kyowa Chemical Industry Co., Ltd., Kisuma 5P) surface-treated with a silane coupling agent as a flame retardant And 500 parts by weight of DMF (made by Wako Pure Chemical Industries, special grade) as an organic solvent After stirring for 1 hour at a stirrer, was deaerated to obtain a resin / layered silicate solution. Next, after removing the solvent in a state where the obtained resin / layered silicate solution is put in a mold or coated on a sheet of polyethylene terephthalate, it is heated at 110 ° C. for 3 hours, and further heated at 170 ° C. for 30 minutes. Then, it was cured and formed into a plate-like material to produce a sample for evaluation.
[0100]
(Comparative Example 1)
Except that swellable fluorine mica "Somasif MAE-100" organically treated with distearyldimethyl quaternary ammonium salt was not blended reference In the same manner as in Example 1, a liquid flame-retardant epoxy resin composition was produced, and a sample for evaluation was produced using the composition.
[0101]
(Comparative Example 2)
Except that swellable fluorine mica "Somasif MAE-100" organically treated with distearyldimethyl quaternary ammonium salt was not blended Implementation Example 1 In the same manner as above, a liquid flame retardant thermosetting resin composition was produced, and an evaluation sample was produced using the liquid flame retardant thermosetting resin composition.
[0102]
(Comparative Example 3)
Reference example except that swellable fluorine mica "Somasif MAE-100" organically treated with distearyldimethyl quaternary ammonium salt was not blended 2 In the same manner as above, a liquid flame-retardant epoxy resin composition was produced, and an evaluation sample was produced using this.
[0103]
Example 1 Reference examples 1 to 3 And for the samples for evaluation obtained in Comparative Examples 1 to 3, by the following method, the average interlayer distance of the layered silicate, the peeled state of the layered silicate layer, the oxygen index, the maximum heat generation rate, the yield point stress of the combustion residue, Drip resistance and water absorption were evaluated.
The results are shown in Table 1.
[0104]
(Measurement of average interlayer distance of layered silicate)
Using an X-ray diffractometer (trade name “RINT1100”, manufactured by Rigaku Corporation), 2θ of the diffraction peak obtained from diffraction of the layered surface of the layered silicate in the sample for evaluation is measured. Thus, the (001) spacing (d) of the layered silicate was calculated, and the obtained d was defined as the average interlayer distance (nm).
λ = 2 dsin θ
In the formula, d represents the interplanar spacing of the layered silicate, θ represents the diffraction angle, and λ was 1.54.
[0105]
(Evaluation of peeled state of layered silicate layer)
A photograph was taken using a transmission electron microscope (trade name “JEM-1200EXII” manufactured by JEOL Ltd.), the peeled state of the layered silicate layer in the sample for evaluation was observed, and the layered silicate was observed according to the following criteria. The peeled state of the layer was evaluated.
◎ …… 20% or more of the number of layered silicates existed in 5 layers or less.
○ ………… Dispersed including those existing in 5 layers or less.
X ... All existed in a state exceeding 5 layers.
[0106]
(Measurement of oxygen index)
In accordance with ASTM D 2863 “Standard test method for plastic flammability by oxygen index”, a test piece consisting of a sample for evaluation (length 70 mm × width 6 mm × thickness 3 mm) was conducted independently to perform a combustion test. . The numerical value of the minimum oxygen concentration expressed by the volume% in the mixed gas of oxygen and nitrogen necessary for the test piece to continue burning is called the oxygen index, and when the test piece is burned at a predetermined oxygen concentration, When it continued to burn for 3 minutes or more, or it burned 50 mm or more within 3 minutes, it was judged that combustion could be continued, and the oxygen concentration at that time was made into the oxygen index of a test piece.
[0107]
(Measurement of maximum exotherm rate and yield point stress of combustion residue)
In accordance with ASTM E 1354 “Building Material Flammability Test Method”, a test piece (100 mm × 100 mm × thickness 3 mm) consisting of a sample for evaluation is applied to a 50 kW / m by a cone calorimeter. ² It was burned by irradiating the heat rays. At this time, the maximum heat generation rate of the test piece (kW / m ² ) Was measured. The faster the maximum heat generation rate, the shorter the initial ignition time and the easier the ignition.
Also, using a handy compression tester (trade name “KES-G5” manufactured by Kato Tech Co., Ltd.), compress the combustion residue of the test piece at 0.1 cm / second and measure the yield point stress (kPa) of the combustion residue. did.
[0108]
(Drip resistance evaluation)
The upper part of the test piece (length 127mm x width 12.7mm x thickness 0.8mm) consisting of the sample for evaluation is fixed with a clamp, and the lower bottom surface of the test piece is ignited, so that the combustion test piece cannot maintain its shape. , And observed whether a part of it dropped out. Specifically, a surgical cotton is placed 20 cm directly under the test piece, and during the test, it is visually observed whether or not the surgical cotton is ignited by a combustion dropout from the combustion test piece. evaluated.
○ …… The surgical cotton did not ignite.
× …… The surgical cotton ignited.
[0109]
(Measurement of water absorption)
A test piece (length 10 mm × width 10 mm × thickness 0.8 mm) made of an evaluation sample was immersed in boiling water for 1 hour and weighed before and after the test to measure water absorption.
[0110]
[Table 1]

[0111]
【The invention's effect】
Since the flame-retardant thermosetting resin composition of the present invention has the above-described configuration, a sintered body is formed during combustion, and the shape of the combustion residue is maintained. As a result, shape collapse does not occur even after combustion, and fire spread can be prevented. In addition, the production of a strong sintered body can impart flame retardancy without adding a large amount of flame retardant, and therefore there is little decrease in material properties such as mechanical strength, toughness, dielectric properties, and insulation. Such characteristics can prevent the occurrence of a fire, and the disposal after disposal can be performed safely and inexpensively.

Claims (9)

  It contains 100 parts by weight of a resin composed of a mixture of an epoxy resin and a thermosetting polyimide resin, 1 to 40 parts by weight of a layered silicate, and 5 to 100 parts by weight of a non-halogen flame retardant. Flame curable resin composition.   The flame retardant thermosetting resin composition according to claim 1, wherein the thermosetting polyimide resin is a bismaleimide triazine resin.   The flame retardant thermosetting resin composition according to claim 1 or 2, wherein the layered silicate is montmorillonite and / or swellable mica.   The flame retardant thermosetting resin composition according to claim 1, 2 or 3, wherein the layered silicate contains an alkyl ammonium ion having 6 or more carbon atoms and / or a hindered amine compound.   The layered silicate has an average interlayer distance of (001) plane measured by a wide angle X-ray diffraction measurement method of 3 nm or more, and a part or all of them are dispersed in 5 layers or less. The flame retardant thermosetting resin composition according to 1, 2, 3 or 4.   The flame retardant thermosetting resin composition according to claim 1, 2, 3, 4, or 5, wherein the non-halogen flame retardant is a metal hydroxide.   The metal hydroxide is characterized in that it is surface-treated with one or more selected from the group consisting of fatty acid-based surface treatment agents, silane coupling agents, titanate coupling agents, and epoxy-based surface treatment fatty acids. The flame retardant thermosetting resin composition according to claim 6. In accordance with ASTM E 1354, the maximum heat generation rate when heated and burned for 30 minutes under radiant heating conditions of 50 kW / m ² is 350 kW / m ² or less. The flame retardant thermosetting resin composition according to 4, 5, 6 or 7 . According to ASTM E 1354, the yield point stress when compressing the combustion residue obtained by heating and burning for 30 minutes under 50 kW / m ² of radiant heating conditions at 0.1 cm / second is 4.9 kPa or more The flame retardant thermosetting resin composition according to claim 1, 2, 3, 4, 5, 6, 7 or 8 .