JP4026275B2 - Active energy ray-curable resin composition, cured film thereof, and antireflection film - Google Patents

Description

【００２９】
［一般式（２）中、ｙは、６０〜１５０の整数であり、ｚは、６〜１０の整数である。］
【００３０】
また、アゾ基含有ポリシロキサン化合物の使用量を、ヘキサフルオロプロピレンおよびその共重合モノマの合計量１００重量部に対して、０．０１〜２０重量部の範囲内の値とするのが好ましい。この理由は、アゾ基含有ポリシロキサン化合物の使用量が０．０１重量部未満となると、ヘキサフルオロプロピレン共重合体が得られない場合があるためであり、一方、アゾ基含有ポリシロキサン化合物の使用量が２０重量部を超えると、得られるヘキサフルオロプロピレン共重合体の分子量が著しく低下する場合があるためである。
したがって、このような重合性の観点からアゾ基含有ポリシロキサン化合物の使用量を、ヘキサフルオロプロピレンおよびその共重合モノマの合計量１００重量部に対して、０．１〜１５重量部の範囲内の値とするのがより好ましく、１〜１０重量部の範囲内の値とするのがさらに好ましい。
【００３１】
（他のラジカル重合開始剤）
なお、重合速度を制御することからアゾ基含有ポリシロキサン化合物以外のラジカル重合開始剤、例えば、ジアシルパーオキサイド類、ケトンパーオキサイド類、ハイドロパーオキサイド類、ジアルキルパーオキサイド類、パーオキシエステル類、アゾ系化合物、過硫酸塩の一種単独または二種以上の組み合わせが挙げられる。
また、必要に応じて亜硫酸水素ナトリウム、ピロ亜硫酸ナトリウムなどの無機還元剤、ナフテン酸コバルト、ジメチルアニリンなどの有機還元剤を併用することも好ましい。このように組み合わせて使用することにより素早いラジカル反応を生じさせることができる。
さらに、ヨウ素含有フッ素化合物を単独、もしくは上述した有機過酸化物、アゾ系化合物あるいは過硫酸塩と併用して好適に用いることができる。
【００３２】
（ノニオン性反応性乳化剤）
また、第１の実施形態では、ヘキサフルオロプロピレン共重合体の重合の際に、ノニオン性反応性乳化剤を使用することを特徴としている。この理由は、シロキサン結合を含むヘキサフルオロプロピレン共重合体と、α−フルオロアクリレートモノマとの相溶性をさらに良好とするためである。
このようなノニオン性反応性乳化剤としては、例えば、下記一般式（３）で表される乳化剤を挙げることができ、市販のノニオン性反応性乳化剤としては、アデカリアソ−プＮＥ−３０（旭電化工業（株）製）等が挙げられる。
【００３３】
【化２】

【００３４】
［一般式（３）中、ｎは１〜２０の整数、ｍは１〜１０の整数、ｕは１０〜１００の整数である。］
【００３５】
なお、ノニオン性反応性乳化剤の使用量を、ヘキサフルオロプロピレンおよびその共重合モノマの合計量１００重量部に対して、０．０１〜１５重量部の範囲内の値とするのが好ましい。この理由は、ノニオン性反応性乳化剤の使用量が０．０１重量部未満となると、添加効果が得られない場合があるためであり、一方、ノニオン性反応性乳化剤の使用量が１５重量部を超えると、得られる含フッ素共重合体に一般的な再沈処理を施して、精製処理が出来ない場合があるためである。すなわち、ノニオン性反応性乳化剤が多量に存在すると、含フッ素共重合体を凝固させることが困難となる場合があるためである。
したがって、ノニオン性反応性乳化剤の使用量を、ヘキサフルオロプロピレンおよびその共重合モノマの合計量１００重量部に対して、０．１〜１０重量部の範囲内の値とするのがより好ましく、１〜５重量部の範囲内の値とするのがさらに好ましい。
【００３６】
（２）α−フルオロアクリレートモノマ
▲１▼種類
本発明に用いられるα−フルオロアクリレートモノマは、α位置にフッ素原子を有するアクリレートであれば特に制限されることなく、広い種類を使用することができる。α−フルオロアクリレートモノマは、ヘキサフルオロプロピレン共重合体と特異的に相溶することができる。また、α−フルオロアクリレートモノマは、ヘキサフルオロプロピレン共重合体と混合した場合であっても素早く放射線重合が可能であり、したがって、重合することにより高いガラス転移点や優れた機械的特性を示すことができる。
なお、このようなα−フルオロアクリレートモノマは、たとえば特開昭５０−５２０１９号公報に開示された製造方法（メチルエステル化反応およびエステル交換反応）により得ることができる。
【００３７】
また、好ましいα−フルオロアクリレートモノマとしては、上述した一般式（１）で表される化合物であることが好ましい。
より具体的には、トリフルオロエチルα−フルオロアクリレート、2,2,3,3−テトラフルオロプロピルα−フルオロアクリレート、ヘキサフルオロイソプロピルα−フルオロアクリレート、オクタフルオロペンチルα−フルオロアクリレート、ヘプタデカフルオロデシルα−フルオロアクリレート等の一種単独または二種以上の組み合わせが挙げられる。
【００３８】
また、α−フルオロアクリレートモノマとして、一般式（１）中のＲ_f主鎖に酸素原子が介入したもの、例えばＣＨ₂＝ＣＦ−ＣＯＯＣＦ₂Ｃ（ＣＦ₃）ＦＯＣＦ（ＣＦ₃）₃の構造式で表される化合物も好ましい。このようにＲ_f主鎖中に酸素原子が介入したα−フルオロアクリレートモノマは、比較的合成が容易であり、入手が容易なためである。
【００３９】
また、α−フルオロアクリレートモノマとして、下記一般式（４）や（５）で表されるジビニル化合物であることも好ましい。このようなジビニル化合物を用いることにより、得られる硬化膜の機械的強度をより高めることができるためである。
【００４０】
ＣＨ₂＝ＣＦＣＯＯ（ＣＨ₂）_x（ＣＦ₂）_y（ＣＨ₂）_xＯＣＯＦ＝ＣＨ₂ （４）
［一般式（４）中、ｘは１〜２、ｙは４〜１２の整数である。］
【００４１】
【化３】

【００４２】
［一般式（５）中、ｍおよびｎは０〜１０までの整数（ただし、同時に０とはならない。）、Ｒは水素または炭素数１〜１０までのアルキル基、Ｒ_fは一般式（１）と同様の内容である。］
【００４３】
▲２▼添加量
また、α−フルオロアクリレートモノマの添加量をヘキサフルオロプロピレン共重合体１００重量部に対して、１〜１０，０００重量部の範囲内の値とすることが好ましい。この理由は、α−フルオロアクリレートモノマの添加量が１重量部未満となると、硬化性が著しく低下する場合があるためであり、一方、α−フルオロアクリレートモノマの添加量が１０，０００重量部を超えると、組成物の粘度が低くなるため、所望の膜厚に形成するのが困難となったり、硬化膜の柔軟性や摺動性が低下する場合があるためである。
したがって、硬化性や硬化膜の特性のバランスがより良好となることから、α−フルオロアクリレートモノマの添加量をヘキサフルオロプロピレン共重合体１００重量部に対して、１０〜５，０００重量部の範囲内の値とすることがより好ましく、１００〜１，０００重量部の範囲内の値とすることがより好ましい。
【００４４】
（３）放射線重合開始剤
硬化性樹脂組成物には、放射線重合開始剤を含有させ、活性エネルギー線、例えば紫外線を照射することにより効率的に硬化させることができる。すなわち、放射線重合開始剤は、活性エネルギー線を受けることによってα−フルオロアクリレートモノマの重合反応を促進させる化合物である。
【００４５】
このような放射線重合開始剤の具体例として、１−ヒドロキシシクロヘキシルフェニルケトン、２，２'−ジメトキシ−２−フェニルアセトフェノン、キサントン、フルオレン、フルオレノン、ベンズアルデヒド、アントラキノン、トリフェニルアミン、カルバゾール、３−メチルアセトフェノン、４−クロロベンゾフェノン、４，４'−ジメトキシベンゾフェノン、４，４'−ジアミノベンゾフェノン、ミヒラーケトン、ベンゾイルプロピルエーテル、ベンゾインエチルエーテル、ベンジルジメチルケタール、１−（４−イソプロピルフェニル）−２−ヒドロキシ−２−メチルプロパン−１−オン、２−ヒドロキシ−２−メチル−１−フェニルプロパン−１−オン、チオキサントン、ジエチルチオキサントン、２−イソプロピルチオキサントン、２−クロロチオキサントン、２−メチル−１−［４−（メチルチオ）フェニル］−２−モルフォリノプロパン−１−オン、２，４，６−トリメチルベンゾイルジフェニルフォスフィンオキサイド、２−ベンジル−２−ジメチルアミノ−１−（４−モルフォリノフェニル）ブタン−１−オン、１−［４−（２−ヒドロキシエトキシ）−フェニル］−２−ヒドロキシ−２−メチルプロパン−１−オンなどの一種単独または２種以上の組み合わせを挙げることができる。これらのうち、２，４，６−トリメチルベンゾイルジフェニルフォスフィンオキサイド、１−ヒドロキシシクロヘキシルフェニルケトンがより好ましい。
【００４６】
また、放射線重合開始剤の使用量も特に制限されるものではないが、例えば、ヘキサフルオロ共重合体とα−フルオロアクリレートモノマとの合計量を１００重量部としたときに、０．１〜２０重量部の範囲内の値とするのが好ましい。この理由は、放射線重合開始剤の使用量が０．１重量部未満となると、α−フルオロアクリレートモノマの反応速度が遅くなったり、あるいは周囲に存在する酸素等の影響を受けやすくなる場合があるためである。一方、放射線重合開始剤の使用量が２０重量部を超えると、α−フルオロアクリレートモノマの分子量が低くなり、得られる硬化膜の機械的強度や耐熱性が低下する場合があるためである。したがって、α−フルオロアクリレートモノマの反応速度や硬化膜の特性等とのバランスがより良好となることから、放射線重合開始剤の使用量を０．５〜１０重量部の範囲内の値とするのがより好ましい。
【００４７】
（４）添加剤
本発明の組成物には、当該組成物の塗布特性、当該組成物の感光性、当該組成物による硬化膜の諸特性などの改善を目的として、各種の添加剤を含有することも好ましい。このような添加剤としては、例えば、ヘキサフルオロプロピレン共重合体以外のポリマー材料、顔料や染料などの着色剤、フィラー、酸化防止剤、紫外線吸収剤、光安定化剤、老化防止剤、シランカップリング剤、架橋性化合物、界面活性剤、重合禁止剤、溶剤などを挙げることができる。
【００４８】
より具体的には、好ましいポリマー材料としては、ポリメチル（メタ）アクリレートなどのアクリル樹脂、エポキシ樹脂、ノボラック樹脂、レゾール樹脂などを挙げることができる。
好ましい紫外線吸収剤としては、サリチル酸系紫外線吸収剤、ベンゾフェノン系紫外線吸収剤、ベンゾトリアゾール系紫外線吸収剤、シアノアクリレート系紫外線吸収剤などを挙げることができる。
好ましい老化防止剤としては、ジ−ｔｅｒｔ−ブチルフェノール、ピロガロール、ベンゾキノン、ヒドロキノン、ｎ−ブチルフェノール、ヒドロキノンモノプロピルエーテル、４，４'−［１−〔４−（１−（４−ヒドロキシフェニル）−１−メチルエチル）フェニル〕エチリデン］ジフェノール、１，１，３−トリス（２，５−ジメチル−４−ヒドロキシフェニル）−３−フェニルプロパン、ジフェニルアミン類、フェニレンジアミン類、フェノチアジン、メルカプトベンズイミダゾール等を挙げることができる。
【００４９】
また、好ましいシランカップリング剤としては、γ−アミノプロピルトリエトキシシラン、γ−メルカプトプロピルトリメトキシシラン、γ−メタアクリロキシプロピルトリメトキシシランなどを挙げることができる。
なお、上述した添加剤の添加量を、ヘキサフルオロ共重合体とα−フルオロアクリレートモノマとの合計量を１００重量部としたときに、それぞれ０．０１〜５重量部の範囲内の値とするのが好ましく、０．０１〜３重量部の範囲内の値とするのがさらに好ましい。この理由は、各種添加剤の添加量が０．０１重量部未満となると、添加効果が発現しない場合があるためであり、一方、各種添加剤の添加量が５重量部を超えると、得られる硬化性樹脂組成物の光硬化性が低下する場合があるためである。
【００５０】
また、架橋性化合物としては、メラミンなどのアミノ樹脂、ポリイソシアネート、多塩基酸、多塩基酸の無水物、ポリアミン、ポリオール、エポキシ化合物、エポキシ樹脂、水酸基含有化合物（例えばペンタエリスリトール、ポリフェノール、グリコール）など、ポリマー成分を構成する架橋性官能基と反応可能な基を有する化合物の中から一種またはニ種以上の組み合わせを添加することが好ましい。また、ポリマー成分の架橋性官能基と、架橋性化合物との反応（架橋反応）を促進するための反応触媒を組成物中に添加含有することも好ましい。
なお、架橋性化合物の添加量としては、本発明による効果が損なわれることなく、また、硬化性樹脂組成物から形成される硬化膜に好適な架橋構造を導入できることから、ポリマー成分を構成する架橋性官能基１当量あたり、０．５〜１．０当量の範囲内の値とするのが好ましく、０．７〜１．０当量の範囲内の値とするのがさらに好ましい。
【００５１】
また、界面活性剤は、硬化性樹脂組成物の塗布特性および帯電防止性を向上させることなどを目的として添加するのが好ましい。このような界面活性剤としては、アニオン系界面活性剤、カチオン系界面活性剤、ノニオン系界面活性剤などの公知の界面活性剤を挙げることができる。
なお、界面活性剤の添加量を、ヘキサフルオロプロピレン共重合体とα−フルオロアクリレートモノマとの合計量を１００重量部としたときに、０．０１〜５重量部の範囲内の値とするのが好ましく、０．０１〜３重量部の範囲内の値とするのがさらに好ましい。この理由は、界面活性剤の添加量が０．０１重量部未満となると、添加効果が発現しない場合があるためであり、一方、界面活性剤の添加量が５重量部を超えると、得られる硬化性樹脂組成物の耐水性や密着性が損なわれる場合があるためである。
【００５２】
また、溶剤を、硬化性樹脂組成物中の粘度を好ましい範囲内に調整し、塗布性を向上させることを目的として添加するのが好ましい。このような溶剤としては、酢酸エチル、酢酸ブチル、酢酸イソプロピル、酢酸イソブチル、酢酸セロソルブなどのエステル類；アセトン、メチルエチルケトン、メチルイソブチルケトン、シクロヘキサノンなどのケトン類；テトラヒドロフラン、ジオキサンなどの環状エーテル類；Ｎ，Ｎ−ジメチルホルムアミド、Ｎ，Ｎ−ジメチルアセトアミドなどのアミド類；トルエン、キシレンなどの芳香族炭化水素類を挙げることができ、これらと共に、アルコール類；脂肪族炭化水素類などを使用することも好ましい。
【００５３】
（５）硬化性樹脂組成物
▲１▼調製方法
本発明の硬化性樹脂組成物は、ヘキサフルオロプロピレン共重合体と、α−フルオロアクリレートモノマと、室温または加熱条件下で混合することにより調製することができる。具体的には、ミキサ、ボールミル、三本ロール等の混合機を用いて、容易に調製することができる。
【００５４】
▲２▼粘度
硬化性樹脂組成物の粘度は、ヘキサフルオロプロピレン共重合体の種類（モノマ組成）および分子量、並びにヘキサフルオロプロピレン共重合体の使用割合、さらには粘度調整剤（モノマ成分を含む）を適宜設定することにより、採用するコーティング法に応じた好ましい範囲内の値に調整することができる。例えば、硬化性樹脂組成物の粘度を１０〜１００，０００ｍＰａ・ｓ（測定温度２５℃）の範囲内の値に調整することが好ましい。
【００５５】
▲３▼硬化方法
硬化性樹脂組成物の硬化方法は特に制限されるものではないが、例えば、基材に種々の方法でコーティングして塗膜を形成した後、放射線を照射して硬化（反応性希釈剤の光重合反応）させることが好ましい。
このように塗膜に対して照射する放射線としては、例えば赤外線、可視光線、紫外線、遠紫外線、Ｘ線、電子線、α線、β線、γ線などを挙げることができる。また、第１の実施形態のように塗膜を構成する組成物中において放射線重合開始剤が含有されている場合には、当該放射線重合開始剤が感度を有する放射線を照射することが好ましい。放射線の照射量は、光源の種類、塗膜の膜厚などに応じて適宜設定することができる。
【００５６】
また、本発明の硬化性樹脂組成物中に、架橋性官能基含有共重合体および架橋性化合物が含有されている場合には、当該硬化性樹脂組成物の塗膜に対して放射線を照射するとともに、当該塗膜を加熱することが好ましい。これにより、架橋性官能基含有共重合体と架橋性化合物との反応（架橋反応）を促進することができる。
ここで、塗膜の加熱処理は、放射線照射の前後の何れに行ってもよく、放射線照射と同時に行ってもよい。また、塗膜の加熱処理手段としては、例えばオーブンなどを使用することができ、加熱条件としては、組成物中における架橋性官能基含有共重合体および架橋性化合物の含有量、基材の種類など応じて適宜設定することができる。
【００５７】
硬化膜が形成される基材としては、例えば、ポリカーボネート樹脂、アクリル樹脂、スチリル樹脂、アリレート樹脂、ノルボルネン系樹脂などのプラスチック基材；ガラス基材；金属基材；木材などが挙げられる。
また、硬化性樹脂組成物のコーティング法としては、例えば、スピンコーター、カーテンコーター、ロールコーターなどの各種塗布装置を用いる方法（組成物の好ましい粘度範囲：１〜１０，０００ｍＰａ・ｓ）；スクリーン印刷装置、グラビア印刷装置、オフセット印刷装置などの各種印刷装置を用いる方法（組成物の好ましい粘度範囲：１〜１００，０００ｍＰａ・ｓ）；ディッピング法（組成物の好ましい粘度範囲：１〜１，０００ｍＰａ・ｓ）などが挙げられる。
【００５８】
▲４▼ガラス転移点
硬化性樹脂組成物の硬化膜のガラス転移点を４０〜９０℃の範囲内の値とするのが好ましい。この理由は、ガラス転移点が４０℃未満となると、硬化膜の耐熱性や機械的強度が低下する場合があるためであり、一方、ガラス転移点が９０℃を超えると、基材に対する密着力が低下する場合が生じるためである。したがって、硬化膜の耐熱性や密着性とのバランスがより良好なことから、硬化膜のガラス転移点を５０〜８５℃の範囲内の値とするのがより好ましく、６０〜８０℃の範囲内の値とするのがさらに好ましい。
なお、硬化膜のガラス転移点は、示差走査型熱分析（ＤＳＣ）を行い、窒素中、一例として１０℃／分の昇温速度で加熱した場合に得られる比熱の変化点から算出することができる。
【００５９】
また、通常、硬化性樹脂組成物から得られた硬化膜において、一つのガラス転移点が得られるが（図４参照）、これは、本発明の硬化性樹脂組成物は、ヘキサフルオロプロピレン共重合体と、α−フルオロアクリレートモノマとの相溶性が良好なためと考えられる。すなわち、通常、ヘキサフルオロプロピレン共重合体、例えば、後述する実施例１で使用するポリマーＡ１のガラス転移点は０〜４０℃の範囲内である（図５参照）。一方、α−フルオロアクリレートモノマ、例えばトリフルオロエチルα−フルオロアクリレートモノマ単独の重合体のガラス転移点は、１００〜１２０℃の範囲内である。したがって、硬化膜のガラス転移点が一つであるということは、ヘキサフルオロプロピレン共重合体と、α−フルオロアクリレート重合体が均一に相溶し、化学的には結合していないものの、ガラス転移点が一つ現れるものと考えられる。
【００６０】
したがって、このようなガラス転移点は、下記式に則って容易に調整することができる。
１／Ｔ_p＝ｗ_H／Ｔ_H＋ｗ_F／Ｔ_F
Ｔ_p：硬化膜のガラス転移点（絶対温度）
Ｔ_H：ヘキサフルオロプロピレン共重合体のガラス転移点（絶対温度）
Ｔ_F：α−フルオロアクリレート重合体のガラス転移点（絶対温度）
ｗ_H：ヘキサフルオロプロピレン共重合体の重量分率（％）
ｗ_F：α−フルオロアクリレート重合体の重量分率（％）
【００６１】
ただし、硬化性樹脂組成物の添加成分の種類によっては、硬化膜において、二つ以上のガラス転移点が得られる場合がある。その場合には、高いガラス転移点の値を４０〜９０℃の範囲内の値となるように、混合比率やヘキサフルオロプロピレン共重合体やα−フルオロアクリレートモノマの種類を調整すれば良い。
【００６２】
［第２の実施形態］
第２の実施形態は、シロキサン結合を含むヘキサフルオロプロピレン共重合体と、α−フルオロアクリレートモノマと、当該α−フルオロアクリレートモノマと共重合可能なエチレン性不飽和化合物（以下、単にエチレン性不飽和化合物と称する場合がある。）と、放射線重合開始剤と、を含有する硬化性樹脂組成物である。
このようにα−フルオロアクリレートモノマ以外のエチレン性不飽和化合物を含むことにより、硬化性樹脂組成物の粘度や、得られる硬化膜の屈折率、密着力、機械的強度等の値を容易に調整することができる。
なお、以下の説明においては、第２の実施形態の特徴であるエチレン性不飽和化合物について中心に説明するものとし、その他の成分等については、第１の実施形態と同様とすることができる。
【００６３】
（１）種類
α−フルオロアクリレートモノマと共重合可能なエチレン性不飽和化合物は、光重合開始剤の存在下あるいは非存在下で活性エネルギー線が照射されることにより、あるいは熱重合開始剤の存在下で加熱されることにより付加重合する化合物である。
このようなエチレン性不飽和重合性化合物の具体例としては、エチレン、プロピレン、イソブテンなどのα−オレフィン類；スチレン、α−メチルスチレン、ｏ−メチルスチレン、ｍ−メチルスチレン、ｐ−メチルスチレン、ｐ−ｔｅｒｔ−ブチルスチレン、ジイソプロペニルベンゼン、ｏ−クロロスチレン、ｍ−クロロスチレン、ｐ−クロロスチレン、１，１−ジフェニルエチレン、ｐ−メトキシスチレン、Ｎ，Ｎ−ジメチル−ｐ−アミノスチレン、Ｎ，Ｎ−ジエチル−ｐ−アミノスチレン、ビニルピリジン、ビニルイミダゾールなどのビニル芳香族化合物；（メタ）アクリル酸、クロトン酸、マレイン酸、フマル酸、イタコン酸などのカルボキシル基含有化合物；メチル（メタ）アクリレート、エチル（メタ）アクリレート、プロピル（メタ）アクリレート、イソプロピル（メタ）アクリレート、ブチル（メタ）アクリレート、イソブチル（メタ）アクリレート、ｔｅｒｔ−ブチル（メタ）アクリレート、ペンチル（メタ）アクリレート、アミル（メタ）アクリレート、イソアミル（メタ）アクリレート、ヘキシル（メタ）アクリレート、ヘプチル（メタ）アクリレート、オクチル（メタ）アクリレート、イソオクチル（メタ）アクリレート、２−エチルヘキシル（メタ）アクリレート、ノニル（メタ）アクリレート、デシル（メタ）アクリレート、イソデシル（メタ）アクリレート、ウンデシル（メタ）アクリレート、ドデシル（メタ）アクリレート、ラウリル（メタ）アクリレート、ステアリル（メタ）アクリレート、イソステアリル（メタ）アクリレートなどのアルキル（メタ）アクリレート類；ヒドロキシエチル（メタ）アクリレート、ヒドロキシプロピル（メタ）アクリレート、ヒドロキシブチル（メタ）アクリレートなどのヒドロキシアルキル（メタ）アクリレート類；フェノキシエチル（メタ）アクリレート、２−ヒドロキシ−３−フェノキシプロピル（メタ）アクリレートなどのフェノキシアルキル（メタ）アクリレート類；メトキシエチル（メタ）アクリレート、エトキシエチル（メタ）アクリレート、プロポキシエチル（メタ）アクリレート、ブトキシエチル（メタ）アクリレート、メトキシブチル（メタ）アクリレートなどのアルコキシアルキル（メタ）アクリレート類；ポリエチレングリコールモノ（メタ）アクリレート、エトキシジエチレングリコール（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、フェノキシポリエチレングリコール（メタ）アクリレート、ノニルフェノキシポリエチレングリコール（メタ）アクリレートなどのポリエチレングリコール（メタ）アクリレート類；ポリプロピレングリコールモノ（メタ）アクリレート、メトキシポリプロピレングリコール（メタ）アクリレート、エトキシポリプロピレングリコール（メタ）アクリレート、ノニルフェノキシポリプロピレングリコール（メタ）アクリレートなどのポリプロピレングリコール（メタ）アクリレート類；シクロヘキシル（メタ）アクリレート、４−ブチルシクロヘキシル（メタ）アクリレート、ジシクロペンタニル（メタ）アクリレート、ジシクロペンテニル（メタ）アクリレート、ジシクロペンタジエニル（メタ）アクリレート、ボルニル（メタ）アクリレート、イソボルニル（メタ）アクリレート、トリシクロデカニル（メタ）アクリレートなどのシクロアルキル（メタ）アクリレート類；ベンジル（メタ）アクリレート、テトラヒドロフルフリル（メタ）アクリレート等の一種単独または二種以上の組み合わせを挙げられる。
【００６４】
（２）添加量
エチレン性不飽和化合物の添加量は特に制限されるものではないが、具体的に、α−フルオロアクリレートモノマ１００重量部に対して、かかる添加量を１〜１，０００重量部の範囲内の値とするのが好ましい。この理由は、エチレン性不飽和化合物の添加量が１重量部未満となると、添加効果が得られない場合があるためであり、一方、エチレン性不飽和化合物の添加量が１，０００重量部を超えると、硬化性樹脂組成物の相溶性が低下し、沈殿物が生じたり、硬化反応が不均一となる場合があるためである。
したがって、α−フルオロアクリレートモノマ１００重量部に対して、エチレン性不飽和化合物の添加量を２〜１００重量部の範囲内の値とするのがより好ましく、５〜５０重量部の範囲内の値とするのがさらに好ましい。
【００６５】
［第３の実施形態］
本発明の第３の実施形態は、第１および第２の実施形態で説明した硬化性樹脂組成物からなる反射防止膜である。なお、この反射防止膜は、基材上に設けられていれば良く、積層体として種々の変形例を採ることができる。以下、第３の実施形態の反射防止膜（積層体）を、図１〜図３を参照しつつ具体的に説明する。図１は、基材上１２に直接形成された反射防止膜１０を含む積層体１４の断面図であり、図２は、基材１２と反射防止膜１０との間にハードコート層１６を介在させた積層体１８の断面図である。また、図３は、下側から、基材１２と、ハードコート層１６と、第１の高屈折率層２０と、第１の反射防止膜２２と、第２の高屈折率層２４と、第２の反射防止膜２６とを順次に形成して構成した多層構造の積層体２８の断面図である。
【００６６】
図１に示す積層体１４の場合、第１および第２の実施形態で説明した硬化性樹脂組成物からなる反射防止膜１０を直接基材１２上に形成することができるので、構成が単層であってシンプルであり、しかも精度良く形成することができる。
また、図２に示す積層体１８のように、反射防止膜１０と基材１２との間に、ハードコート層１６を介在させると、反射防止膜１０の基材１２に対する密着力をより向上させることができ、また、ハードコート層１６の機械的特性に起因して積層体１８としての耐久性がより向上する。なお、ハードコート層１６は、例えば、ＳｉＯ₂、エポキシ系樹脂、アクリル系樹脂、メラミン系樹脂等の材料から構成するのが好ましく、さらには、その厚さを１〜５０μｍの範囲内の値とするのが好ましく、より好ましくは５〜１０μｍの範囲内の値とすることである。
【００６７】
また、図３に示す積層体２８のように、第１および第２の反射防止層２２、２６のほかに、比較的高い屈折率の値、例えば、１．５〜２．０（−）の範囲内の値を有する、厚さ５０〜２００ｎｍの第１および第２の高屈折率層２０、２４を、それぞれ第１および第２の反射防止層２２、２６と接して設けることも好ましい。このように本発明の反射防止層に接して高屈折率層２０、２４を設け、しかも複数層設けることにより、より優れた反射防止効果を得ることができる。
また、高屈折率層２０、２４を設ける場合、より優れた反射防止効果が得られることから、反射防止層２２、２６と、高屈折率層２０、２４との間の屈折率差を０．０５（−）以上の値とするのが好ましく、０．１〜０．５（−）の範囲内の値とするのがより好ましく、０．１５〜０．５（−）の範囲内の値とするのがさらに好ましい。
【００６８】
また、図２〜図３の積層体１８、２８に示すようにハードコート層１６や高屈折率層２０、２４、あるいはプライマー層（図示しない。）を設ける場合にも、その上に本発明の光硬化性組成物をコーティングした後に紫外線等を照射することにより、第１および第２の実施形態の硬化性樹脂組成物からなる反射防止膜１０、２２、２６を容易に形成することができる。その場合、反射防止効果の一端を担う高屈折率層２０、２４を含めて本発明の反射防止膜（反射防止層）と称する場合がある。
【００６９】
また、図１〜図３に示す積層体１４、１８、２８における基材１２の種類は、光が透過する際に反射防止効果が所望されるものであれば特に制限されるものではないが、例えば、ガラス、ポリカーボネート系樹脂、ポリエステル系樹脂またはアクリル系樹脂等を挙げることができる。基材１２がガラスの場合には、具体的な積層体として、カメラのレンズ部やテレビ（ＣＲＴ、ＬＣＤ）の画面表示部あるいは窓ガラス等が挙げられる。また、ポリカーボネート系樹脂、ポリエステル系樹脂またはアクリル系樹脂からなる基材１２の場合には、液晶表示装置におけるカラーフィルター等が挙げられる。
【００７０】
【実施例】
以下、本発明の実施の形態を実施例により、さらに詳細に説明する。但し、本発明は、その要旨を越えない限りこれらの実施例に何ら制約されるものではない。実施例中の部及び％は特にことわらない限り、それぞれ重量部及び重量％を示す。
【００７１】
［ヘキサフルオロプロピレン共重合体の合成］
（１）ポリマーＡ１
実施例１〜５および比較例１〜４を実施するにあたり、ポリマーＡ１としてのヘキサフルオロプロピレン共重合体の合成を行った。すなわち、内容積１．５リットルの電磁攪拌機付きステンレス製オートクレーブを窒素ガスで十分置換した後、表１に示すように、溶剤として酢酸エチル６００ｇ、ヘキサフルオロプロピレン（ＨＦＰ）と共重合可能な単量体として、パーフルオロ（プロピルビニルエーテル）（ＦＰＶＥ）３１．９ｇ、エチルビニルエーテル（ＥＶＥ）３０．２ｇ、及びヒドロキシエチルビニルエーテル（ＨＥＶＥ）１５．８ｇ、ノニオン性反応性乳化剤としてアデカリアソープＮＥ−３０（旭電化工業（株）製、一般式（３）におけるｎが９、ｍが１、ｓが３０である乳化剤）３０．０ｇ、アゾ基含有ポリジメチルシロキサンとしてＶＰＳ−１００１（和光純薬工業（株）製）１．２８ｇおよびジラウロイルパーオキサイド（ＬＰＯ）０．７５ｇをそれぞれ仕込み、ドライアイス−メタノールで−５０℃まで冷却した後、再度窒素ガスで十分置換した。
【００７２】
次いで、ヘキサフルオロプロピレン８６．４ｇをオートクレーブ内に導入した後、昇温を開始した。オートクレーブ内の温度が６０℃に達した時点での圧力は４．７ｋｇｆ／ｃｍ²を示した。その後、６０℃で２５時間攪拌下に反応を継続し、圧力が２．５ｋｇｆ／ｃｍ²に低下した時点でオートクレーブを水冷し、反応を停止させた。室温に達した後、未反応モノマを放出しオートクレーブを開放して、ポリマー溶液を得た。得られたポリマー溶液をメタノールに投入してポリマーを析出させ、メタノールにて洗浄し、さらに５０℃にて真空乾燥を行い１２９ｇのシロキサン結合を含むヘキサフルオロプロピレン共重合体（ポリマーＡ１）を得た。
【００７３】
得られたポリマーＡ１を濃度が０．５重量％溶液となるようにＴＨＦを用いて調整し、ゲルパーミエーションクロマトグラフィーによる分子量測定を行った。その結果、ポリスチレン換算による数平均分子量は７６，８００であった。さらにＤＳＣ分析によるガラス転移温度（Ｔｇ）、およびアリザリンコンプレクソン法によるフッ素含量をそれぞれ測定した。得られた結果を表１に示す。
なお、¹Ｈ−ＮＭＲ、¹³Ｃ−ＮＭＲの分析結果、元素分析結果並びにフッ素含量、水酸基価、さらには６００℃における焼成後の残重量から無機シリカ分を測定し、これらの測定からポリマーＡ１を構成する各モノマ成分の割合を決定した。その結果、ＨＦＰ／ＦＰＶＥ／ＥＶＥ／ＨＥＶＥ／ＮＥ−３０／（ＶＰＳ−１００１による構成成分）＝３９．７／９．７／３３．８／１３．６／１．１／２．１のモル比であることを確認した。
したがって、得られたポリマーＡ１は、ＶＰＳ−１００１に起因したポリシロキサン結合を確実に含んでいるとともに、共重合体中の各構成成分のうち、ＮＥ−３０についてのみ仕込み比と構成成分比との差が生じていることが判明した。
【００７４】
（２）ポリマーＡ２
比較例５を実施するにあたり、ポリマーＡ２としてのシロキサン結合を含まないヘキサフルオロプロピレン共重合体の合成を行った。すなわち、表１に示す組成において、ポリマーＡ１と同様にポリマーＡ２の合成を行った。得られたポリマーＡ２につき、ポリマーＡ１と同様に数平均分子量、フッ素含量、およびガラス転移温度をそれぞれ測定した。得られた結果を表１に示す。
また、ポリマーＡ２を構成する各モノマ成分の割合をポリマーＡ１と同様に決定した。その結果、ＨＦＰ／／ＥＶＥ＝４９．８／５０．２のモル比であることを確認した。
【００７５】
【表１】

【００７６】
なお、表１中の、略号は、下記内容を示している。
ＨＦＰ ：ヘキサフルオロプロピレン
ＦＰＶＥ ：パーフルオロ（プロピルビニルエーテル）
ＥＶＥ ：エチルビニルエーテル
ＨＥＶＥ ：ヒドロキシエチルビニルエーテル
ＶＰＳ-1001 ：アゾ基含有ポリジメチルシロキサン（和光純薬工業（株）製、数平均分子量が８０，０００、ポリシロキサン部分の分子量が約１０，０００）
ＮＥ−３０ ：ノニオン性反応性乳化剤ＮＥ−３０（旭電化工業（株）製）
ＬＰＯ ：ジラウロイルパーオキサイド
【００７７】
［α−フルオロアクリレートモノマの合成］
容量が２Ｌの容器内に収容した１Ｎ水酸化ナトリウム水溶液６００ｍＬと、テトラヒドロフラン６００ｍＬと、ｐ−メトキシフェノール０．０８ｇとからなる混合溶液に、メチル−α−フルオロアクリレート４２ｇを氷冷下に滴下後４時間撹拌して、反応させた。得られた反応液をオイルバス温度３０℃、減圧度１５０ｍｍＨｇの条件で濃縮した。その後、１Ｎ塩酸７００ｍＬをゆっくり加え、水層の液性を酸性にした後、塩化メチレン４００ｍＬで抽出して有機層を得た。次いで有機層を無水硫酸マグネシウムで乾燥した後、濾過した。得られたろ液を濃縮し、２８．８ｇのα−フルオロアクリル酸を白色固体として得た。
得られたα−フルオロアクリル酸２４ｇと、トリフルオロエタノール２６．５ｇと、ｐ−メトキシフェノール０．０１ｇと、塩化メチレン８４．０ｇとからなる混合溶液に、濃硫酸５２．１ｇを氷冷しながらゆっくり滴下した。滴下終了後、４０℃のオイルバスで加熱しながら撹拌した。２０時間後、オイルバスから反応器を取り出し、氷水しながら氷水５００ｍＬをゆっくり加えた。これを塩化メチレン３００ｍＬで３回抽出して有機層を得た。この有機層を飽和炭酸水素ナトリウム水溶液および食塩水でそれぞれ洗浄し、さらに硫酸マグネシウムで乾燥した後、濾過した。得られたろ液を濃縮し、減圧蒸留により精製を行いトリフルオロエチルα―フルオロアクリレートを２３ｇ得た。収率は８６％であった。
【００７８】
［実施例１］
表２に示すように、得られたシロキサン結合を含むヘキサフルオロプロピレン共重合体（Ａ１）１０．０ｇ、および放射線重合開始剤であるイルガキュア１８４ ３．０ｇを、それぞれトリフルオロエチルα―フルオロアクリレート９０ｇ中に溶解させた後、無溶剤でミキサを用いて、室温、２時間の条件で撹拌することにより硬化性樹脂組成物を得た。
得られた硬化性樹脂組成物（無溶剤）につき、（１）放射線硬化性および（２）塗布性を評価した。また、硬化性樹脂組成物から形成した硬化膜につき、（３）透明性および（４）屈折率を測定した。それぞれ得られた結果を表２に示す。
【００７９】
（１）放射線硬化性
２０×３０ｃｍ角に切断されたガラス板上に、バーコータにて硬化性樹脂組成物を塗工し、膜厚２００μｍの塗膜を形成した。次いで、窒素中、２５℃の条件で、それぞれ露光量が３００ｍＪ／ｃｍ²（照射時間３秒）、６００ｍＪ／ｃｍ²（照射時間６秒）、および９００ｍＪ／ｃｍ²（照射時間９秒）となるように、オーク製作所社製のコンベア式高圧水銀ランプ（２ｋＷ）を用いて紫外線を照射し、硬化膜を形成した。得られた硬化膜につき、指触で表面タックを測定し、以下の基準で硬化性樹脂組成物の放射線硬化性（光硬化性）を評価した。
◎：３００ｍＪ／ｃｍ²露光後、硬化膜の表面タックがない。
○：６００ｍＪ／ｃｍ²露光後、硬化膜の表面タックがない。
△：９００ｍＪ／ｃｍ²露光後、硬化膜の表面タックがない。
×：９００ｍＪ／ｃｍ²露光後、硬化膜の表面タックがある。
【００８０】
（２）塗布性
厚さ２ｍｍ、大きさ１０ｃｍ角のポリカーボネート板に、硬化性樹脂組成物をディップコータにより１μｍ厚に塗布し、高圧水銀ランプを用いて、露光量が９００ｍＪとなるように窒素中で露光して、硬化膜を得た。得られた硬化膜につき、塗布むらの有無を目視により下記基準にて判断し、塗布性を評価した。
○：塗布むらが全く無し。
△：塗布むらがわずかに有り。
×：塗布むらが有り。
【００８１】
（３）透明性
２０×３０ｃｍ角に切断されたガラス板上に、バーコータにて硬化性樹脂組成物を塗工し、膜厚２００μｍの塗膜を形成した。次いで、窒素下、２５℃の条件で、９００ｍＪ／ｃｍ²（照射時間９秒）となるように、上述したコンベア式高圧水銀ランプを用いて紫外線を照射し、硬化膜を形成した。得られた硬化膜につき、透明性を目視により下記基準にて評価した。
○：透明
△：やや白濁
×：白濁
【００８２】
（４）屈折率
２０×３０ｃｍ角に切断されたガラス板に、バーコータにて硬化性樹脂組成物を塗工し、膜厚２００μｍの塗膜を形成した。次いで、窒素下、２５℃の条件で、９００ｍＪ／ｃｍ²（照射時間９秒）となるように、上述したコンベア式高圧水銀ランプを用いて紫外線を照射し、硬化膜を形成した。得られた硬化膜につき、アッベ屈折率計を用いて測定温度２５℃の条件で屈折率を測定した。
【００８３】
［実施例２〜３］
表２に示すように、α−フルオロアクリレートの種類や添加量を代えて組成した以外は、実施例１と同様にして硬化性樹脂組成物（無溶剤）をそれぞれ製造した。そして、得られた硬化性樹脂組成物につき放射線硬化性や塗布性を評価し、さらに得られた硬化膜につき、透明性を実施例１と同様にして評価した。得られた結果を表２に示す。
【００８４】
［実施例４〜５］
表２に示すようにα−フルオロアクリレートの種類や添加量を代えるとともに、溶剤を添加して組成した以外は、実施例１と同様にして硬化性樹脂組成物（溶剤使用）をそれぞれ製造した。そして、得られた硬化性樹脂組成物につき放射線硬化性や塗布性を評価し、得られた硬化膜につき透明性や屈折率を実施例１と同様にして評価した。また、得られた硬化膜につき、さらに反射率および密着性を以下のように評価した。得られた結果を表２に示す。
【００８５】
（５）反射率
厚さ２ｍｍ、大きさ１０ｃｍ角のポリカーボネート板上に硬化性樹脂組成物をディップコータにより１μｍ厚にて塗布した後、高圧水銀ランプを用いて、窒素雰囲気下９００ｍＪ／ｃｍ²の露光を行い、反射防止膜を形成した。このポリカーボネート板の裏面に、艶消し黒スプレー（商品名：即乾アクリルラッカースプレー艶消しブラック、カンペアピオ（株）製）を塗布して乾燥させた。これを測定試料として、６０ｍｍφ積分球付き分光光度計（（株）日立製作所製 Ｕ−３４１０型）を用いて、波長５５０ｎｍにおける反射率の測定を行った。
【００８６】
（６）密着性の測定
厚さ２ｍｍ、大きさ１０ｃｍ角のポリカーボネート板上に硬化性樹脂組成物をディップコータにより１μｍ厚にて塗布した後、高圧水銀ランプにより窒素雰囲気下９００ｍＪ／ｃｍ²の露光を行い、反射防止膜を形成した。これを測定試料として、キムワイプ（十条キンバリー（株）製）を用いて硬化膜の表面を摩擦して、ポリカーボネート板に対する反射防止膜の密着性（耐擦傷性）を以下の基準で評価した。
○：塗膜の剥離や傷の発生がない。
×：塗膜の一部に剥離が生じ、あるいは塗膜面に筋状の傷が発生する。
【００８７】
［比較例１〜３］
表２に示すようにα−フルオロアクリレート以外のフルオロアクリレートを用いて組成した以外は、実施例１と同様にして硬化性樹脂組成物（無溶剤）をそれぞれ製造した。そして、得られた硬化性樹脂組成物につき放射線硬化性や塗布性を評価し、さらに得られた硬化膜につき、透明性、屈折率、および反射率を実施例１と同様にして評価した。得られた結果を表２に示す。
【００８８】
［比較例４］
表２に示すようにα−フルオロアクリレート以外のフルオロアクリレートを用いて組成した以外は、実施例４と同様にして硬化性樹脂組成物（溶剤使用）をそれぞれ製造した。そして、得られた硬化性樹脂組成物につき放射線硬化性や塗布性を評価し、さらに得られた硬化膜につき、透明性、屈折率、および反射率を実施例１と同様にして評価した。得られた結果を表２に示す。
【００８９】
【表２】

【００９０】
なお、表２中の略号は、下記内容を示している。また、表２中、成分（Ａ）はシロキサン結合を含むヘキサフルオロプロピレン共重合体を表し、成分（Ｂ）はα−フルオロアクリレートを表し、成分（Ｃ）はα−フルオロアクリレート以外のフルオロアクリレートを表し、成分（Ｄ）は重合開始剤を表し、さらに成分（Ｅ）は溶剤を表している。
ＡＲＦ３Ｆ ：トリフルオロエチルα−フルオロアクリレート
ＡＲＦ４Ｆ ：2,2,3,3−テトラフルオロプロピルα−フルオロアクリレート
Ｉｒｇ.184 ：１−ヒドロキシ−シクロヘキシル−フェニル−ケトン
（チバスペシャルティケミカルズ（株）製）
３Ｆ ：トリフルオロエチルアクリレート
８Ｆ ：オクタフルオロペンチルアクリレート
ＮＰ−Ａ ：ネオペンチルグリコールジアクリレート（共栄社油脂化学工業（株）製
ＭＩＢＫ ：メチルイソブチルケトン
【００９１】
【発明の効果】
本発明の硬化性樹脂組成物によれば、シロキサン結合を有するヘキサフルオロプロピレン共重合体と、α−フルオロアクリレートモノマとの組み合わせにより、溶剤を使用しなくとも特異的に良好な相溶性が得られ、また、優れた放射線硬化性や塗布性を得ることができるようになった。
したがって、本発明の硬化性樹脂組成物は、基材表面における反射防止膜や防汚膜などとして使用することができるほか、接着剤、封止剤、あるいは光ファイバークラッド材などとしても好適に使用することができる。
【００９２】
また、本発明の硬化膜によれば、基材に対して優れた密着性を有すると共に、低い屈折率ならびに可視光に対する優れた透明性を得ることができるようになった。したがって、本発明の硬化膜は、反射防止膜や防汚膜などとして使用した場合に、優れた耐久性や光学特性を発揮することができる。
【００９３】
また、本発明の反射防止膜によれば、上述した硬化膜としての特性を得ることができるばかりか、低い反射率、例えば、２％以下の値が得られるようになった。
さらに、本発明の反射防止膜は、架橋しているため、機械的強度が高く、耐擦傷性および表面摺動性（耐摩耗性）を発現させるために好適な硬度を有しており、さらには、シロキサン結合やフッ素基を有しているため、耐候性にも富んでいることが期待される。
【図面の簡単な説明】
【図１】本発明の反射防止膜を含む積層体の断面を示す図である（その１）。
【図２】本発明の反射防止膜を含む積層体の断面を示す図である（その２）。
【図３】本発明の反射防止膜を含む積層体の断面を示す図である（その３）。
【図４】シロキサン結合を含むヘキサフルオロプロピレン共重合体のＤＳＣ測定チャートである。
【図５】本発明の硬化性樹脂組成物から得られた硬化膜のＤＳＣ測定チャートである。
【符号の説明】
１０、２２、２６ 反射防止膜
１２ 基材
１４、１８、２８ 積層体
１６ ハードコート層
２０、２２ 高屈折率層[0001]
[Field of the Invention]
The present invention relates to an active energy ray-curable resin composition (sometimes simply referred to as a curable resin composition) excellent in radiation curability and coating properties, a cured film having transparency and a low refractive index, and curability. The present invention relates to an antireflection film having a low reflectance obtained by curing a resin composition on a substrate.
[0002]
[Prior art]
Fluorine-based compounds and fluorine-based resin compositions use a low refractive index to make use of materials for antireflection films such as optical lenses, films, and CRT glass, cladding materials for optical fibers, and optical fibers. It is used as an optical adhesive for optical lenses and the like. Fluorine compounds are also used as antifouling coating materials because they have water and oil repellency.
[0003]
One such fluororesin composition is disclosed in JP-A No. 64-14221. This fluorine-based composition comprises (1) compounds 10 to 90 obtained by reacting a fluorine-containing copolymer comprising an α-fluoroacrylate monomer and an acrylate monomer having a glycidyl group with a carboxyl group-containing ethylenically unsaturated monomer. (2) 10 to 90 parts by weight of an acrylic monomer for viscosity adjustment, and (3) 0.05 to 20 parts by weight of a photopolymerization initiator.
[0004]
Japanese Patent Application Laid-Open No. Sho 62-250047 discloses a fluorine-containing polymer composed of an α-fluoroacrylate monomer and other acrylate monomers, an α-fluoroacrylate monomer, and other acrylic monomers. -Based resin compositions are disclosed.
Further, JP-A-62-199643 discloses fluorine comprising a fluorine-containing polymer having a fluorine atom of 30% by weight or more, an α-fluoroacrylate monomer, another acrylic monomer, and a polyfunctional monomer. -Based resin compositions are disclosed.
[0005]
[Problems to be solved by the invention]
However, the fluorine-based resin compositions disclosed in any patent publications have poor compatibility between the α-fluoroacrylate monomer and the fluoropolymer, and are excellent in cured films having a uniform thickness and transparency. It was difficult to form a cured film. In addition, the fluorine-based resin compositions disclosed in any of the patent publications have poor surface slidability in a cured film after curing and adhesion to a substrate, particularly glass or polycarbonate. It was difficult to use it as a cladding material.
[0006]
On the other hand, Japanese Patent Application Laid-Open No. 62-250047 and the like have also proposed the addition of a silane coupling agent or a low molecular weight siloxane compound in a fluororesin composition for the purpose of improving the adhesion with a substrate. . However, since the silane coupling agent and the like are poorly compatible with the fluorine-based copolymer and α-fluoroacrylate monomer, it becomes more difficult to obtain a uniform cured film, or the silane coupling agent is removed from the cured film. There was a problem that ring agents and the like easily bleed.
Furthermore, as described in JP-A-62-250047 and the like, conventionally, silicone resins are easily peeled off when used in oil, have a short pot life, and have a high refractive index. Problems such as limited range were pointed out.
[0007]
Therefore, the present inventor has intensively studied the above problems, and shows that the hexafluoropropylene copolymer containing a siloxane bond and the α-fluoroacrylate monomer have a particularly excellent compatibility even in the absence of a solvent. And it discovered that the adhesive force with respect to a base material improved by combining in this way. Further, since the silicone resin is not used alone, it has been found that problems such as pot life in the conventional silicone resin do not occur while taking advantage of the characteristics of the siloxane bond (silicone).
That is, an object of the present invention is to provide an active energy ray-curable resin composition that exhibits excellent coatability and compatibility even without a solvent.
Another object of the present invention is to provide a cured film (antireflection film) comprising a curable resin composition, which is excellent in transparency and adhesion, and has a low refractive index and reflectance. .
[0008]
[Means for Solving the Problems]
The present invention is an active energy ray-curable resin composition comprising a hexafluoropropylene copolymer containing a siloxane bond and an α-fluoroacrylate monomer.
By comprising in this way, even if it is solventless, the outstanding compatibility and applicability | paintability are obtained, and when forming a cured film, the outstanding adhesiveness and transparency can be expressed stably. . Moreover, since the siloxane bond is introduced into the hexafluoropropylene copolymer, problems such as a decrease in pot life and bleeding due to the siloxane compound can be effectively avoided.
[0009]
Moreover, when comprising the curable resin composition of this invention, it is preferable to contain the alpha-fluoro acrylate monomer represented by following General formula (1).
CH₂= CF-COOR_f      (1)
[In general formula (1), R_fIs a hydrocarbon group having at least one fluorine atom which may contain oxygen atoms. ]
With such a monofunctional monomer, better compatibility with a hexafluoropropylene copolymer containing a siloxane bond is obtained, and when cured, a cured film with excellent transparency is formed. be able to.
[0010]
Further, in constituting the curable resin composition of the present invention, the hexafluoropropylene copolymer containing a siloxane bond is a copolymer obtained using an azo group-containing polysiloxane compound as a radical generator. Is preferred.
By comprising in this way, the hexafluoropropylene copolymer containing a siloxane bond can be obtained easily and in a short time, and an inexpensive curable resin composition can be provided. Further, the siloxane bond introduced in this way is blocked, and can exhibit more excellent surface slidability in the cured film.
[0011]
In constituting the curable resin composition of the present invention, the hexafluoropropylene copolymer containing a siloxane bond is preferably a copolymer obtained using a nonionic reactive emulsifier.
By comprising in this way, the compatibility of the hexafluoropropylene copolymer containing a siloxane bond and the α-fluoroacrylate monomer can be further improved.
[0012]
Further, in constituting the curable resin composition of the present invention, the hexafluoropropylene unit amount in 100 mol% of the hexafluoropropylene copolymer containing a siloxane bond may be set to a value within the range of 20 to 70 mol%. preferable.
By comprising in this way, the outstanding water repellency and low refractive index property are obtained, and (alpha) -fluoro acrylate monomer can be mixed more uniformly with respect to a hexafluoropropylene copolymer.
[0013]
Further, in constituting the curable resin composition of the present invention, the amount of α-fluoroacrylate monomer added is in the range of 1 to 10,000 parts by weight with respect to 100 parts by weight of the hexafluoropropylene copolymer containing a siloxane bond. It is preferable to set the value within the range.
By comprising in this way, (alpha) -fluoro acrylate monomer can be mixed more uniformly with respect to the hexafluoropropylene copolymer containing a siloxane bond.
[0014]
Another aspect of the present invention is a cured film obtained by curing any of the curable resin compositions described above with active energy rays, or an antireflection film obtained by curing with active energy rays on a substrate. .
By comprising in this way, the anti-reflective film etc. which have the outstanding anti-reflective property which has the outstanding adhesiveness with respect to a base material, the outstanding surface slidability, and also adjusts a refractive index easily are obtained. Can do.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments relating to the active energy ray-curable resin composition and the antireflection film of the present invention will be specifically described.
[0016]
[First Embodiment]
In the first embodiment, a hexafluoropropylene copolymer containing a siloxane bond (hereinafter sometimes simply referred to as a hexafluoropropylene copolymer) and an α-fluoroacrylate represented by the following general formula (1): It is an active energy ray-curable resin composition containing a monomer and a radiation polymerization initiator. This hexafluoropropylene copolymer is a copolymer obtained using an azo group-containing polysiloxane compound and a nonionic reactive emulsifier.
CH₂= CF-COOR_f      (1)
[In general formula (1), R_fIs a hydrocarbon group having at least one fluorine atom which may contain oxygen atoms. ]
[0017]
(1) Hexafluoropropylene copolymer containing a siloxane bond
A hexafluoropropylene copolymer containing a siloxane bond is obtained by copolymerizing or reacting hexafluoropropylene, a monomer copolymerizable with the hexafluoropropylene (sometimes simply referred to as a copolymerized monomer), and a siloxane component. Can be obtained.
Here, in addition to hexafluoropropylene, a copolymerized monomer is used because it is difficult to polymerize with hexafluoropropylene alone, and also for adjusting the fluorine content in the copolymer. . Moreover, the siloxane component in 1st Embodiment is a part of azo group containing polysiloxane compound as a radical polymerization initiator.
[0018]
(1) Monomer copolymerizable with hexafluoropropylene
Examples of copolymerizable monomers include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl vinyl ether, 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl. Hydroxyl group-containing vinyl ethers such as vinyl ether;
Hydroxyl group-containing allyl ethers such as 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether, glycerol monoallyl ether;
Allyl alcohol; methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl vinyl ether, Alkyl vinyl ethers or cycloalkyl vinyl ethers such as 2-ethylhexyl vinyl ether and cyclohexyl vinyl ether;
Perfluoro (alkyl vinyl ether) such as perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), perfluoro (propyl vinyl ether), perfluoro (butyl vinyl ether), perfluoro (isobutyl vinyl ether), perfluoro (propoxypropyl vinyl ether) Or perfluoro (alkoxyalkyl vinyl ethers), or CH₂= CH-O-R_g(R_gRepresents an alkyl group or an alkoxyalkyl group containing a fluorine atom) (fluoroalkyl) vinyl ether or (fluoroalkoxyalkyl) vinyl ether represented by
Fluoroolefins such as vinylidene fluoride, chlorotrifluoroethylene, 3,3,3-trifluoropropylene, tetrafluoroethylene;
Carboxylic acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl caproate, vinyl versatate, vinyl stearate;
Α-olefins such as ethylene, propylene and isobutene;
2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2- (perfluoro Fluorine-containing (meth) acrylic esters such as hexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate;
Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (n-propoxy) ) (Meth) acrylic esters such as ethyl (meth) acrylate;
Carboxyl group or epoxy group-containing vinyl monomers such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, allyl glycidyl ether, glycidyl (meth) acrylate;
One type of N-vinyl monomer such as N-vinylpyrrolidone and N-vinylcaprolactam may be used alone or in combination of two or more types.
[0019]
Of these copolymerized monomers, it is preferable to use hydroxyl group-containing vinyl ethers, alkyl vinyl ethers, cycloalkyl vinyl ethers, and carboxylic acid vinyl esters in order to further increase the yield of the hexafluoropropylene copolymer. . Low molecular weight monomers such as methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, vinyl acetate, vinyl propionate, vinyl butyrate and vinyl pivalate are used to increase the fluorine content of the hexafluoropropylene copolymer. It is preferable. Furthermore, in order to increase the hardness of the hexafluoropropylene copolymer, it is preferable to use a branched monomer such as isopropyl vinyl ether, tert-butyl vinyl ether, or vinyl pivalate.
[0020]
Further, when the amount of hexafluoropropylene is less than 53% by weight, the copolymerized monomer has a fluorine content such as perfluoro (alkyl vinyl ether) or perfluoro (alkoxyalkyl vinyl ether) in order to increase the fluorine content. It is preferable to copolymerize a fluorine-containing monomer having a large size.
Further, in order to improve the adhesion to the substrate, a reactive group-containing monomer (hereinafter referred to as a reactive group-containing monomer) containing at least one reactive group selected from a hydroxyl group, an epoxy group, an amino group, and a carboxyl group. Is preferably used.
[0021]
(2) Amount of copolymerized monomer
As the ratio of each monomer constituting the hexafluoropropylene copolymer, the hexafluoropropylene unit is within the range of 20 to 70 mol% when the total amount of the monomers when forming the copolymer is 100 mol%. It is preferable to set it as the value of this, and it is more preferable to set it as the value within the range of 25-55 mol%. In other words, the copolymerized monomer unit is preferably set to a value in the range of 30 to 70 mol%, and more preferably set to a value in the range of 25 to 55 mol% mol%.
The reason for this is that when the hexafluoropropylene content is less than 20 mol%, the adhesion and water repellency of the cured film may decrease, whereas when it exceeds 70 mol%, the transparency of the cured film is reduced. This is because there is a case where mechanical strength is lowered or mechanical strength is lowered.
[0022]
In addition, when mix | blending a reactive group containing monomer, when the compounding quantity makes the whole monomer quantity at the time of producing a copolymer 100 mol%, the value in the range of 1-20 mol% and It is preferable to set it to a value within the range of 3 to 15 mol%.
The reason for this is that when the reactive group-containing monomer is less than 1 mol%, the strength of the coating film to be formed and the adhesion to the substrate may be reduced. This is because the storage stability of may decrease.
[0023]
(3) Fluorine content
The fluorine content in the hexafluoropropylene copolymer is preferably 40% by weight or more, and more preferably 45% by weight or more. This is because when the fluorine content is less than 40% by weight, the refractive index increases, and the characteristics as an antireflection film or a clad material may not be exhibited.
The fluorine content in the hexafluoropropylene copolymer can be measured using the alizarin complex method.
[0024]
(4) Number average molecular weight
The number average molecular weight of the hexafluoropropylene copolymer is preferably set to a value in the range of 5,000 to 2,000,000. The reason for this is that if the number average molecular weight is less than 5,000, the mechanical strength of the resulting hexafluoropropylene copolymer may decrease, whereas if it exceeds 2,000,000, α- This is because the compatibility with the fluoroacrylate monomer may decrease. Therefore, it is more preferable to set the number average molecular weight of the hexafluoropropylene copolymer to a value within the range of 30,000 to 1,000,000.
[0025]
(5) Polymerization method
The polymerization method of the hexafluoropropylene copolymer is not particularly limited. For example, an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, or a solution polymerization method can be employed in the presence of a radical polymerization initiator. Further, this polymerization method can be appropriately selected according to the purpose, such as batch method, semi-continuous method or continuous method.
[0026]
(Azo group-containing polysiloxane compound)
In addition, the radical polymerization initiator used in such a polymerization method is not particularly limited, but in the first embodiment, in order to easily introduce a siloxane bond into the hexafluoropropylene copolymer, an azo group is used. A group-containing polysiloxane compound is used. In addition, by using such a radical polymerization initiator, a block copolymer that regularly includes units composed of hexafluoropropylene and a copolymer component and polysiloxane units can be easily prepared. For example, when an azo group-containing polysiloxane compound in which polydimethylsiloxane is linked by an azo group is used, a block copolymer of a hexafluoropropylene copolymer and polydimethylsiloxane can be obtained.
[0027]
Examples of such commercially available azo group-containing polysiloxane compounds include VPS1001 and VPS0501 in which polydimethylsiloxane represented by the general formula (2) is linked by an azo group (both manufactured by Wako Pure Chemical Industries, Ltd.) Etc.
[0028]
[Chemical 1]

[0029]
[In general formula (2), y is an integer of 60-150, and z is an integer of 6-10. ]
[0030]
Moreover, it is preferable to make the usage-amount of an azo group containing polysiloxane compound into the value within the range of 0.01-20 weight part with respect to 100 weight part of total amounts of hexafluoropropylene and its copolymerization monomer. This is because when the amount of the azo group-containing polysiloxane compound is less than 0.01 parts by weight, a hexafluoropropylene copolymer may not be obtained. This is because if the amount exceeds 20 parts by weight, the molecular weight of the resulting hexafluoropropylene copolymer may be significantly reduced.
Therefore, the amount of the azo group-containing polysiloxane compound used is within the range of 0.1 to 15 parts by weight with respect to 100 parts by weight of the total amount of hexafluoropropylene and its copolymerized monomer from the viewpoint of such polymerizability. More preferably, the value is more preferably in the range of 1 to 10 parts by weight.
[0031]
(Other radical polymerization initiators)
Since the polymerization rate is controlled, radical polymerization initiators other than azo group-containing polysiloxane compounds, such as diacyl peroxides, ketone peroxides, hydroperoxides, dialkyl peroxides, peroxyesters, azo A single compound or a combination of two or more of a system compound and a persulfate may be mentioned.
Moreover, it is also preferable to use together inorganic reducing agents, such as sodium hydrogen sulfite and sodium pyrosulfite, and organic reducing agents, such as cobalt naphthenate and dimethylaniline, as needed. By using in combination in this way, a rapid radical reaction can be caused.
Furthermore, the iodine-containing fluorine compound can be suitably used alone or in combination with the organic peroxide, azo compound or persulfate described above.
[0032]
(Nonionic reactive emulsifier)
In the first embodiment, a nonionic reactive emulsifier is used in the polymerization of the hexafluoropropylene copolymer. This is because the compatibility between the hexafluoropropylene copolymer containing a siloxane bond and the α-fluoroacrylate monomer is further improved.
Examples of such a nonionic reactive emulsifier include an emulsifier represented by the following general formula (3). Examples of commercially available nonionic reactive emulsifiers include Adekari Soap NE-30 (Asahi Denka Kogyo Co., Ltd.). Etc.).
[0033]
[Chemical 2]

[0034]
[In general formula (3), n is an integer of 1-20, m is an integer of 1-10, u is an integer of 10-100. ]
[0035]
In addition, it is preferable to make the usage-amount of a nonionic reactive emulsifier into the value within the range of 0.01-15 weight part with respect to 100 weight part of total amounts of hexafluoropropylene and its copolymerization monomer. The reason for this is that when the amount of the nonionic reactive emulsifier used is less than 0.01 parts by weight, the effect of addition may not be obtained, while the amount of the nonionic reactive emulsifier used is 15 parts by weight. This is because, if it exceeds, the obtained fluorine-containing copolymer may be subjected to a general reprecipitation treatment and cannot be purified. That is, if a large amount of nonionic reactive emulsifier is present, it may be difficult to solidify the fluorinated copolymer.
Therefore, the amount of the nonionic reactive emulsifier used is more preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of hexafluoropropylene and its copolymerized monomer. More preferably, the value is in the range of ˜5 parts by weight.
[0036]
(2) α-Fluoroacrylate monomer
▲ 1 ▼ Type
The α-fluoroacrylate monomer used in the present invention is not particularly limited as long as it is an acrylate having a fluorine atom at the α position, and a wide variety can be used. The α-fluoroacrylate monomer can be specifically compatible with the hexafluoropropylene copolymer. In addition, α-fluoroacrylate monomer is capable of rapid radiation polymerization even when mixed with a hexafluoropropylene copolymer, and therefore exhibits a high glass transition point and excellent mechanical properties upon polymerization. Can do.
Such an α-fluoroacrylate monomer can be obtained, for example, by the production method (methyl esterification reaction and transesterification reaction) disclosed in JP-A-50-52019.
[0037]
Further, a preferable α-fluoroacrylate monomer is preferably a compound represented by the general formula (1) described above.
More specifically, trifluoroethyl α-fluoroacrylate, 2,2,3,3-tetrafluoropropyl α-fluoroacrylate, hexafluoroisopropyl α-fluoroacrylate, octafluoropentyl α-fluoroacrylate, heptadecafluorodecyl One type of α-fluoroacrylate or a combination of two or more types can be used.
[0038]
Further, as α-fluoroacrylate monomer, R in the general formula (1)_fOxygen atoms intervened in the main chain, such as CH₂= CF-COOCF₂C (CF_Three) FOCF (CF_Three)_ThreeA compound represented by the structural formula is also preferable. R like this_fThis is because an α-fluoroacrylate monomer in which an oxygen atom intervenes in the main chain is relatively easy to synthesize and is easily available.
[0039]
The α-fluoroacrylate monomer is preferably a divinyl compound represented by the following general formulas (4) and (5). This is because the mechanical strength of the obtained cured film can be further increased by using such a divinyl compound.
[0040]
CH₂= CFCOO (CH₂)_x(CF₂)_y(CH₂)_xOCOF = CH₂    (4)
[In General Formula (4), x is an integer of 1-2, and y is an integer of 4-12. ]
[0041]
[Chemical 3]

[0042]
[In the general formula (5), m and n are integers from 0 to 10 (but not simultaneously 0), R is hydrogen or an alkyl group having 1 to 10 carbon atoms, R_fIs the same as in the general formula (1). ]
[0043]
(2) Amount added
Moreover, it is preferable to make the addition amount of (alpha) -fluoro acrylate monomer into the value within the range of 1-10,000 weight part with respect to 100 weight part of hexafluoropropylene copolymers. The reason for this is that when the addition amount of the α-fluoroacrylate monomer is less than 1 part by weight, the curability may be remarkably lowered, while the addition amount of the α-fluoroacrylate monomer is less than 10,000 parts by weight. If it exceeds, the viscosity of the composition will be low, so that it may be difficult to form a desired film thickness, and the flexibility and slidability of the cured film may be reduced.
Therefore, since the balance between the curability and the properties of the cured film becomes better, the addition amount of the α-fluoroacrylate monomer is in the range of 10 to 5,000 parts by weight with respect to 100 parts by weight of the hexafluoropropylene copolymer. It is more preferable to set the value within the range, and it is more preferable to set the value within the range of 100 to 1,000 parts by weight.
[0044]
(3) Radiation polymerization initiator
The curable resin composition can contain a radiation polymerization initiator and can be efficiently cured by irradiation with an active energy ray such as ultraviolet rays. That is, the radiation polymerization initiator is a compound that accelerates the polymerization reaction of the α-fluoroacrylate monomer by receiving active energy rays.
[0045]
Specific examples of such a radiation polymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2,2′-dimethoxy-2-phenylacetophenone, xanthone, fluorene, fluorenone, benzaldehyde, anthraquinone, triphenylamine, carbazole, 3-methyl. Acetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, Michler's ketone, benzoylpropyl ether, benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy- 2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-benzyl-2-dimethyl 1 type of amino-1- (4-morpholinophenyl) butan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methylpropan-1-one alone or 2 A combination of more than one species can be mentioned. Of these, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 1-hydroxycyclohexyl phenyl ketone are more preferred.
[0046]
Also, the amount of radiation polymerization initiator used is not particularly limited. For example, when the total amount of the hexafluoro copolymer and the α-fluoroacrylate monomer is 100 parts by weight, 0.1 to 20 A value within the range of parts by weight is preferred. The reason for this is that when the amount of the radiation polymerization initiator used is less than 0.1 parts by weight, the reaction rate of the α-fluoroacrylate monomer may be slow, or it may be easily influenced by oxygen present in the surroundings. Because. On the other hand, when the amount of the radiation polymerization initiator used exceeds 20 parts by weight, the molecular weight of the α-fluoroacrylate monomer is lowered, and the mechanical strength and heat resistance of the resulting cured film may be lowered. Therefore, since the balance between the reaction rate of the α-fluoroacrylate monomer and the properties of the cured film is improved, the amount of the radiation polymerization initiator used is set to a value within the range of 0.5 to 10 parts by weight. Is more preferable.
[0047]
(4) Additive
The composition of the present invention preferably contains various additives for the purpose of improving the coating properties of the composition, the photosensitivity of the composition, and various properties of the cured film of the composition. Examples of such additives include polymer materials other than hexafluoropropylene copolymers, colorants such as pigments and dyes, fillers, antioxidants, ultraviolet absorbers, light stabilizers, anti-aging agents, and silane cups. Examples thereof include a ring agent, a crosslinkable compound, a surfactant, a polymerization inhibitor, and a solvent.
[0048]
More specifically, preferred polymer materials include acrylic resins such as polymethyl (meth) acrylate, epoxy resins, novolac resins, and resole resins.
Preferred examples of the UV absorber include salicylic acid UV absorbers, benzophenone UV absorbers, benzotriazole UV absorbers, and cyanoacrylate UV absorbers.
Preferred anti-aging agents include di-tert-butylphenol, pyrogallol, benzoquinone, hydroquinone, n-butylphenol, hydroquinone monopropyl ether, 4,4 ′-[1- [4- (1- (4-hydroxyphenyl) -1 -Methylethyl) phenyl] ethylidene] diphenol, 1,1,3-tris (2,5-dimethyl-4-hydroxyphenyl) -3-phenylpropane, diphenylamines, phenylenediamines, phenothiazine, mercaptobenzimidazole, etc. Can be mentioned.
[0049]
Preferred silane coupling agents include γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane.
In addition, when the total amount of the hexafluoro copolymer and the α-fluoroacrylate monomer is 100 parts by weight, the additive amount described above is set to a value within the range of 0.01 to 5 parts by weight. Is preferable, and it is more preferable to set the value within the range of 0.01 to 3 parts by weight. The reason for this is that when the additive amount of various additives is less than 0.01 parts by weight, the effect of addition may not be manifested. On the other hand, when the additive amount of various additives exceeds 5 parts by weight, it is obtained. This is because the photocurability of the curable resin composition may be lowered.
[0050]
Examples of the crosslinkable compounds include amino resins such as melamine, polyisocyanates, polybasic acids, polybasic acid anhydrides, polyamines, polyols, epoxy compounds, epoxy resins, and hydroxyl group-containing compounds (eg, pentaerythritol, polyphenols, glycols) It is preferable to add one or a combination of two or more of compounds having a group capable of reacting with the crosslinkable functional group constituting the polymer component. It is also preferable to add a reaction catalyst for promoting the reaction (crosslinking reaction) between the crosslinkable functional group of the polymer component and the crosslinkable compound in the composition.
In addition, as the addition amount of the crosslinkable compound, the effects of the present invention are not impaired, and a suitable crosslinked structure can be introduced into the cured film formed from the curable resin composition. It is preferable to set it as the value within the range of 0.5-1.0 equivalent per 1 functional functional group, and it is more preferable to set it as the value within the range of 0.7-1.0 equivalent.
[0051]
The surfactant is preferably added for the purpose of improving the coating properties and antistatic properties of the curable resin composition. Examples of such surfactants include known surfactants such as anionic surfactants, cationic surfactants, and nonionic surfactants.
In addition, the addition amount of the surfactant is set to a value within the range of 0.01 to 5 parts by weight when the total amount of the hexafluoropropylene copolymer and the α-fluoroacrylate monomer is 100 parts by weight. Is preferable, and it is more preferable to set the value within the range of 0.01 to 3 parts by weight. The reason for this is that when the addition amount of the surfactant is less than 0.01 parts by weight, the effect of addition may not be manifested. On the other hand, when the addition amount of the surfactant exceeds 5 parts by weight, it is obtained. This is because the water resistance and adhesion of the curable resin composition may be impaired.
[0052]
Moreover, it is preferable to add a solvent for the purpose of adjusting the viscosity in a curable resin composition in a preferable range, and improving applicability | paintability. Examples of such solvents include esters such as ethyl acetate, butyl acetate, isopropyl acetate, isobutyl acetate, and cellosolve; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; cyclic ethers such as tetrahydrofuran and dioxane; N Amides such as N, N-dimethylformamide and N, N-dimethylacetamide; aromatic hydrocarbons such as toluene and xylene, and alcohols; aliphatic hydrocarbons and the like can be used together with these. preferable.
[0053]
(5) Curable resin composition
(1) Preparation method
The curable resin composition of the present invention can be prepared by mixing a hexafluoropropylene copolymer and an α-fluoroacrylate monomer at room temperature or under heating conditions. Specifically, it can be easily prepared using a mixer such as a mixer, a ball mill, or a three roll.
[0054]
(2) Viscosity
The viscosity of the curable resin composition is set appropriately depending on the type (monomer composition) and molecular weight of the hexafluoropropylene copolymer, the use ratio of the hexafluoropropylene copolymer, and the viscosity modifier (including the monomer component). Thus, it can be adjusted to a value within a preferable range according to the coating method to be employed. For example, it is preferable to adjust the viscosity of the curable resin composition to a value within the range of 10 to 100,000 mPa · s (measurement temperature 25 ° C.).
[0055]
(3) Curing method
The curing method of the curable resin composition is not particularly limited. For example, after coating the substrate by various methods to form a coating film, the coating is formed by irradiation with radiation (reactive diluent light). Polymerization reaction).
Examples of the radiation applied to the coating film include infrared rays, visible rays, ultraviolet rays, far ultraviolet rays, X-rays, electron beams, α rays, β rays, and γ rays. Moreover, when the radiation polymerization initiator contains in the composition which comprises a coating film like 1st Embodiment, it is preferable to irradiate the radiation which the said radiation polymerization initiator has sensitivity. The dose of radiation can be appropriately set according to the type of light source, the film thickness of the coating film, and the like.
[0056]
When the curable resin composition of the present invention contains a crosslinkable functional group-containing copolymer and a crosslinkable compound, the coating film of the curable resin composition is irradiated with radiation. At the same time, it is preferable to heat the coating film. Thereby, reaction (crosslinking reaction) with a crosslinkable functional group containing copolymer and a crosslinkable compound can be accelerated | stimulated.
Here, the heat treatment of the coating film may be performed before or after the radiation irradiation, or may be performed simultaneously with the radiation irradiation. Moreover, as a heat-treatment means of a coating film, oven etc. can be used, for example, As heating conditions, content of the crosslinkable functional group containing copolymer and crosslinkable compound in a composition, the kind of base material It can set suitably according to.
[0057]
Examples of the substrate on which the cured film is formed include plastic substrates such as polycarbonate resin, acrylic resin, styryl resin, arylate resin, norbornene resin; glass substrate; metal substrate; wood and the like.
Moreover, as a coating method of the curable resin composition, for example, a method using various coating apparatuses such as a spin coater, a curtain coater, and a roll coater (preferable viscosity range of the composition: 1 to 10,000 mPa · s); screen printing Method using various printing apparatuses such as an apparatus, a gravure printing apparatus, an offset printing apparatus (preferred viscosity range of composition: 1 to 100,000 mPa · s); dipping method (preferred viscosity range of composition: 1 to 1,000 mPa · s) s).
[0058]
(4) Glass transition point
The glass transition point of the cured film of the curable resin composition is preferably set to a value in the range of 40 to 90 ° C. This is because when the glass transition point is less than 40 ° C., the heat resistance and mechanical strength of the cured film may be lowered. On the other hand, when the glass transition point exceeds 90 ° C., the adhesion to the substrate is increased. This is because there is a case where the decrease occurs. Accordingly, since the balance between the heat resistance and adhesion of the cured film is better, the glass transition point of the cured film is more preferably set to a value within the range of 50 to 85 ° C, and within the range of 60 to 80 ° C. More preferably, the value of
The glass transition point of the cured film can be calculated from the change point of the specific heat obtained by performing differential scanning thermal analysis (DSC) and heating at a rate of temperature increase of 10 ° C./min in nitrogen as an example. it can.
[0059]
Moreover, normally, in the cured film obtained from the curable resin composition, one glass transition point is obtained (see FIG. 4). This is because the curable resin composition of the present invention is a hexafluoropropylene copolymer. This is probably because the compatibility between the coalescence and the α-fluoroacrylate monomer is good. That is, normally, the glass transition point of the hexafluoropropylene copolymer, for example, the polymer A1 used in Example 1 described later, is in the range of 0 to 40 ° C. (see FIG. 5). On the other hand, the glass transition point of a polymer of α-fluoroacrylate monomer, for example, trifluoroethyl α-fluoroacrylate monomer alone is in the range of 100 to 120 ° C. Therefore, the single glass transition point of the cured film means that the hexafluoropropylene copolymer and the α-fluoroacrylate polymer are uniformly compatible and not chemically bonded, but the glass transition point. One point appears to appear.
[0060]
Therefore, such a glass transition point can be easily adjusted according to the following formula.
1 / T_p= W_H/ T_H+ W_F/ T_F
T_p: Glass transition point of cured film (absolute temperature)
T_H: Hexafluoropropylene copolymer glass transition point (absolute temperature)
T_F: Glass transition point of α-fluoroacrylate polymer (absolute temperature)
w_H: Weight fraction of hexafluoropropylene copolymer (%)
w_F: Α-fluoroacrylate polymer weight fraction (%)
[0061]
However, depending on the type of additive component of the curable resin composition, two or more glass transition points may be obtained in the cured film. In that case, what is necessary is just to adjust the kind of a mixing ratio, a hexafluoropropylene copolymer, and (alpha) -fluoro acrylate monomer so that the value of a high glass transition point may become a value within the range of 40-90 degreeC.
[0062]
[Second Embodiment]
In the second embodiment, a hexafluoropropylene copolymer containing a siloxane bond, an α-fluoroacrylate monomer, and an ethylenically unsaturated compound copolymerizable with the α-fluoroacrylate monomer (hereinafter simply referred to as ethylenically unsaturated). A curable resin composition containing a radiation polymerization initiator.
By including an ethylenically unsaturated compound other than the α-fluoroacrylate monomer in this way, the viscosity of the curable resin composition, the refractive index of the resulting cured film, adhesion, mechanical strength, etc. can be easily adjusted. can do.
In the following description, the ethylenically unsaturated compound that is the feature of the second embodiment will be mainly described, and the other components and the like may be the same as those of the first embodiment.
[0063]
(1) Kind
The ethylenically unsaturated compound copolymerizable with the α-fluoroacrylate monomer is heated by irradiation with active energy rays in the presence or absence of a photopolymerization initiator or in the presence of a thermal polymerization initiator. Is a compound that undergoes addition polymerization.
Specific examples of such ethylenically unsaturated polymerizable compounds include α-olefins such as ethylene, propylene, and isobutene; styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, diisopropenylbenzene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 1,1-diphenylethylene, p-methoxystyrene, N, N-dimethyl-p-aminostyrene, Vinyl aromatic compounds such as N, N-diethyl-p-aminostyrene, vinyl pyridine and vinyl imidazole; carboxyl group-containing compounds such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid; methyl (meta ) Acrylate, ethyl (meth) acrylate, propyl (meth) Acrylate), isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, hexyl ( (Meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl ( Alkyls such as (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate ( ) Acrylates; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate; phenoxyethyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl Phenoxyalkyl (meth) acrylates such as (meth) acrylate; methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxybutyl (meth) acrylate, etc. Alkoxyalkyl (meth) acrylates; polyethylene glycol mono (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxypoly Polyethylene glycol (meth) acrylates such as tylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate; polypropylene glycol mono (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, ethoxy Polypropylene glycol (meth) acrylates such as polypropylene glycol (meth) acrylate and nonylphenoxy polypropylene glycol (meth) acrylate; cyclohexyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, di Cyclopentenyl (meth) acrylate, dicyclopentadienyl (meth) Cycloalkyl (meth) acrylates such as acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate; one kind alone such as benzyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate or A combination of two or more types can be mentioned.
[0064]
(2) Addition amount
The addition amount of the ethylenically unsaturated compound is not particularly limited. Specifically, the addition amount is a value within the range of 1 to 1,000 parts by weight with respect to 100 parts by weight of the α-fluoroacrylate monomer. Is preferable. The reason for this is that when the addition amount of the ethylenically unsaturated compound is less than 1 part by weight, the effect of addition may not be obtained, while the addition amount of the ethylenically unsaturated compound is 1,000 parts by weight. This is because if it exceeds, the compatibility of the curable resin composition is lowered, and a precipitate may be formed or the curing reaction may be uneven.
Therefore, it is more preferable to set the addition amount of the ethylenically unsaturated compound to a value within the range of 2 to 100 parts by weight with respect to 100 parts by weight of the α-fluoroacrylate monomer, and a value within the range of 5 to 50 parts by weight. More preferably.
[0065]
[Third Embodiment]
The third embodiment of the present invention is an antireflection film made of the curable resin composition described in the first and second embodiments. In addition, this antireflection film should just be provided on the base material, and can take various modifications as a laminated body. Hereinafter, the antireflection film (laminated body) of the third embodiment will be specifically described with reference to FIGS. FIG. 1 is a cross-sectional view of a laminate 14 including an antireflection film 10 formed directly on a substrate 12, and FIG. 2 shows a hard coat layer 16 interposed between the substrate 12 and the antireflection film 10. It is sectional drawing of the made laminated body 18. FIG. Also, FIG. 3 shows, from the bottom, the base material 12, the hard coat layer 16, the first high refractive index layer 20, the first antireflection film 22, the second high refractive index layer 24, It is sectional drawing of the laminated body 28 of the multilayer structure comprised by forming the 2nd antireflection film 26 in order.
[0066]
In the case of the laminate 14 shown in FIG. 1, the antireflection film 10 made of the curable resin composition described in the first and second embodiments can be directly formed on the base material 12, so that the configuration is a single layer. However, it is simple and can be formed with high accuracy.
Moreover, when the hard coat layer 16 is interposed between the antireflection film 10 and the base material 12 as in the laminate 18 shown in FIG. 2, the adhesion of the antireflection film 10 to the base material 12 is further improved. In addition, the durability of the laminate 18 is further improved due to the mechanical properties of the hard coat layer 16. The hard coat layer 16 is made of, for example, SiO.₂, Epoxy resin, acrylic resin, melamine resin, and the like are preferable. Further, the thickness is preferably set to a value in the range of 1 to 50 μm, more preferably 5 to 10 μm. The value is within the range.
[0067]
In addition to the first and second antireflection layers 22 and 26 as in the laminated body 28 shown in FIG. 3, a relatively high refractive index value, for example, 1.5 to 2.0 (−). It is also preferable to provide the first and second high refractive index layers 20 and 24 having a thickness within the range and having a thickness of 50 to 200 nm in contact with the first and second antireflection layers 22 and 26, respectively. In this way, by providing the high refractive index layers 20 and 24 in contact with the antireflection layer of the present invention and providing a plurality of layers, a more excellent antireflection effect can be obtained.
Further, when the high refractive index layers 20 and 24 are provided, a better antireflection effect can be obtained. Therefore, the refractive index difference between the antireflective layers 22 and 26 and the high refractive index layers 20 and 24 is set to 0. It is preferable to set it as the value of 05 (-) or more, It is more preferable to set it as the value within the range of 0.1-0.5 (-), The value within the range of 0.15-0.5 (-) More preferably.
[0068]
Further, when the hard coat layer 16, the high refractive index layers 20, 24, or the primer layer (not shown) is provided as shown in the laminates 18 and 28 in FIGS. By coating the photocurable composition and then irradiating ultraviolet rays or the like, the antireflection films 10, 22, and 26 made of the curable resin composition of the first and second embodiments can be easily formed. In that case, the high refractive index layers 20 and 24 that bear one end of the antireflection effect may be referred to as the antireflection film (antireflection layer) of the present invention.
[0069]
Moreover, the kind of the base material 12 in the laminates 14, 18, and 28 shown in FIGS. 1 to 3 is not particularly limited as long as an antireflection effect is desired when light is transmitted. For example, glass, polycarbonate resin, polyester resin or acrylic resin can be used. In the case where the substrate 12 is made of glass, examples of a specific laminate include a camera lens unit, a television (CRT, LCD) screen display unit, and a window glass. Moreover, in the case of the base material 12 which consists of a polycarbonate-type resin, a polyester-type resin, or an acrylic resin, the color filter etc. in a liquid crystal display device are mentioned.
[0070]
【Example】
Hereinafter, embodiments of the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples without departing from the gist thereof. Unless otherwise indicated, parts and% in the examples represent parts by weight and% by weight, respectively.
[0071]
[Synthesis of hexafluoropropylene copolymer]
(1) Polymer A1
In carrying out Examples 1 to 5 and Comparative Examples 1 to 4, a hexafluoropropylene copolymer as a polymer A1 was synthesized. That is, after a stainless steel autoclave with an electromagnetic stirrer with an internal volume of 1.5 liters was sufficiently replaced with nitrogen gas, as shown in Table 1, 600 g of ethyl acetate as a solvent and a single amount copolymerizable with hexafluoropropylene (HFP) As a body, 31.9 g of perfluoro (propyl vinyl ether) (FPVE), 30.2 g of ethyl vinyl ether (EVE), and 15.8 g of hydroxyethyl vinyl ether (HEVE), Adekaria soap NE-30 (Asahi) as a nonionic reactive emulsifier VPS-1001 (Wako Pure Chemical Industries, Ltd.) as an azo group-containing polydimethylsiloxane manufactured by Denka Kogyo Co., Ltd., 30.0 g of an emulsifier in which n in the general formula (3) is 9, m is 1, and s is 30 Manufactured) 1.28 g and dilauroyl peroxide (LPO) 0.75 g Were charged, dry ice - After cooling to -50 ° C. in methanol, it was sufficiently replaced with nitrogen gas again.
[0072]
Subsequently, 86.4 g of hexafluoropropylene was introduced into the autoclave, and then the temperature was raised. The pressure when the temperature in the autoclave reaches 60 ° C. is 4.7 kgf / cm.²showed that. Thereafter, the reaction was continued with stirring at 60 ° C. for 25 hours, and the pressure was 2.5 kgf / cm.²The autoclave was cooled with water at the time when the temperature decreased to stop the reaction. After reaching room temperature, the unreacted monomer was released and the autoclave was opened to obtain a polymer solution. The obtained polymer solution was put into methanol to precipitate a polymer, washed with methanol, and further vacuum dried at 50 ° C. to obtain 129 g of a hexafluoropropylene copolymer (polymer A1) containing a siloxane bond. .
[0073]
The obtained polymer A1 was adjusted with THF so that the concentration became a 0.5 wt% solution, and the molecular weight was measured by gel permeation chromatography. As a result, the number average molecular weight in terms of polystyrene was 76,800. Furthermore, the glass transition temperature (Tg) by DSC analysis and the fluorine content by the alizarin complexone method were measured, respectively. The obtained results are shown in Table 1.
In addition,¹H-NMR,¹³C-NMR analysis results, elemental analysis results, fluorine content, hydroxyl value, and further, the residual silica after calcination at 600 ° C. are used to measure the inorganic silica content. From these measurements, the proportion of each monomer component constituting the polymer A1 is determined. Were determined. As a result, the molar ratio of HFP / FPVE / EVE / HEVE / NE-30 / (constituent component according to VPS-1001) = 39.7 / 9.7 / 33.8 / 13.6 / 1.1 / 2.1 It was confirmed that.
Therefore, the obtained polymer A1 surely contains a polysiloxane bond derived from VPS-1001, and, among the constituent components in the copolymer, only the charge ratio and the constituent component ratio of NE-30. It was found that there was a difference.
[0074]
(2) Polymer A2
In carrying out Comparative Example 5, a hexafluoropropylene copolymer containing no siloxane bond as the polymer A2 was synthesized. That is, in the composition shown in Table 1, the polymer A2 was synthesized in the same manner as the polymer A1. With respect to the obtained polymer A2, the number average molecular weight, the fluorine content, and the glass transition temperature were measured in the same manner as in the polymer A1. The obtained results are shown in Table 1.
Moreover, the ratio of each monomer component which comprises polymer A2 was determined similarly to polymer A1. As a result, it was confirmed that the molar ratio was HFP // EVE = 49.8 / 50.2.
[0075]
[Table 1]

[0076]
In addition, the symbol in Table 1 has shown the following content.
HFP: Hexafluoropropylene
FPVE: Perfluoro (propyl vinyl ether)
EVE: Ethyl vinyl ether
HEVE: hydroxyethyl vinyl ether
VPS-1001: azo group-containing polydimethylsiloxane (manufactured by Wako Pure Chemical Industries, Ltd., number average molecular weight is 80,000, polysiloxane portion has a molecular weight of about 10,000)
NE-30: Nonionic reactive emulsifier NE-30 (Asahi Denka Kogyo Co., Ltd.)
LPO: Dilauroyl peroxide
[0077]
[Synthesis of α-Fluoroacrylate Monomer]
After dropping 42 g of methyl-α-fluoroacrylate into a mixed solution consisting of 600 mL of 1N aqueous sodium hydroxide solution contained in a 2 L container, 600 mL of tetrahydrofuran, and 0.08 g of p-methoxyphenol under ice cooling, 4 Stir for hours to react. The obtained reaction solution was concentrated under the conditions of an oil bath temperature of 30 ° C. and a degree of vacuum of 150 mmHg. Thereafter, 700 mL of 1N hydrochloric acid was slowly added to make the aqueous layer acidic, and extracted with 400 mL of methylene chloride to obtain an organic layer. The organic layer was then dried over anhydrous magnesium sulfate and filtered. The obtained filtrate was concentrated to obtain 28.8 g of α-fluoroacrylic acid as a white solid.
In a mixed solution consisting of 24 g of the obtained α-fluoroacrylic acid, 26.5 g of trifluoroethanol, 0.01 g of p-methoxyphenol, and 84.0 g of methylene chloride, 52.1 g of concentrated sulfuric acid was cooled with ice. Slowly dripped. After completion of dropping, the mixture was stirred while being heated in a 40 ° C. oil bath. After 20 hours, the reactor was removed from the oil bath, and 500 mL of ice water was slowly added with ice water. This was extracted three times with 300 mL of methylene chloride to obtain an organic layer. The organic layer was washed with a saturated aqueous sodium hydrogen carbonate solution and brine, further dried over magnesium sulfate, and then filtered. The obtained filtrate was concentrated and purified by distillation under reduced pressure to obtain 23 g of trifluoroethyl α-fluoroacrylate. The yield was 86%.
[0078]
[Example 1]
As shown in Table 2, 10.0 g of the obtained hexafluoropropylene copolymer (A1) containing a siloxane bond and 3.0 g of Irgacure 184 which is a radiation polymerization initiator were mixed with 90 g of trifluoroethyl α-fluoroacrylate. After being dissolved therein, a curable resin composition was obtained by stirring at room temperature for 2 hours using a mixer without solvent.
The obtained curable resin composition (no solvent) was evaluated for (1) radiation curability and (2) coatability. Moreover, (3) transparency and (4) refractive index were measured about the cured film formed from the curable resin composition. The obtained results are shown in Table 2.
[0079]
(1) Radiation curable
A curable resin composition was coated on a glass plate cut into 20 × 30 cm square with a bar coater to form a coating film having a thickness of 200 μm. Next, the exposure amount is 300 mJ / cm in nitrogen at 25 ° C.²(Irradiation time 3 seconds), 600 mJ / cm²(Irradiation time 6 seconds), and 900 mJ / cm²A cured film was formed by irradiating with ultraviolet rays using a conveyor type high pressure mercury lamp (2 kW) manufactured by Oak Manufacturing Co., Ltd. so that the irradiation time was 9 seconds. About the obtained cured film, surface tack was measured by finger touch and the radiation curability (photocurability) of the curable resin composition was evaluated according to the following criteria.
A: 300 mJ / cm²There is no surface tack of the cured film after exposure.
○: 600 mJ / cm²There is no surface tack of the cured film after exposure.
Δ: 900 mJ / cm²There is no surface tack of the cured film after exposure.
×: 900 mJ / cm²After exposure, there is a surface tack of the cured film.
[0080]
(2) Applicability
A curable resin composition is applied to a polycarbonate plate having a thickness of 2 mm and a size of 10 cm square with a dip coater to a thickness of 1 μm, and is exposed in nitrogen using a high-pressure mercury lamp so that an exposure amount is 900 mJ. A cured film was obtained. About the obtained cured film, the presence or absence of the coating unevenness was judged visually by the following reference | standard, and coating property was evaluated.
○: No coating unevenness.
Δ: Slightly uneven coating.
X: There is uneven coating.
[0081]
(3) Transparency
A curable resin composition was coated on a glass plate cut into 20 × 30 cm square with a bar coater to form a coating film having a thickness of 200 μm. Next, under nitrogen at 25 ° C., 900 mJ / cm²The cured film was formed by irradiating with ultraviolet rays using the above-described conveyor type high-pressure mercury lamp so that the irradiation time was 9 seconds. With respect to the obtained cured film, the transparency was evaluated visually according to the following criteria.
○: Transparent
Δ: Slightly cloudy
X: cloudiness
[0082]
(4) Refractive index
A curable resin composition was applied to a glass plate cut into 20 × 30 cm square with a bar coater to form a coating film having a thickness of 200 μm. Next, under nitrogen at 25 ° C., 900 mJ / cm²The cured film was formed by irradiating with ultraviolet rays using the above-described conveyor type high-pressure mercury lamp so that the irradiation time was 9 seconds. About the obtained cured film, the refractive index was measured on the conditions of measurement temperature 25 degreeC using the Abbe refractometer.
[0083]
[Examples 2-3]
As shown in Table 2, a curable resin composition (solvent-free) was produced in the same manner as in Example 1 except that the composition was changed by changing the type and addition amount of α-fluoroacrylate. The obtained curable resin composition was evaluated for radiation curability and coatability, and the transparency of the obtained cured film was evaluated in the same manner as in Example 1. The obtained results are shown in Table 2.
[0084]
[Examples 4 to 5]
As shown in Table 2, a curable resin composition (using a solvent) was produced in the same manner as in Example 1 except that the type and amount of α-fluoroacrylate were changed and a solvent was added. And radiation sclerosis | hardenability and applicability | paintability were evaluated about the obtained curable resin composition, and transparency and refractive index were evaluated similarly to Example 1 about the obtained cured film. Further, the obtained cured film was further evaluated for reflectivity and adhesion as follows. The obtained results are shown in Table 2.
[0085]
(5) Reflectance
A curable resin composition was applied on a polycarbonate plate having a thickness of 2 mm and a size of 10 cm square by a dip coater to a thickness of 1 μm, and then 900 mJ / cm in a nitrogen atmosphere using a high-pressure mercury lamp.²Then, an antireflection film was formed. A matte black spray (trade name: Quick-dry acrylic lacquer spray matte black, manufactured by Campe Pio Co., Ltd.) was applied to the back surface of the polycarbonate plate and dried. Using this as a measurement sample, the reflectance at a wavelength of 550 nm was measured using a spectrophotometer with a 60 mmφ integrating sphere (U-3410, manufactured by Hitachi, Ltd.).
[0086]
(6) Measurement of adhesion
A curable resin composition was applied on a polycarbonate plate having a thickness of 2 mm and a size of 10 cm square with a dip coater to a thickness of 1 μm, and then 900 mJ / cm in a nitrogen atmosphere with a high-pressure mercury lamp.²Then, an antireflection film was formed. Using this as a measurement sample, the surface of the cured film was rubbed using Kimwipe (manufactured by Jujo Kimberley Co., Ltd.), and the adhesion (abrasion resistance) of the antireflection film to the polycarbonate plate was evaluated according to the following criteria.
○: There is no peeling or scratching of the coating film.
X: Peeling occurs in a part of the coating film, or streak damage occurs on the coating film surface.
[0087]
[Comparative Examples 1-3]
As shown in Table 2, a curable resin composition (solvent-free) was produced in the same manner as in Example 1 except that the composition was formed using a fluoroacrylate other than α-fluoroacrylate. The obtained curable resin composition was evaluated for radiation curability and applicability, and the cured film obtained was evaluated for transparency, refractive index, and reflectance in the same manner as in Example 1. The obtained results are shown in Table 2.
[0088]
[Comparative Example 4]
As shown in Table 2, a curable resin composition (using a solvent) was produced in the same manner as in Example 4 except that the composition was prepared using a fluoroacrylate other than α-fluoroacrylate. The obtained curable resin composition was evaluated for radiation curability and applicability, and the cured film obtained was evaluated for transparency, refractive index, and reflectance in the same manner as in Example 1. The obtained results are shown in Table 2.
[0089]
[Table 2]

[0090]
In addition, the symbol in Table 2 has shown the following content. In Table 2, component (A) represents a hexafluoropropylene copolymer containing a siloxane bond, component (B) represents α-fluoroacrylate, and component (C) represents a fluoroacrylate other than α-fluoroacrylate. The component (D) represents a polymerization initiator, and the component (E) represents a solvent.
ARF3F: trifluoroethyl α-fluoroacrylate
ARF4F: 2,2,3,3-tetrafluoropropyl α-fluoroacrylate
Irg. 184: 1-hydroxy-cyclohexyl-phenyl-ketone
(Ciba Specialty Chemicals Co., Ltd.)
3F: trifluoroethyl acrylate
8F: Octafluoropentyl acrylate
NP-A: Neopentyl glycol diacrylate (manufactured by Kyoeisha Yushi Chemical Co., Ltd.)
MIBK: Methyl isobutyl ketone
[0091]
【The invention's effect】
According to the curable resin composition of the present invention, the combination of a hexafluoropropylene copolymer having a siloxane bond and an α-fluoroacrylate monomer provides a particularly good compatibility without using a solvent. In addition, excellent radiation curability and coating properties can be obtained.
Therefore, the curable resin composition of the present invention can be used as an antireflection film or an antifouling film on the substrate surface, and is also suitably used as an adhesive, a sealant, or an optical fiber clad material. be able to.
[0092]
Moreover, according to the cured film of this invention, while having the outstanding adhesiveness with respect to a base material, it came to be able to obtain the low transparency and the outstanding transparency with respect to visible light. Therefore, the cured film of the present invention can exhibit excellent durability and optical characteristics when used as an antireflection film or an antifouling film.
[0093]
Moreover, according to the antireflection film of the present invention, not only the characteristics as the cured film described above can be obtained, but also a low reflectance, for example, a value of 2% or less can be obtained.
Furthermore, since the antireflection film of the present invention is cross-linked, it has high mechanical strength and has a hardness suitable for exhibiting scratch resistance and surface slidability (abrasion resistance). Since it has a siloxane bond and a fluorine group, it is expected to have excellent weather resistance.
[Brief description of the drawings]
FIG. 1 is a view showing a cross section of a laminate including an antireflection film of the present invention (No. 1).
FIG. 2 is a view showing a cross section of a laminate including the antireflection film of the present invention (part 2).
FIG. 3 is a view showing a cross section of a laminate including the antireflection film of the present invention (No. 3).
FIG. 4 is a DSC measurement chart of a hexafluoropropylene copolymer containing a siloxane bond.
FIG. 5 is a DSC measurement chart of a cured film obtained from the curable resin composition of the present invention.
[Explanation of symbols]
10, 22, 26 Antireflection film
12 Base material
14, 18, 28 Laminate
16 Hard coat layer
20, 22 High refractive index layer

Claims (8)

An active energy ray-curable resin composition comprising a hexafluoropropylene copolymer containing a siloxane bond and an α-fluoroacrylate monomer. The active energy ray-curable resin composition according to claim 1, wherein the α-fluoroacrylate monomer is a compound represented by the following general formula (1).
CH ₂ = CF-COOR _f (1)
[In General Formula (1), R _f is a hydrocarbon group having at least one fluorine atom which may contain an oxygen atom. ] The active energy ray-curable resin composition according to claim 1 or 2, wherein the hexafluoropropylene copolymer containing a siloxane bond is a copolymer obtained by using an azo group-containing polysiloxane compound. object. The active energy ray according to any one of claims 1 to 3, wherein the hexafluoropropylene copolymer containing a siloxane bond is a copolymer obtained using a nonionic reactive emulsifier. Curable resin composition. The amount of hexafluoropropylene units in 100 mol% of the hexafluoropropylene copolymer containing a siloxane bond is set to a value within the range of 20 to 70 mol%. The active energy ray-curable resin composition described. The amount of the α-fluoroacrylate monomer added to a value within the range of 1 to 10,000 parts by weight with respect to 100 parts by weight of the hexafluoropropylene copolymer containing the siloxane bond. The active energy ray-curable resin composition according to any one of -5. The cured film formed by hardening | curing the active energy ray-curable resin composition as described in any one of Claims 1-6 with an active energy ray. The antireflection film formed by hardening | curing the curable resin composition as described in any one of Claims 1-6 with an active energy ray on a base material.

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