JP4138200B2 - Photocatalyst-containing composition, wettability changing film, and method for producing wettability changing resin composition - Google Patents

Description

【００６４】
ただし、ｍは２以上の整数であり、Ｒ¹，Ｒ²はそれぞれ炭素数１〜１０の置換もしくは非置換のアルキル、アルケニル、アリールあるいはシアノアルキル基であり、モル比で全体の４０％以下がビニル、フェニル、ハロゲン化フェニルである。また、Ｒ¹、Ｒ²がメチル基のものが表面エネルギーが最も小さくなるので好ましく、モル比でメチル基が６０％以上であることが好ましい。また、鎖末端もしくは側鎖には、分子鎖中に少なくとも１個以上の水酸基等の反応性基を有する。
【００６５】
また、上記のオルガノポリシロキサンとともに、ジメチルポリシロキサンのような架橋反応をしない安定なオルガノシリコン化合物をバインダに混合してもよい。
【００６６】
本発明において光触媒含有層には上記の光触媒、バインダの他に、界面活性剤を含有させることができる。具体的には、日光ケミカルズ（株）製ＮＩＫＫＯＬＢＬ、ＢＣ、ＢＯ、ＢＢの各シリーズ等の炭化水素系、デュポン社製ＺＯＮＹＬ ＦＳＮ、ＦＳＯ、旭硝子（株）製サーフロンＳ−１４１、１４５、大日本インキ化学工業（株）製メガファックＦ−１４１、１４４、ネオス（株）製フタージェントＦ−２００、Ｆ２５１、ダイキン工業（株）製ユニダインＤＳ−４０１、４０２、スリーエム（株）製フロラードＦＣ−１７０、１７６等のフッ素系あるいはシリコーン系の非イオン界面活性剤を挙げることかでき、また、カチオン系界面活性剤、アニオン系界面活性剤、両性界面活性剤を用いることもできる。
【００６７】
また、光触媒含有層には上記の界面活性剤の他にも、ポリビニルアルコール、不飽和ポリエステル、アクリル樹脂、ポリエチレン、ジアリルフタレート、エチレンプロピレンジエンモノマー、エポキシ樹脂、フェノール樹脂、ポリウレタン、メラミン樹脂、ポリカーボネート、ポリ塩化ビニル、ポリアミド、ポリイミド、スチレンブタジエンゴム、クロロプレンゴム、ポリプロピレン、ポリブチレン、ポリスチレン、ポリ酢酸ビニル、ポリエステル、ポリブタジエン、ポリベンズイミダゾール、ポリアクリルニトリル、エピクロルヒドリン、ポリサルファイド、ポリイソプレン等のオリゴマー、ポリマー等を含有させることができる。
【００６８】
本発明においては、濡れ性変化層に光触媒を含有させてもよい。濡れ性変化層に光触媒を含有させる場合には、上記したオルガノポリシロキサン化合物のような適切なバインダーに光触媒を混合して光触媒含有組成物を調製し、これを基板上に塗布し、乾燥又は硬化させるのが好ましい。
【００６９】
後述するような酸化チタンに代表される光触媒の作用機構は、必ずしも明確なものではないが、光の照射によって生成したキャリアが、近傍の化合物との直接反応、あるいは、酸素、水の存在下で生じた活性酸素種によって、有機物の化学構造に変化を及ぼすものと考えられている。そして、本発明においては、このキャリアが濡れ性変化層中のバインダーやその他の化合物に作用を及ぼして、高親水化させるものと思われる。
【００７０】
本発明で使用する光触媒としては、光半導体として知られる例えば酸化チタン（ＴｉＯ₂）、酸化亜鉛（ＺｎＯ）、酸化スズ（ＳｎＯ₂）、チタン酸ストロンチウム（ＳｒＴｉＯ₃）、酸化タングステン（ＷＯ₃）、酸化ビスマス（Ｂｉ₂Ｏ₃）、および酸化鉄（Ｆｅ₂Ｏ₃）を挙げることができ、これらから選択して１種または２種以上を混合して用いることができる。
【００７１】
本発明においては、特に酸化チタンが、バンドギャップエネルギーが高く、化学的に安定で毒性もなく、入手も容易であることから好適に使用される。酸化チタンには、アナターゼ型とルチル型があり本発明ではいずれも使用することができるが、アナターゼ型の酸化チタンが好ましい。アナターゼ型酸化チタンは励起波長が３８０ｎｍ以下にある。
【００７２】
このようなアナターゼ型酸化チタンとしては、例えば、塩酸解膠型のアナターゼ型チタニアゾル（石原産業（株）製ＳＴＳ−０２（平均粒径７ｎｍ）、石原産業（株）製ＳＴ−Ｋ０１）、硝酸解膠型のアナターゼ型チタニアゾル（日産化学（株）製ＴＡ−１５（平均粒径１２ｎｍ））等を挙げることができる。
【００７３】
光触媒の粒径は小さいほど光触媒反応が効果的に起こるので好ましく、平均粒径が５０ｎｍ以下のものが好ましく、２０ｎｍ以下の光触媒を使用するのが特に好ましい。また、光触媒の粒径が小さいほど、形成された光触媒含有層の表面粗さが小さくなるので好ましく、光触媒の粒径が１００ｎｍを越えると光触媒含有層の中心線平均表面粗さが粗くなり、光触媒含有層の非露光部の撥インキ性が低下し、また露光部の親インキ性の発現が不十分となるため好ましくない。
【００７４】
濡れ性変化層に光触媒を添加する場合の含有量は、５〜６０重量％、好ましくは２０〜４０重量％の範囲で設定することができる。
【００７５】
このような濡れ性変化層は、上述した成分を、必要に応じて他の添加剤とともに溶剤中に分散して塗布液を調製し、この塗布液を基板又は光触媒含有層の上に塗布することにより形成できる。使用する溶剤としては、エタノール、イソプロパノール等のアルコール系の有機溶剤が好ましい。塗布はスピンコート、スプレーコート、ディップコート、ロールコート、ビードコート等の公知の塗布方法により行うことができる。バインダとして紫外線硬化型の成分を含有している場合、紫外線を照射して硬化処理を行うことにより濡れ性変化層を形成することかできる。
【００７６】
本発明においては、濡れ性変化層の厚みは、濡れ性変化層に光触媒を含有させるのか、或いは、独立して設けた光触媒含有層の上に濡れ性変化層を形成するのかによって、適宜調節されるが、一般的には、０．００１μｍ〜１μｍであることが好ましく、特に好ましくは０．００１μｍ〜０．２μｍの範囲内である。
【００７７】
本発明においては、露光前の濡れ性変化層が、ホルムアミドとエチレングリコールモノエチルエーテルを混合してなる濡れ標準試薬の接触角（θ）、及び、当該接触角から導かれるコサイン値（ｃｏｓθ）の平均減少率の絶対値（｜Ｘ｜）が、上記所定の範囲内に入るように、材料を選んで濡れ性変化層を形成する必要がある。
【００７８】
このような特性を有する濡れ性変化層を作成する好適な方法としては、次のような方法がある。すなわち、フルオロアルキル基を含有する珪素化合物の１種又は２種以上を、酸と水の存在下で加水分解縮合又は共加水分解縮合させることによって濡れ性変化層用組成物を調製する。加水分解縮合可能なフルオロアルキル基含有珪素化合物としては、上記一般式Ｙ_nＳｉＸ_(4-n)で表される珪素化合物の中からフルオロアルキル基を含有するもの、すなわち下記一般式
Ｙ_pＳｉＸ_(4-p)
（Ｙは水素、又は、置換基を有していてもよい炭化水素基を示す。一分子中の複数のＹは互いに同じであっても異なってもよい。ただし、少なくとも一のＹはフルオロアルキル基又はフルオロアルキル基を有する炭化水素基である。Ｘはアルコキシル基、アセチル基又はハロゲンを示す。一分子中の複数のＸは互いに同じであっても異なってもよい。ｐは１〜３までの整数である。）
で表される珪素化合物を選んで用いることができる。
【００７９】
また、フルオロアルキル基含有珪素化合物は、必要に応じて、加水分解縮合可能な珪素化合物、好ましくは上記一般式Ｙ_nＳｉＸ_(4-n)で表される珪素化合物であってフルオロアルキル基を含有しないもの、と混合して共加水分解縮合させてもよい。
【００８０】
上記したようなフルオロアルキル基含有珪素化合物、好ましくは上記一般式Ｙ_pＳｉＸ_(4-p)で表される珪素化合物、及び、必要に応じてその他の珪素化合物を、イソプロピルアルコールのような水溶性溶剤に投入し、２規定程度の塩酸などの適当な酸を用いて必要量の水と酸を加えると、酸性ｐＨの水性反応系が得られる。この水性反応系の調製液を、適当な温度で適当な時間、攪拌することによりゾルゲル反応させると、フルオロアルキル基含有珪素化合物が加水分解縮合し、濡れ性変化層用組成物が得られる。フルオロアルキル基含有珪素化合物、その他の珪素化合物、溶剤、水、酸などの各材料の混合順序は特に制限されない。
【００８１】
フルオロアルキル基含有珪素化合物は、過剰の水と酸の存在下でゾルゲル反応させることによって加水分解縮合させるのが好ましい。具体的には、反応系において、フルオロアルキル基含有珪素化合物及び必要に応じて混合されるフルオロアルキル基を含有しない珪素化合物を含む、加水分解縮合可能な珪素化合物の合計量に対して、水の割合がモル比で通常は２００倍以上、好ましくは３００倍以上、さらに好ましくは４００倍以上となり、且つ、反応系のｐＨが２以下となるように調節する。
【００８２】
フルオロアルキル基含有珪素化合物を含有し且つ水と酸を添加された水性反応系の調製液は、通常２５〜１００℃、好ましくは５０〜１００℃に加熱しながら、１０分〜２４時間、好ましくは１時間〜８時間、攪拌しながらゾルゲル反応を進行させる。
【００８３】
ゾルゲル反応させて得られた反応液は、フルオロアルキル基含有珪素化合物、その他の珪素化合物、それらの加水分解物、及び、それらの脱水縮合物の混合物である。このようにして得られた反応液は、そのまま濡れ性変化層用組成物として使用することができる。或いは、ゾルゲル反応によって得られた反応液から、必要に応じて水を除去し、塗工用溶剤に溶解・分散させ、その他の添加剤を加えて、濡れ性変化層用組成物を調製してもよい。このようにして得られた濡れ性変化層用組成物を基板又は光触媒含有層の上に塗布し、乾燥させることによって、フルオロアルキル基含有珪素化合物を縮合単位とする加水分解縮合物又は共加水分解縮合物からなる濡れ性変化層が形成される。濡れ性変化層用組成物を基板又は光触媒含有層の上に塗布した後で加熱することにより、塗膜の乾燥中に加水分解縮合反応がさらに進行するので、珪素化合物を十分に縮合させることができる。このようにして形成された濡れ性変化層は、上記特定の接触角（θ）及びｃｏｓθの平均減少率の絶対値（｜Ｘ｜）を示す。
【００８４】
また、上記調製法によって、光触媒を含有する濡れ性変化層用組成物（光触媒含有組成物）を形成したい場合には、上記反応系に光触媒を混合して加水分解縮合を行ってもよいし、加水分解縮合によって得られた濡れ性変化層用組成物に光触媒を混合してもよい。例えば、上記したようなフルオロアルキル基含有珪素化合物に光触媒の微粉末を投入し、この混合物を水と酸の存在下でゾルゲル反応させて加水分解縮合させることにより、光触媒含有組成物が得られる。或いは、フルオロアルキル基含有珪素化合物を水と酸の存在下でゾルゲル反応させて加水分解縮合させた後、得られた反応液、又は、反応液から水を除去して得られた加水分解縮合物、又は、当該縮合物を再び溶剤に溶解又は分散した液体に、光触媒を混合してもよい。このようにして得られた光触媒含有組成物を基板の上に塗布し、乾燥又は硬化させることによって、光触媒を含有し、且つ、上記特定の接触角（θ）及びｃｏｓθの平均減少率の絶対値（｜Ｘ｜）を示す濡れ性変化層を形成することができる。
【００８５】
（光触媒含有層）
本発明においては、上記したような光触媒を含有する光触媒含有層を、濡れ性変化層とは独立して設けてもよい。この光触媒含有層は、光触媒含有層中の光触媒がその上に形成された濡れ性変化層の濡れ性を変化させるような構成であれば、特に限定されるものではなく、光触媒とバインダーとから構成されているものであってもよいし、光触媒単体で成膜されたものであってもよい。また、その表面の濡れ性は特に親インキ性であっても撥インキ性であってもよいが、この光触媒含有層上に、濡れ性変化層等を形成する都合上、親インキ性であることが好ましい。
【００８６】
光触媒含有層を光触媒単独で形成する場合、例えば二酸化チタンの場合は、基板上に無定形チタニアを形成し、次いで焼成により結晶性チタニアに相変化させる方法等が挙げられる。ここで用いられる無定形チタニアとしては、例えば四塩化チタン、硫酸チタン等のチタンの無機塩の加水分解、脱水縮合、テトラエトキシチタン、テトライソプロポキシチタン、テトラ−ｎ−プロポキシチタン、テトラブトキシチタン、テトラメトキシチタン等の有機チタン化合物を酸存在下において加水分解、脱水縮合によって得ることができる。次いで、４００℃〜５００℃における焼成によってアナターゼ型チタニアに変性し、６００℃〜７００℃の焼成によってルチル型チタニアに変性することができる。
【００８７】
また、光触媒含有層にバインダを用いる場合は、バインダの主骨格が上記の光触媒の光励起により分解されないような高い結合エネルギーを有するものが好ましく、例えばこのようなバインダとしては、前述したようなオルガノポリシロキサン化合物等を挙げることができる。
【００８８】
このようにオルガノポリシロキサン化合物をバインダとして用いた場合は、光触媒とオルガノポリシロキサン化合物を必要に応じて他の添加剤とともに溶剤中に溶解、分散して塗布液を調製し、この塗布液を基板上に塗布することにより、光触媒含有層を形成することができる。使用する溶剤としては、エタノール、イソプロパノール等のアルコール系の有機溶剤が好ましい。塗布はスピンコート、スプレーコート、ディップコート、ロールコート、ビードコート等の公知の塗布方法により行うことができる。バインダとして紫外線硬化型の成分を含有している場合、紫外線を照射して硬化処理を行うことにより光触媒含有層を形成することかできる。
【００８９】
また、バインダとして無定形シリカ前駆体を用いることができる。この無定形シリカ前駆体は、一般式ＳｉＸ₄で表され、Ｘはハロゲン、メトキシ基、エトキシ基、またはアセチル基等であるケイ素化合物、それらの加水分解物であるシラノール、または平均分子量３０００以下のポリシロキサンが好ましい。
【００９０】
具体的には、テトラエトキシシラン、テトライソプロポキシシラン、テトラ−ｎ−プロポキシシラン、テトラブトキシシラン、テトラメトキシシラン等が挙げられる。また、この場合には、無定形シリカの前駆体と光触媒の粒子とを非水性溶媒中に均一に分散させ、基板上に空気中の水分により加水分解させてシラノールを形成させた後、常温で脱水縮重合することにより光触媒含有層を形成できる。シラノールの脱水縮重合を１００℃以上で行えば、シラノールの重合度が増し、膜表面の強度を向上できる。また、これらの結着剤は、単独あるいは２種以上を混合して用いることができる。
【００９１】
光触媒含有層中の光触媒の含有量は、５〜６０重量％、好ましくは２０〜４０重量％の範囲で設定することができる。また、光触媒含有層の厚みは、０．０５〜１０μｍの範囲内が好ましい。
【００９２】
さらに、光触媒含有層には上記の光触媒、バインダの他にも、濡れ性変化層に添加できるような各種の界面活性剤、樹脂、樹脂以外のポリマー、オリゴマー等を添加することができる。
【００９３】
（パターン形成体の製造）
所定の基板の表面に、本発明の濡れ性変化皮膜を形成し、所定のパターン状に光を照射すると、露光部位が高親水性になり、露光部位と非露光部位の間にパターン形成用材料に対する濡れ性の差が生じる。そこで、露光部位又は非露光部位に対して適切な濡れ性を有するパターン形成用材料を、インクジェットなどの方法で皮膜表面（基板表面）に供給すると、露光部位又は非露光部位にパターン形成用材料を選択的に付着させることができ、所望のパターンが形成される。
【００９４】
濡れ性変化皮膜を露光する際には、濡れ性変化皮膜の上方から光を照射してもよいし、或いは、基板の光線透過率が高い場合には基板側から光を照射してもよい。
【００９５】
本発明において用いられる光触媒は、そのバンドギャップによって触媒反応を開始する光の波長が異なる。例えば、硫化カドニウムであれば４９６ｎｍ、また酸化鉄であれば５３９ｎｍの可視光であり、二酸化チタンであれば３８８ｎｍの紫外光である。したがって、用いる光触媒に合わせて、適切な波長の光線を用いてパターン状露光を行う。光触媒として二酸化チタンを用いる場合には、光線中に４００ｎｍ以下の範囲、好ましくは３８０ｎｍ以下の範囲の紫外成分が含まれることが好ましい。このような紫外光を含む光の光源としては、水銀ランプ、メタルハライドランプ、キセノンランプ、エキシマランプ等の種々の紫外線光源を挙げることができる。
【００９６】
露光した濡れ性変化皮膜の表面に、露光パターン又はそのネガパターンに合わせて選択的に付着させるパターン形成用材料としては、用途に応じて、インキその他の塗工材料を使用することができる。本発明の濡れ性変化皮膜に光を照射すると、得られる露光部位は、２０〜５０ｍＮ／ｍの表面張力を有するインキに対して良好な濡れ性を示す親インキ性領域となる。一方、濡れ性変化皮膜の非露光部位は、光照射を行う前と変わらず撥インキ性領域のままである。ここで、親インキ性領域とは、インキとの接触角が小さい領域であり、一般的な印刷インキ、インクジェット用インキ、カラーフィルターの着色層用或いはブラックマトリックス用インキ、又は、マイクロレンズ形成用組成物等に対する濡れ性の良好な領域をいうこととする。また、撥インキ性領域とは、インキとの接触角が大きい領域領域であり、上記インキに対する濡れ性が悪い領域をいうこととする。
【００９７】
従って、本発明の濡れ性変化皮膜を所定のパターン状に露光し、露光部に２０〜５０ｍＮ／ｍの表面張力を有するインキをインクジェット等の方法により選択的に付着させることにより、高精細で白抜けのないパターンが得られる。
【００９８】
特に好適には、本発明の濡れ性変化皮膜は、カラーディスプレーに用いられるカラーフィルターの画素部（着色層）やブラックマトリックス層を形成するのに用いられる。すなわち、石英ガラス、パイレックスガラス、合成石英板、透明樹脂板等の透明基板を準備し、当該透明基板の表面に、光触媒を含有する濡れ性変化層を形成するか、又は、光触媒含有層と濡れ性変化層とを順次形成することにより、本発明の濡れ性変化皮膜を設ける。次に、当該濡れ性変化皮膜の表面に、フォトマスクを介して光を照射したり、或いは、レーザーで描画することにより、所定のパターン状に露光する。そして、高親水性にされた露光部位にブラックマトリックス用インキ又は着色層用インキをインクジェット等の方法で選択的に付着させてブラックマトリックス層又は着色層を形成し、その後、同じ濡れ性変化皮膜の上に、パターン状の露光とブラックマトリックス用インキ又は着色層用インキの選択的付着を繰り返す。このような方法によって、基板上に各色の着色層とブラックマトリックス層を順次形成し、高精細で、白抜けのないカラーフィルターを効率よく製造することができる。
【００９９】
【実施例】
（実施例１）
３ｇのイソプロピルアルコール、０．０２０ｇのフルオロアルキルシラン（トーケムプロダクツ製ＭＦ−１６０Ｅ：Ｎ−［３−（トリメトキシシリル）プロピル］−Ｎエチルパーフルオロオクタンスルホンアミドのイソプロピルエーテル５０重量％溶液）、２ｇのアルコキシシラン含有酸化チタンゾル無機コーティング剤（石原産業製ＳＴ−Ｋ０３）、４ｇの２規定塩酸水を混合した。得られた混合液は、合計０．０００５モルの加水分解縮合可能な珪素化合物（フルオロアルキルシランとアルコキシシラン）及び０．２３モルの水を含有し、ｐＨ１だった。この混合液を、１００℃で１２０分間攪拌した。
【０１００】
得られた反応液を、厚さ０．７ｍｍの無アルカリガラス基板上にスピンコーティング法によりコートし、厚さ０．１５μｍの光触媒含有膜を得た。
【０１０１】
この光触媒含有膜表面の濡れ標準試薬（３１、４０、４７、５６ｍＮ／ｍ）及び水に対する接触角を、接触角測定器（協和界面科学製ＣＡ−Ｚ型）により測定し、その実測値を用いてジスマンプロットを行ったグラフを、図１にグラフａとして示す。
【０１０２】
また、この光触媒含有膜表面に格子状のフォトマスクを介して超高圧水銀ランプにより１５ｍＷ／ｃｍ²（２５４ｎｍ）の照度で紫外線照射を行い、水に対する接触角が０度になるまでに要した時間を表１に示す。
【０１０３】
【表１】

【０１０４】
（比較例１）
３ｇのイソプロピルアルコール、０．０３０ｇのフルオロアルキルシラン（トーケムプロダクツ製ＭＦ−１６０Ｅ：Ｎ−［３−（トリメトキシシリル）プロピル］−Ｎエチルパーフルオロオクタンスルホンアミドのイソプロピルエーテル５０重量％溶液）、２ｇの酸化チタンゾル（石原産業製ＳＴＳ−０１）を混合し、１００℃で２０分間攪拌した。この溶液に、シリカゾルであるグラスカＨＰＣ７００２（日本合成ゴム製）０．６ｇ、アルキルアルコキシシランであるＨＰＣ４０２Ｈ（日本合成ゴム製）０．２ｇを混合した。得られた混合液は、合計０．００１５モルの加水分解縮合可能な珪素化合物（フルオロアルキルシランとアルキルアルコキシシラン）及び０．０９５モルの水を含有し、ｐＨ１．９だった。この混合液を、２５℃で２０分間攪拌した。
【０１０５】
得られた反応液を、厚さ０．７ｍｍの無アルカリガラス基板上にスピンコーティング法によりコートし、厚さ０．１５μｍの光触媒含有膜を得た。
【０１０６】
この光触媒含有膜表面の濡れ標準試薬（３１、４０、４７、５６ｍＮ／ｍ）に対する接触角を、接触角測定器（協和界面科学製ＣＡ−Ｚ型）により測定し、その実測値を用いてジスマンプロットを行ったグラフを、図１にグラフｂとして示す。
【０１０７】
また、この光触媒含有膜表面に格子状のフォトマスクを介して超高圧水銀ランプにより１５ｍＷ／ｃｍ²（２５４ｎｍ）の照度で紫外線照射を行い、水に対する接触角が０度になるまでに要した時間を表１に示す。
【０１０８】
（比較例２）
３ｇのイソプロピルアルコール、０．０３０ｇのフルオロアルキルシラン（トーケムプロダクツ製ＭＦ−１６０Ｅ：Ｎ−［３−（トリメトキシシリル）プロピル］−Ｎエチルパーフルオロオクタンスルホンアミドのイソプロピルエーテル５０重量％溶液）、２ｇの酸化チタンゾル（石原産業製ＳＴＳ−０１）、シリカゾルであるグラスカＨＰＣ７００２（日本合成ゴム製）０．６ｇ、アルキルアルコキシシランであるＨＰＣ４０２Ｈ（日本合成ゴム製）０．２ｇを混合した。得られた混合液は、合計０．００１５モルの加水分解縮合可能な珪素化合物（フルオロアルキルシランとアルキルアルコキシシラン）及び０．０９５モルの水を含有し、ｐＨ１．９だった。この混合液を、１００℃で２０分間攪拌した。
【０１０９】
得られた反応液を、厚さ０．７ｍｍの無アルカリガラス基板上にスピンコーティング法によりコートし、厚さ０．１５μｍの光触媒含有膜を得た。
【０１１０】
この光触媒含有膜表面の濡れ標準試薬（３１、４０、４７、５６ｍＮ／ｍ）に対する接触角を、接触角測定器（協和界面科学製ＣＡ−Ｚ型）により測定し、その実測値を用いてジスマンプロットを行ったグラフを、図１にグラフｃとして示す。
【０１１１】
また、この光触媒含有膜表面に格子状のフォトマスクを介して超高圧水銀ランプにより１５ｍＷ／ｃｍ²（２５４ｎｍ）の照度で紫外線照射を行い、水に対する接触角が０度になるまでに要した時間を表１に示す。
【０１１２】
（比較例３）
３ｇのイソプロピルアルコール、０．０３０ｇのフルオロアルキルシラン（トーケムプロダクツ製ＭＦ−１６０Ｅ：Ｎ−［３−（トリメトキシシリル）プロピル］−Ｎエチルパーフルオロオクタンスルホンアミドのイソプロピルエーテル５０重量％溶液）、２ｇの酸化チタンゾル（石原産業製ＳＴＳ−０１）、シリカゾルであるグラスカＨＰＣ７００２（日本合成ゴム製）０．３ｇ、アルキルアルコキシシランであるＨＰＣ４０２Ｈ（日本合成ゴム製）０．１ｇを混合した。得られた混合液は、合計０．０００７５モルの加水分解縮合可能な珪素化合物（フルオロアルキルシランとアルキルアルコキシシラン）及び０．０８６モルの水を含有し、ｐＨ１．８だった。この混合液を、１００℃で２０分間攪拌した。
【０１１３】
得られた反応液を、厚さ０．７ｍｍの無アルカリガラス基板上にスピンコーティング法によりコートし、厚さ０．１５μｍの光触媒含有膜を得た。
【０１１４】
この光触媒含有膜表面の濡れ標準試薬（３１、４０、４７、５６ｍＮ／ｍ）に対する接触角を、接触角測定器（協和界面科学製ＣＡ−Ｚ型）により測定し、その実測値を用いてジスマンプロットを行ったグラフを、図１にグラフｄとして示す。
【０１１５】
また、この光触媒含有膜表面に格子状のフォトマスクを介して超高圧水銀ランプにより１５ｍＷ／ｃｍ²（２５４ｎｍ）の照度で紫外線照射を行い、水に対する接触角が０度になるまでに要した時間を表１に示す。
【０１１６】
（比較例４）
３ｇのイソプロピルアルコール、０．０２０ｇのフルオロアルキルシラン（トーケムプロダクツ製ＭＦ−１６０Ｅ：Ｎ−［３−（トリメトキシシリル）プロピル］−Ｎエチルパーフルオロオクタンスルホンアミドのイソプロピルエーテル５０重量％溶液）、２ｇのアルコキシシラン含有酸化チタンゾル無機コーティング剤（石原産業製ＳＴ−Ｋ０３）を混合した。得られた混合液には、合計０．０００５モルの加水分解縮合可能な珪素化合物（フルオロアルキルシランとアルコキシシラン）及び０．０５６モルの水を含有し、ｐＨ１．９だった。この混合液を、１００℃で２０分間攪拌した。
【０１１７】
得られた反応液を、厚さ０．７ｍｍの無アルカリガラス基板上にスピンコーティング法によりコートし、厚さ０．１５μｍの光触媒含有膜を得た。
【０１１８】
この光触媒含有膜表面の濡れ標準試薬（３１、４０、４７、５６ｍＮ／ｍ）及び水に対する接触角を、接触角測定器（協和界面科学製ＣＡ−Ｚ型）により測定し、その実測値を用いてジスマンプロットを行ったグラフを、図１にグラフｅとして示す。
【０１１９】
また、この光触媒含有膜表面に格子状のフォトマスクを介して超高圧水銀ランプにより１５ｍＷ／ｃｍ²（２５４ｎｍ）の照度で紫外線照射を行い、水に対する接触角が０度になるまでに要した時間を表１に示す。
【０１２０】
【発明の効果】
以上説明したように、本発明によれば、所定基板の表面を被覆し、光照射前には高撥水性を示し、光照射によって速やかに高親水性化する濡れ性変化皮膜、及び、そのような濡れ性変化皮膜を形成するのに好適な光触媒含有組成物が提供される。この濡れ性変化皮膜の表面を所定のパターン状に露光すると、露光部と非露光部の間にパターン形成用材料に対する濡れ性の差を十分に大きくとることができると共に、少ない露光量でも短時間のうちに濡れ性の差を大きくすることができる。従って、露光部と非露光部の間に濡れ性の大きな差があることを利用して、露光部又は非露光部にパターン形成用材料を選択的に付着させることができ、基板上に高精細で白抜けのないパターンを形成することができる。しかも、本発明の濡れ性変化皮膜は感度が高いので、露光工程の時間を極めて短くすることができ、生産性が高い。
【０１２１】
さらに、本発明の濡れ性変化皮膜及び光触媒含有組成物を用いることにより、カラー液晶ディスプレー用の、高精細で白抜けのないカラーフィルターを効率よく製造することができる。
【０１２２】
さらに、上記したような特性を有する濡れ性変化層を作製するための濡れ性変化層用組成物は、フルオロアルキル基を含有する珪素化合物の１種又は２種以上を、酸と水の存在下で加水分解縮合又は共加水分解縮合させることによって調製することができる。
【図面の簡単な説明】
【図１】本発明の濡れ性変化皮膜の特性を説明するためのジスマンプロットである。グラフ中のａは本発明の濡れ性変化皮膜を示し、ｂ〜ｅは本発明には属さない濡れ性変化皮膜を示す。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wettability changing film that coats the surface of a predetermined substrate and is hydrophilized by a photocatalytic reaction on the surface of the substrate, and wettability to a pattern forming material between an exposed portion and a non-exposed portion on the substrate surface. The pattern forming material can be selectively and accurately attached to a desired portion of the substrate surface, and the sensitivity is good. Even with a small amount of exposure, the difference in wettability can be achieved in a short time. It relates to a wettability change film in which the value of the film increases. The present invention also relates to a composition for forming such a photocatalytic-reactive wettability changing film.
[0002]
In particular, the present invention relates to a wettability changing film suitable for patterning a pixel portion (colored layer) or a black matrix of a color filter used for a color liquid crystal display, and a composition for forming the film.
[0003]
[Prior art]
In recent years, with the development of personal computers, particularly with the development of portable personal computers, the demand for liquid crystal displays, especially color liquid crystal displays, has been increasing. However, since this color liquid crystal display is expensive, there is an increasing demand for cost reduction, and in particular, there is a high demand for cost reduction for a color filter having high specific gravity.
[0004]
Such a color filter usually has a coloring pattern of three primary colors of red (R), green (G), and blue (B), and the electrodes corresponding to the R, G, and B pixels are turned on. By turning it off, the liquid crystal operates as a shutter, and light passes through each of the R, G, and B pixels, and color display is performed.
[0005]
As a conventional method for producing a color filter, for example, a staining method can be mentioned. In this dyeing method, first, a water-soluble polymer material, which is a dyeing material, is formed on a glass substrate, patterned into a desired shape by a photolithography process, and then the obtained pattern is immersed in a dyeing bath. To get a colored pattern. By repeating this three times, R, G, and B color filter layers are formed.
[0006]
Another method is a pigment dispersion method. In this method, first, a photosensitive resin layer in which a pigment is dispersed is formed on a substrate, and this is patterned to obtain a monochromatic pattern. Further, by repeating this process three times, R, G, and B color filter layers are formed.
[0007]
Still other methods include an electrodeposition method, a method in which a pigment is dispersed in a thermosetting resin, R, G, and B are printed three times, and then the resin is thermoset.
[0008]
[Problems to be solved by the invention]
However, in the conventional dyeing method and pigment dispersion method, it is necessary to repeat the process of applying the photosensitive resin to the transparent substrate by spin coating or the like, and the subsequent development and washing processes for each color pattern formation. Material loss in the process is unavoidable, it is difficult to simplify the process, and it is difficult to reduce the manufacturing cost. In addition, it is difficult to form a high-definition pattern by the printing method, and there is a problem that a pattern shape that can be formed by the electrodeposition method is limited.
[0009]
In order to solve such problems, the present inventors formed a photocatalyst-containing layer containing a photocatalyst and an organopolysiloxane as a binder on a transparent substrate, and the photocatalyst-containing layer has a predetermined pattern shape. To make the exposed area highly hydrophilic, and selectively apply black matrix ink or colored layer ink to the highly hydrophilic exposed area to form a black matrix layer or colored layer, then containing the same photocatalyst A method of manufacturing a color filter having a colored layer and a black matrix layer for each color was developed by repeating pattern exposure and selective deposition of black matrix ink or colored layer ink on the layer. , Keep improving.
[0010]
According to this method, since the coating process for forming the photocatalyst-containing layer is only required once, the loss of the coating material can be reduced and the coating process can be simplified. Further, according to this method, the pattern forming material (black matrix ink or colored layer ink) can be selectively attached to the exposed portion, so that the development and washing steps after exposure can be omitted. . Therefore, it is possible to obtain a color filter with high production efficiency and high definition and free from defects such as white spots.
[0011]
However, in order to further improve the production efficiency of the color filter, high hydrophilicity by exposure proceeds rapidly, and a sufficient difference in wettability occurs between the exposed and unexposed areas within a short time. In addition, it is necessary to increase the exposure sensitivity of the photocatalyst-containing layer.
[0012]
One way to increase the sensitivity of the photocatalyst-containing layer is to reduce the amount of water-repellent atoms or water-repellent atomic groups such as alkyl groups present in the molecular structure of the binder contained in the photocatalyst-containing layer. . For example, the sensitivity can be increased by reducing the alkyl group content of the organopolysiloxane contained in the photocatalyst containing layer. However, if the water-repellent atoms or water-repellent atomic groups in the binder are reduced, the water repellency of the photocatalyst-containing layer is already low before exposure, so wettability to the pattern forming material between the exposed and non-exposed areas. Therefore, the selective adhesion of the pattern forming material to the exposed portion is deteriorated. As a result, there arises a problem that the fineness of the pattern of the colored layer or the black matrix layer is not sufficiently increased, and white spots of the colored layer are likely to occur.
[0013]
The present invention has been accomplished in view of the above-described actual situation. The first object of the present invention is to coat the surface of a predetermined substrate and make it hydrophilic by photocatalytic reaction on the surface of the substrate. Providing a wettability-changing film that can sufficiently increase the difference in wettability with respect to the pattern forming material between the non-exposed portion and the non-exposed portion, and that increases the wettability difference in a short time even with a small exposure amount. It is in.
[0014]
A second object of the present invention is to provide a coating composition suitable for forming such a photocatalytic-reactive wettability changing film.
[0015]
The third object of the present invention is to provide a suitable method for producing a coating composition for forming the wettability changing film.
[0016]
Furthermore, a fourth object of the present invention is to form a wettability changing film suitable for patterning a pixel portion (colored layer) or a black matrix of a color filter used in a color liquid crystal display, and the film. An object of the present invention is to provide a coating composition.
[0017]
[Means for Solving the Problems]
The photocatalyst-containing composition provided in the present invention is a photocatalyst-containing composition for forming a wettability changing film that becomes hydrophilic by a photocatalytic reaction,
The photocatalyst-containing composition contains at least a binder and a photocatalyst,
A contact angle (θ) is obtained by bringing a droplet of a wet standard reagent formed by mixing formamide and ethylene glycol monoethyl ether into contact with the surface of a film that has been formed using the photocatalyst-containing composition and has not yet been hydrophilized. When measuring and creating a Zisman plot graph,
The contact angle (θ) measured or determined by the Zisman plot of the wet standard reagent shows 30 degrees or more in all or part of the range of the surface tension of 20 to 50 mN / m, and
Following formula
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) is 0 in the range where the surface tension is 20 to 50 mN / m. 0.02 or less.
[0018]
The wettability changing film of the present invention having a wettability changing layer containing a photocatalyst can be formed by applying the photocatalyst-containing composition to the surface of a predetermined substrate and drying or curing the composition.
[0019]
In a preferred embodiment, the photocatalyst-containing composition of the present invention comprises, as a binder, a hydrolyzable silicon compound, or a reaction product obtained by hydrolyzing and / or condensing at least a part of the hydrolysable silicon compound. contains.
[0020]
It is preferable that at least a part of the silicon compound capable of hydrolytic condensation has a fluoroalkyl group.
[0021]
The silicon compound capable of hydrolysis condensation is Y_nSiX_(4-n)(Y represents hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule may be the same or different from each other. X represents an alkoxyl group, an acetyl group or a halogen. A plurality of X in one molecule may be the same or different from each other, n is an integer of 0 to 3), and It is particularly preferred that at least a part thereof has a fluoroalkyl group.
[0022]
The wettability changing film provided in the present invention is a wettability changing film that coats a predetermined substrate surface and is hydrophilized by a photocatalytic reaction,
The wettability changing film includes a wettability changing layer that is hydrophilized by a photocatalytic reaction, and a photocatalytic system that causes the photocatalytic reaction of the wettability changing layer.
The surface of the wettability change layer that has not yet been hydrophilized is brought into contact with a wet standard reagent droplet formed by mixing formamide and ethylene glycol monoethyl ether, and the contact angle (θ) is measured. When creating a graph,
The contact angle (θ) measured using the wetting standard reagent or determined by the Zisman plot shows 30 degrees or more in all or part of the surface tension range of 20 to 50 mN / m, and ,
Following formula
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) is 0 in the range where the surface tension is 20 to 50 mN / m. 0.02 or less.
[0023]
The photocatalyst system may be present in the wettability changing layer or may be independent of the wettability changing layer. For example, the wettability changing film of the present invention may be provided with the wettability changing layer containing a photocatalyst, or provided on a photocatalyst containing layer containing a photocatalyst and the photocatalyst containing layer. The wettability changing layer may be provided.
[0024]
In the present invention, when a wetting standard reagent droplet is brought into contact with the surface of the wettability changing layer, the contact angle measured using the wetting standard reagent or a Zisman plot graph based on the measured value is determined. The contact angle is 30 degrees or more in all or part of the surface tension range of 20 to 50 mN / m. Various inks used in various fields usually have a surface tension of 20 to 50 mN / m. Therefore, when the non-exposed portion of the wettability changing layer exhibits a contact angle of 30 ° or more with respect to the surface tension in this range, the ink repellency of the non-exposed portion is sufficient, and as a result, hydrophilicity ( The difference in wettability with respect to the ink for pattern formation can be made large between the exposed portion of (ink affinity) and the non-exposed portion of ink repellency.
[0025]
Furthermore, the wettability changing layer of the wettability changing film belonging to the present invention measures the contact angle (θ) by bringing the above-mentioned wetness standard reagent droplets into contact with the surface of the wettability changing layer that has not yet been made hydrophilic. Then, a graph of the Zisman plot is created, and a cosine value (cos θ) is derived from the contact angle (θ) actually measured using the wet standard reagent or the contact angle (θ) determined by the Zisman plot. The average reduction rate (X) of the value (cos θ) is expressed by the following formula:
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
When the surface tension is in the range of 20 to 50 mN / m, the absolute value (| X |) of the calculated average decrease rate (X) is 0.02 or less.
[0026]
When the absolute value (| X |) of the average reduction rate (X) of cos θ is larger than 0.02, the exposure sensitivity of the wettability changing layer is about the conventional level, and high hydrophilicity by light irradiation is reduced for a short time. It is difficult to complete in a short time. On the other hand, when the absolute value (| X |) of the average reduction rate (X) of cos θ is 0.02 or less, the exposure sensitivity of the wettability changing layer is high, and the exposure amount is small and the time is short. Highly hydrophilic. It is not clear why the exposure sensitivity of the wettability changing layer is improved when the average reduction rate (X) of the cosine value (cos θ) of the contact angle is small. However, the critical surface tension of the wettability changing layer is probably small and repellent. Even when water-based (ink repellency) is high, if the average reduction rate (X) of the cosine value (cos θ) of the contact angle is small, the contact angle of the water droplet does not increase so much, so a relatively large amount of physically adsorbed water is retained. It is speculated that the photocatalytic reaction is promoted by the physically adsorbed water.
[0027]
When the surface of a predetermined substrate is coated using such a wettability changing film of the present invention, it exhibits high water repellency before light irradiation and quickly becomes highly hydrophilic by light irradiation. When the surface of this wettability changing film is exposed in a predetermined pattern, the difference in wettability with respect to the pattern forming material can be sufficiently large between the exposed portion and the non-exposed portion, and even with a small exposure amount. The difference in wettability can be increased within a short time. Therefore, by utilizing the fact that there is a large difference in wettability between the exposed part and the non-exposed part, the pattern forming material can be selectively attached to the exposed part or the non-exposed part. Thus, a pattern without white spots can be formed. Moreover, since the wettability changing film of the present invention has high sensitivity and quickly becomes highly hydrophilic, the exposure process time can be extremely shortened and the productivity is high.
[0028]
Furthermore, by using the wettability changing film and the photocatalyst-containing composition of the present invention, it is possible to efficiently produce a color filter for color liquid crystal displays that does not have white spots.
[0029]
In the present invention, it is preferable that a critical surface tension of the wettability changing layer that has not been hydrophilized is 40 mN / m or less when the wet standard reagent is used.
[0030]
In the present invention, it is preferable that the surface of the wettability changing layer that has not been hydrophilized yet exhibits a contact angle (θ) of 80 degrees or less with respect to water.
[0031]
The method for producing a wettability changing resin composition provided in the present invention is characterized by hydrolyzing and condensing a fluoroalkyl group-containing silicon compound in the presence of an acid and water.
[0032]
As the fluoroalkyl group-containing silicon compound, the following general formula
Y_pSiX_(4-p)
(Y represents hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule may be the same or different from each other, provided that at least one Y is fluoroalkyl. A hydrocarbon group having a group or a fluoroalkyl group, X represents an alkoxyl group, an acetyl group or a halogen, a plurality of X in one molecule may be the same or different from each other, and p is from 1 to 3 Is an integer.)
It is preferable to use a fluoroalkyl group-containing silicon compound represented by the formula:
[0033]
Further, the above water and acid are added to a reaction system containing a fluoroalkyl group-containing silicon compound, and the total of the fluoroalkyl group-containing silicon compound and other hydrolytic condensation-consumable silicon compounds added as necessary. It is preferable to perform hydrolysis and condensation by adjusting the ratio of water to the amount to 200 times or more in terms of molar ratio and adjusting the pH of the reaction system to 2 or less.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
The wettability changing film according to the present invention includes a wettability changing layer that becomes hydrophilic by a photocatalytic reaction, and a photocatalytic system that causes a photocatalytic reaction of the wettability changing layer. The photocatalytic system may be in any state or in any positional relationship as long as it coexists in a state capable of causing the photocatalytic reaction of the wettability changing layer. For example, a photocatalyst can be contained in the wettability changing layer. Alternatively, a photocatalyst-containing layer may be provided independently of the wettability changing layer, and the wettability changing layer may be formed thereon.
[0035]
(Wettability change layer)
In the wettability changing film of the present invention, a wet standard reagent droplet formed by mixing formamide and ethylene glycol monoethyl ether is brought into contact with the surface of the wettability changing layer that has not yet been hydrophilized by the photocatalytic reaction. Measure the contact angle (θ) and create a Zisman plot graph.
The actually measured contact angle (θ) of the wet standard reagent or the contact angle (θ) determined by the Zisman plot is 30 degrees or more in all or part of the range where the surface tension is 20 to 50 mN / m. Show and
The average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) is expressed by the following formula:
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the calculated average reduction rate (X) is 0.02 or less when the surface tension is in the range of 20 to 50 mN / m.
[0036]
Here, the above-mentioned wetting standard reagent is prepared according to JIS K 6768. However, the contact angle of the water droplet may be measured at the final measurement point near 72 to 73 mN / m. Further, in the present invention, the contact angle refers to a contact angle measuring instrument (for example, CA-Z type manufactured by Kyowa Interface Science Co., Ltd.) 30 seconds after dropping a droplet or water droplet of a wet standard reagent from a microsyringe. The measured values and the contact angles actually measured at a plurality of points of the surface tension are plotted on a later-described Zisman plot to create a graph, and the contact angles at each surface tension determined using this graph are referred to.
[0037]
Such features of the present invention will be described with reference to a Zisman plot in FIG. In the Zisman plot, the surface of a test sample is contacted with a droplet of a wet standard reagent having a predetermined surface tension, the contact angle (θ) is measured, the surface tension of the wet standard reagent is taken on the horizontal axis, It is the graph which plotted the contact angle ((theta)) measured in each surface tension or its cosine value (cos (theta)) on the vertical axis | shaft.
[0038]
1 shows an example (a) of a wettability change film belonging to the present invention and four wettability change films (b, c, d, and the like) developed by the present inventors before the present invention. Using e) as a test sample, a contact angle (θ) is measured by bringing a wet standard reagent droplet formed by mixing formamide and ethylene glycol monoethyl ether into contact, and the contact angle (θ) at each surface tension and its cosine are measured. The values (cos θ) are plotted. Each film sample is a single layer film formed by mixing a photocatalyst with a binder, that is, a wettability changing layer containing a photocatalyst.
[0039]
When a contact angle is measured by bringing a droplet of a wet standard reagent into contact with the surface of the wettability changing layer belonging to the present invention and a Zisman plot graph is created, the measured contact angle (θ) or Zisman plot is determined. The contact angle (θ) is a contact angle of 30 degrees or more in all or part of the range where the surface tension is 20 to 50 mN / m, as indicated by a in FIG. This contact angle preferably represents 30 degrees or more in the whole or part of the range of 20 to 40 mN / m, and particularly preferably 30 degrees or more in the whole or part of the range of 25 to 35 mN / m. Furthermore, this contact angle most preferably exhibits a contact angle of 30 degrees or more in the entire range of 20 to 50 mN / m.
[0040]
Various inks used in various fields, for example, ink for forming a colored layer of a color filter, ink for forming a black matrix layer, and general printing ink are usually 20 to 50 mN / m. Many have a surface tension of 20 to 40 mN / m, and many have a surface tension of 25 to 35 mN / m. Therefore, when the non-exposed portion of the wettability changing layer exhibits a contact angle of 30 degrees or more with respect to the liquid having the surface tension in this range, the ink repellency of the non-exposed portion is sufficient. The difference in wettability with respect to the pattern forming ink can be increased between the hydrophilic (ink-philic) exposed portion and the ink-repellent non-exposed portion.
[0041]
Further, the surface tension when the contact angle (θ) is 0 (zero) or cos θ is 1 in the Zisman plot of FIG. 1 is called critical surface tension, and the smaller the value, the more water-repellent (ink-repellent). High). Therefore, when the critical surface tension of the wettability changing layer that has not been hydrophilized before exposure is 40 mN / m or less, the ink repellency of the non-exposed portion is extremely high, which is preferable.
[0042]
As described above, the wettability changing layer of the wettability changing film belonging to the present invention has a characteristic that the contact angle becomes 30 degrees or more in all or a part of the surface tension in the range of 20 to 50 mN / m. In addition to this, the wettability changing layer of the wettability changing film belonging to the present invention is brought into contact with the surface of the wettability changing layer that has not been hydrophilized yet by bringing the droplet of the wet standard reagent into contact with the contact angle (θ ) Is measured to create a Zisman plot graph, and the average decrease rate of the cosine value (cos θ) derived from the actually measured contact angle (θ) or the contact angle (θ) determined by the Zisman plot It also has a characteristic that the absolute value (| X |) of (X) is very small. That is, in the present invention, the wettability changing layer has an average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) by the following formula:
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the average reduction rate (X) calculated in the range of 20 to 50 mN / m of the surface tension is 0.02 or less. This average reduction rate (X) means the slope of the line obtained by plotting in the Zisman plot of FIG. As apparent from FIG. 1, the wettability changing layer a of the wettability changing film belonging to the present invention has an average reduction rate (X) of cos θ as compared with the other wettability changing layers b, c, d, and e. The absolute value (| X |) is very small, and the slope on the graph is gentle.
[0043]
When the absolute value (| X |) of the average reduction rate (X) of cos θ is larger than 0.02, the exposure sensitivity of the wettability changing layer is about the conventional level, and high hydrophilicity by light irradiation is reduced for a short time. It is difficult to complete in a short time. It is not clear why the exposure sensitivity of the wettability changing layer is improved when the average reduction rate (X) of the cosine value (cos θ) of the contact angle is small. However, the critical surface tension of the wettability changing layer is probably small and repellent. Even when water-based (ink repellency) is high, if the average reduction rate (X) of the cosine value (cos θ) of the contact angle is small, the contact angle of the water droplet does not increase so much, so a relatively large amount of physically adsorbed water is retained. It is speculated that the photocatalytic reaction is promoted by the physically adsorbed water. As a result, it is presumed that the difference in wettability with respect to ink between the exposed portion and the non-exposed portion can be made large, and the light irradiation process can be completed in a short time.
[0044]
Further, when the wettability changing layer has a sufficiently low critical surface tension and the absolute value (| X |) of the average reduction rate (X) of cos θ is 0.02 or less, the contact angle of water droplets However, compared with the conventional wettability change layer, the contact angle of water drops is 80 degrees or less.
[0045]
The material used for such a wettability changing layer is a material that changes its wettability by being hydrophilized by a photocatalytic reaction, and has a high binding energy that does not cause deterioration or degradation of the main chain due to photoexcitation of the photocatalyst. Among those possessed, those having the above-mentioned characteristics are selected when formed into a film.
[0046]
For example, (1) an organopolysiloxane compound that exhibits high strength by hydrolyzing and polycondensing chloro or alkoxysilane by sol-gel reaction or the like, and (2) a reactive silicone having excellent water and oil repellency is crosslinked. Examples thereof include organopolysiloxane compounds.
[0047]
In the case of (1) above, the general formula:
Y_nSiX_(4-n)
(Here, Y represents hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule may be the same as or different from each other. X represents an alkoxyl group, acetyl. Represents a group or halogen, and a plurality of X in one molecule may be the same or different from each other, and n is an integer of 0 to 3.)
It is preferable that it is the organopolysiloxane which is a 1 type, or 2 or more types of hydrolytic condensate or cohydrolysis condensate of the silicon compound represented by these.
[0048]
The silicon compound represented by the above general formula preferably has at least one hydrocarbon group which may have a substituent as Y.
[0049]
In the above general formula, the unsubstituted hydrocarbon group or the hydrocarbon group portion of the substituted hydrocarbon group may be, for example, a linear or branched aliphatic hydrocarbon group such as methyl, ethyl or other alkyl; cyclohexyl, etc. An unsaturated hydrocarbon group such as vinyl; an aromatic hydrocarbon group such as phenyl, etc., and the carbon number of these hydrocarbon group or hydrocarbon group moiety is in the range of 1 to 20 It is preferable that
[0050]
In the above general formula, the hydrocarbon group which may have a substituent includes a fluorine-containing hydrocarbon group such as fluoroalkyl; glycidoxyalkyl and β- (3,4-epoxycyclohexyl) alkyl. Epoxy-containing hydrocarbon groups; acryloyloxy or methacryloyloxy-containing hydrocarbon groups such as (meth) acryloyloxyalkyl; amino-containing hydrocarbon groups such as aminoalkyl; mercapto-containing hydrocarbon groups such as mercaptoalkyl; N-fluoro Examples thereof include fluoroalkyl-containing hydrocarbon groups including N-fluoroalkylsulfonamide group-containing hydrocarbon groups such as alkylsulfonylaminoalkyl.
[0051]
The alkoxy group represented by X is preferably a methoxy group, an ethoxy group, a propoxy group, or a butoxy group.
[0052]
Specifically, methyltrichlorosilane, methyltribromosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltrit-butoxysilane; ethyltrichlorosilane, ethyltribromosilane, ethyltrimethoxysilane, Ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltri-t-butoxysilane; n-propyltrichlorosilane, n-propyltribromosilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltriisopropoxy Silane, n-propyltri-t-butoxysilane; n-hexyltrichlorosilane, n-hexyltribromosilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-hexyl Lutriisopropoxysilane, n-hexyltri-t-butoxysilane; n-decyltrichlorosilane, n-decyltribromosilane, n-decyltrimethoxysilane, n-decyltriethoxysilane, n-decyltriisopropoxysilane, n -Decyltri-t-butoxysilane; n-octadecyltrichlorosilane, n-octadecyltribromosilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane, n-octadecyltriisopropoxysilane, n-octadecyltri-t-butoxysilane Phenyltrichlorosilane, phenyltribromosilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, phenyltri-t-butoxysilane; tetrachlorosilane Tetrabromosilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane; dimethyldichlorosilane, dimethyldibromosilane, dimethyldimethoxysilane, dimethyldiethoxysilane; diphenyldichlorosilane, diphenyldibromosilane, Diphenyldimethoxysilane, diphenyldiethoxysilane; phenylmethyldichlorosilane, phenylmethyldibromosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane;
Trichlorohydrosilane, tribromohydrosilane, trimethoxyhydrosilane, triethoxyhydrosilane, triisopropoxyhydrosilane, tri-t-butoxyhydrosilane; vinyltrichlorosilane, vinyltribromosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane , Vinyltri-t-butoxysilane; trifluoropropyltrichlorosilane, trifluoropropyltribromosilane, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, trifluoropropyltriisopropoxysilane, trifluoropropyltri-t-butoxysilane Γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropyltrit-butoxysilane; γ-methacryloyloxypropylmethyldimethoxysilane Γ-methacryloyloxypropylmethyldiethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltriethoxysilane, γ-methacryloyloxypropyltriisopropoxysilane, γ-methacryloyloxypropyltri t-butoxysilane; γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxy Sisilane, γ-aminopropyltriisopropoxysilane, γ-aminopropyltri-t-butoxysilane; γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyl Triethoxysilane, γ-mercaptopropyltriisopropoxysilane, γ-mercaptopropyltri-t-butoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltri Ethoxysilanes; and their partial hydrolysates; and mixtures thereof can be used.
[0053]
Further, as the organopolysiloxane compound, those having a fluoroalkyl group are particularly preferable. When a wettability change layer is formed using an organopolysiloxane compound having a fluoroalkyl group, the water repellency and ink repellency of the non-exposed area is enhanced by the action of the fluoroalkyl group, and the exposed area and the high water repellency are made highly hydrophilic. The difference in wettability with respect to the ink can be made large with respect to the non-exposed portion.
[0054]
Specifically, the general formula Y_nSiX_(4-n)Hydrocondensation condensate or co-hydrolysis condensate containing a silicon compound represented by the formula: wherein all or at least part of the condensation unit is a fluoroalkyl group-containing silicon such as the following fluoroalkylsilane What is 1 type or 2 types or more of a compound can be used. The following fluoroalkylsilanes are generally known as fluorine-based silane coupling agents.
[0055]
CF_Three(CF₂)_ThreeCH₂CH₂Si (OCH_Three)_Three;
CF_Three(CF₂)_FiveCH₂CH₂Si (OCH_Three)_Three;
CF_Three(CF₂)₇CH₂CH₂Si (OCH_Three)_Three;
CF_Three(CF₂)₉CH₂CH₂Si (OCH_Three)_Three;
(CF_Three)₂CF (CF₂)_FourCH₂CH₂Si (OCH_Three)_Three;
(CF_Three)₂CF (CF₂)₆CH₂CH₂Si (OCH_Three)_Three;
(CF_Three)₂CF (CF₂)₈CH₂CH₂Si (OCH_Three)_Three;
CF_Three(C₆H_Four) C₂H_FourSi (OCH_Three)_Three;
CF_Three(CF₂)_Three(C₆H_Four) C₂H_FourSi (OCH_Three)_Three;
CF_Three(CF₂)_Five(C₆H_Four) C₂H_FourSi (OCH_Three)_Three;
CF_Three(CF₂)₇(C₆H_Four) C₂H_FourSi (OCH_Three)_Three;
CF_Three(CF₂)_ThreeCH₂CH₂SiCH_Three(OCH_Three)₂;
CF_Three(CF₂)_FiveCH₂CH₂SiCH_Three(OCH_Three)₂;
CF_Three(CF₂)₇CH₂CH₂SiCH_Three(OCH_Three)₂;
CF_Three(CF₂)₉CH₂CH₂SiCH_Three(OCH_Three)₂;
(CF_Three)₂CF (CF₂)_FourCH₂CH₂SiCH_Three(OCH_Three)₂;
(CF_Three)₂CF (CF₂)₆CH₂CH₂Si CH_Three(OCH_Three)₂;
(CF_Three)₂CF (CF₂)₈CH₂CH₂Si CH_Three(OCH_Three)₂;
CF_Three(C₆H_Four) C₂H_FourSiCH_Three(OCH_Three)₂;
CF_Three(CF₂)_Three(C₆H_Four) C₂H_FourSiCH_Three(OCH_Three)₂;
CF_Three(CF₂)_Five(C₆H_Four) C₂H_FourSiCH_Three(OCH_Three)₂;
CF_Three(CF₂)₇(C₆H_Four) C₂H_FourSiCH_Three(OCH_Three)₂;
CF_Three(CF₂)_ThreeCH₂CH₂Si (OCH₂CH_Three)_Three;
CF_Three(CF₂)_FiveCH₂CH₂Si (OCH₂CH_Three)_Three;
CF_Three(CF₂)₇CH₂CH₂Si (OCH₂CH_Three)_Three;
CF_Three(CF₂)₉CH₂CH₂Si (OCH₂CH_Three)_Three;and
CF_Three(CF₂)₇SO₂N (C₂H_Five) C₂H_FourCH₂Si (OCH_Three)_Three.
[0056]
The wettability changing layer containing organopolysiloxane as a binder contains a hydrolyzable silicon compound or a reaction product obtained by hydrolyzing and / or condensing at least a part of the hydrolysable silicon compound. It can form using the resin composition for wettability change layer formation. That is, one or two or more types of silicon compounds that can be hydrolyzed and condensed are mixed with other components such as a photocatalyst as necessary to prepare a coating solution, which is applied onto a substrate or a photocatalyst-containing layer. A wettability change layer containing organopolysiloxane as a binder can be formed by forming a film and drying the film after heating or allowing hydrolysis condensation to proceed or proceeding.
[0057]
Also, at least a part of the silicon compound can be hydrolyzed by hydrolyzing one or more of the silicon compounds that can be condensed units by heating, for example, a liquid mixed with other components such as a photocatalyst. The wettability changing layer can also be prepared by preparing a decomposed and / or condensed reaction solution, applying it on the substrate or the photocatalyst-containing layer, and drying it. Even when a reaction liquid in which at least a part of the silicon compound is hydrolyzed and / or condensed is applied to a substrate or the like, when the coating film is heated and dried, hydrolysis and condensation further proceeds on the substrate to sufficiently Can be condensed.
[0058]
A resin composition for forming a wettability changing layer containing an organopolysiloxane as a binder is prepared in a coating liquid state and applied to a substrate or the like. An appropriate amount of water is blended in the coating solution in order to hydrolyze the silicon compound. Moreover, in order to make the coating to a board | substrate etc. easy, you may dilute the coating liquid of the resin composition for wettability change layers using a suitable solvent.
[0059]
In addition, when it is desired to form a wettability changing layer containing a photocatalyst together with an organopolysiloxane as a binder, the binder component as described above, that is, a silicon compound capable of hydrolytic condensation, or the hydrolytic condensation together with the photocatalyst. A resin composition for forming a wettability changing layer (photocatalyst-containing composition) containing a reaction product obtained by hydrolyzing and / or condensing at least a part of a possible silicon compound is prepared, and the photocatalyst-containing composition is used as a substrate or the like. What is necessary is just to heat and dry the coating film formed and apply | coated on top as needed.
[0060]
In order to form an organopolysiloxane containing a fluoroalkyl group, it is preferable to use a silicon compound having a fluoroalkyl group as the silicon compound capable of being hydrolytically condensed, and when two or more silicon compounds are used in combination. It is preferable that at least a part thereof is a fluoroalkyl group-containing silicon compound.
[0061]
Preferred examples of silicon compounds that can be hydrolytically condensed and contain a fluoroalkyl group include the above-mentioned general formula Y_nSiX_(4-n)(Y represents hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule may be the same or different from each other. X represents an alkoxyl group, an acetyl group or a halogen. A plurality of X in one molecule may be the same or different from each other, n is an integer of 0 to 3, and is composed of one or more silicon compounds represented by: In addition, a simple substance or a mixture of silicon compounds in which at least a part thereof is occupied by a silicon compound having a fluoroalkyl group can be given.
[0062]
Examples of the reactive silicone (2) include compounds having a skeleton represented by the following general formula.
[0063]
[Chemical 1]

[0064]
However, m is an integer greater than or equal to 2, R¹, R²Each represents a substituted or unsubstituted alkyl, alkenyl, aryl or cyanoalkyl group having 1 to 10 carbon atoms, and 40% or less of the total is vinyl, phenyl or phenyl halide in a molar ratio. R¹, R²Is preferably a methyl group because the surface energy becomes the smallest, and the methyl group is preferably 60% or more by molar ratio. In addition, the chain end or side chain has at least one reactive group such as a hydroxyl group in the molecular chain.
[0065]
In addition to the above organopolysiloxane, a stable organosilicon compound that does not undergo a crosslinking reaction, such as dimethylpolysiloxane, may be mixed in the binder.
[0066]
In the present invention, the photocatalyst-containing layer can contain a surfactant in addition to the above-mentioned photocatalyst and binder. Specifically, hydrocarbons such as NIKKOLBL, BC, BO, BB series manufactured by Nikko Chemicals Co., Ltd., ZONYL FSN, FSO manufactured by DuPont, Surflon S-141, 145 manufactured by Asahi Glass Co., Ltd., Dainippon Ink Chemical industry Co., Ltd. MegaFuck F-141, 144, Neos Co., Ltd., Fategent F-200, F251, Daikin Industries Co., Ltd. Unidyne DS-401, 402, 3M Co., Ltd. Fluorado FC-170, Fluorine-based or silicone-based nonionic surfactants such as 176 can be mentioned, and cationic surfactants, anionic surfactants, and amphoteric surfactants can also be used.
[0067]
In addition to the above surfactants, the photocatalyst-containing layer includes polyvinyl alcohol, unsaturated polyester, acrylic resin, polyethylene, diallyl phthalate, ethylene propylene diene monomer, epoxy resin, phenol resin, polyurethane, melamine resin, polycarbonate, Polyvinyl chloride, polyamide, polyimide, styrene butadiene rubber, chloroprene rubber, polypropylene, polybutylene, polystyrene, polyvinyl acetate, polyester, polybutadiene, polybenzimidazole, polyacrylonitrile, epichlorohydrin, polysulfide, polyisoprene, oligomers, polymers, etc. It can be included.
[0068]
In the present invention, the wettability changing layer may contain a photocatalyst. When a photocatalyst is included in the wettability changing layer, a photocatalyst is mixed with an appropriate binder such as the above-described organopolysiloxane compound to prepare a photocatalyst-containing composition, which is applied onto a substrate and dried or cured. It is preferable to do so.
[0069]
The action mechanism of the photocatalyst represented by titanium oxide as described later is not necessarily clear, but carriers generated by light irradiation react directly with nearby compounds or in the presence of oxygen and water. It is considered that the chemical structure of organic matter is changed by the generated active oxygen species. In the present invention, it is considered that this carrier acts on the binder and other compounds in the wettability changing layer to make it highly hydrophilic.
[0070]
As a photocatalyst used in the present invention, for example, titanium oxide (TiO 2) known as an optical semiconductor₂), Zinc oxide (ZnO), tin oxide (SnO)₂), Strontium titanate (SrTiO)_Three), Tungsten oxide (WO_Three), Bismuth oxide (Bi₂O_Three), And iron oxide (Fe₂O_Three1) or a mixture of two or more selected from these.
[0071]
In the present invention, titanium oxide is particularly preferably used because it has a high band gap energy, is chemically stable, has no toxicity, and is easily available. Titanium oxide includes anatase type and rutile type, and both can be used in the present invention, but anatase type titanium oxide is preferable. Anatase type titanium oxide has an excitation wavelength of 380 nm or less.
[0072]
Examples of such anatase-type titanium oxide include hydrochloric acid peptizer-type anatase-type titania sol (STS-02 manufactured by Ishihara Sangyo Co., Ltd. (average particle size 7 nm), ST-K01 manufactured by Ishihara Sangyo Co., Ltd.), nitric acid solution Examples include glue-type anatase-type titania sol (TA-15 (average particle size: 12 nm) manufactured by Nissan Chemical Co., Ltd.).
[0073]
The smaller the particle size of the photocatalyst, the more effective the photocatalytic reaction takes place. The photocatalyst having an average particle size of 50 nm or less is preferred, and a photocatalyst of 20 nm or less is particularly preferred. Further, the smaller the particle size of the photocatalyst, the smaller the surface roughness of the formed photocatalyst-containing layer, which is preferable. When the particle size of the photocatalyst exceeds 100 nm, the centerline average surface roughness of the photocatalyst-containing layer becomes coarse, and the photocatalyst This is not preferable because the ink repellency of the non-exposed part of the containing layer is lowered and the ink-philicity of the exposed part becomes insufficient.
[0074]
The content of the photocatalyst added to the wettability changing layer can be set in the range of 5 to 60% by weight, preferably 20 to 40% by weight.
[0075]
In such a wettability changing layer, the above-mentioned components are dispersed in a solvent together with other additives as necessary to prepare a coating solution, and this coating solution is applied onto the substrate or the photocatalyst-containing layer. Can be formed. As the solvent to be used, alcohol-based organic solvents such as ethanol and isopropanol are preferable. The application can be performed by a known application method such as spin coating, spray coating, dip coating, roll coating, or bead coating. When an ultraviolet curable component is contained as a binder, the wettability changing layer can be formed by performing a curing treatment by irradiating ultraviolet rays.
[0076]
In the present invention, the thickness of the wettability changing layer is appropriately adjusted depending on whether the wettability changing layer contains a photocatalyst or whether the wettability changing layer is formed on an independently provided photocatalyst containing layer. However, generally, it is preferably 0.001 μm to 1 μm, and particularly preferably in the range of 0.001 μm to 0.2 μm.
[0077]
In the present invention, the wettability changing layer before exposure has a contact angle (θ) of a wet standard reagent formed by mixing formamide and ethylene glycol monoethyl ether, and a cosine value (cos θ) derived from the contact angle. It is necessary to form the wettability changing layer by selecting a material so that the absolute value (| X |) of the average reduction rate falls within the predetermined range.
[0078]
As a suitable method for producing the wettability changing layer having such characteristics, there are the following methods. That is, the wettability changing layer composition is prepared by hydrolytic condensation or cohydrolysis condensation of one or more silicon compounds containing a fluoroalkyl group in the presence of an acid and water. Examples of the hydroalkyl group-containing silicon compound that can be hydrolyzed and condensed include the above general formula Y._nSiX_(4-n)Containing a fluoroalkyl group among the silicon compounds represented by the formula:
Y_pSiX_(4-p)
(Y represents hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule may be the same or different from each other, provided that at least one Y is fluoroalkyl. A hydrocarbon group having a group or a fluoroalkyl group, X represents an alkoxyl group, an acetyl group or a halogen, a plurality of X in one molecule may be the same or different from each other, and p is from 1 to 3 Is an integer.)
The silicon compound represented by can be selected and used.
[0079]
Further, the fluoroalkyl group-containing silicon compound is a silicon compound that can be hydrolytically condensed, if necessary, preferably the above general formula Y_nSiX_(4-n)And may be cohydrolyzed and condensed by mixing with a silicon compound that does not contain a fluoroalkyl group.
[0080]
Fluoroalkyl group-containing silicon compound as described above, preferably the above general formula Y_pSiX_(4-p)And a silicon compound represented by the formula, and if necessary, other silicon compounds are put into a water-soluble solvent such as isopropyl alcohol, and a necessary amount of water and acid are added using an appropriate acid such as about 2 N hydrochloric acid. Is added to obtain an aqueous reaction system having an acidic pH. When this aqueous reaction system preparation solution is subjected to a sol-gel reaction by stirring at an appropriate temperature for an appropriate time, the fluoroalkyl group-containing silicon compound undergoes hydrolysis and condensation, and a composition for a wettability changing layer is obtained. The mixing order of each material such as a fluoroalkyl group-containing silicon compound, other silicon compounds, a solvent, water, and an acid is not particularly limited.
[0081]
The fluoroalkyl group-containing silicon compound is preferably hydrolytically condensed by a sol-gel reaction in the presence of excess water and acid. Specifically, in the reaction system, water is contained relative to the total amount of hydrolyzable and condensable silicon compounds including fluoroalkyl group-containing silicon compounds and silicon compounds not containing fluoroalkyl groups that are mixed as necessary. The molar ratio is usually 200 times or more, preferably 300 times or more, more preferably 400 times or more, and the pH of the reaction system is adjusted to 2 or less.
[0082]
The aqueous reaction system preparation liquid containing a fluoroalkyl group-containing silicon compound and added with water and acid is usually 25 to 100 ° C, preferably 50 to 100 ° C, preferably 10 minutes to 24 hours, preferably The sol-gel reaction is allowed to proceed with stirring for 1-8 hours.
[0083]
The reaction liquid obtained by the sol-gel reaction is a mixture of a fluoroalkyl group-containing silicon compound, another silicon compound, a hydrolyzate thereof, and a dehydration condensate thereof. The reaction solution thus obtained can be used as it is as a composition for a wettability changing layer. Alternatively, from the reaction solution obtained by the sol-gel reaction, water is removed as necessary, dissolved and dispersed in a coating solvent, and other additives are added to prepare a wettability changing layer composition. Also good. The composition for wettability changing layer thus obtained is applied onto a substrate or a photocatalyst-containing layer and dried to give a hydrolytic condensate or co-hydrolysis containing a fluoroalkyl group-containing silicon compound as a condensation unit. A wettability changing layer made of the condensate is formed. By applying the wettability changing layer composition on the substrate or the photocatalyst-containing layer and then heating, the hydrolysis condensation reaction further proceeds during drying of the coating film, so that the silicon compound can be sufficiently condensed. it can. The wettability changing layer thus formed exhibits the specific contact angle (θ) and the absolute value (| X |) of the average reduction rate of cos θ.
[0084]
Further, when it is desired to form a wettability changing layer composition containing a photocatalyst (photocatalyst-containing composition) by the above preparation method, the photocatalyst may be mixed in the reaction system and subjected to hydrolysis condensation. You may mix a photocatalyst with the composition for wettability change layers obtained by hydrolysis condensation. For example, a photocatalyst-containing composition can be obtained by introducing a fine powder of a photocatalyst into a fluoroalkyl group-containing silicon compound as described above, and subjecting this mixture to a sol-gel reaction in the presence of water and an acid for hydrolysis and condensation. Alternatively, a hydrocondensation product obtained by hydrolyzing and condensing a fluoroalkyl group-containing silicon compound by sol-gel reaction in the presence of water and acid and then removing water from the reaction solution Or you may mix a photocatalyst with the liquid which melt | dissolved or disperse | distributed the said condensate again in the solvent. The photocatalyst-containing composition thus obtained is applied onto a substrate and dried or cured to contain a photocatalyst and the absolute value of the specific contact angle (θ) and the average reduction rate of cos θ. A wettability changing layer exhibiting (| X |) can be formed.
[0085]
(Photocatalyst containing layer)
In the present invention, the photocatalyst-containing layer containing the photocatalyst as described above may be provided independently of the wettability changing layer. The photocatalyst-containing layer is not particularly limited as long as the photocatalyst in the photocatalyst-containing layer changes the wettability of the wettability changing layer formed on the photocatalyst-containing layer, and includes a photocatalyst and a binder. It may be a film formed by a photocatalyst alone. In addition, the wettability of the surface may be particularly ink-philic or ink-repellent, but for the convenience of forming a wettability changing layer on this photocatalyst-containing layer, it must be ink-philic. Is preferred.
[0086]
In the case where the photocatalyst-containing layer is formed by the photocatalyst alone, for example, in the case of titanium dioxide, there is a method of forming amorphous titania on the substrate and then changing the phase to crystalline titania by firing. As the amorphous titania used here, for example, hydrolysis, dehydration condensation, tetraethoxytitanium, tetraisopropoxytitanium, tetra-n-propoxytitanium, tetrabutoxytitanium, titanium inorganic salts such as titanium tetrachloride and titanium sulfate, An organic titanium compound such as tetramethoxytitanium can be obtained by hydrolysis and dehydration condensation in the presence of an acid. Next, it can be modified to anatase titania by baking at 400 ° C. to 500 ° C. and modified to rutile type titania by baking at 600 ° C. to 700 ° C.
[0087]
Further, when a binder is used for the photocatalyst-containing layer, it is preferable that the binder main skeleton has a high binding energy so that it is not decomposed by photoexcitation of the photocatalyst. A siloxane compound etc. can be mentioned.
[0088]
When an organopolysiloxane compound is used as a binder in this way, a photocatalyst and an organopolysiloxane compound are dissolved and dispersed in a solvent together with other additives as necessary to prepare a coating solution, and this coating solution is used as a substrate. A photocatalyst containing layer can be formed by applying on top. As the solvent to be used, alcohol-based organic solvents such as ethanol and isopropanol are preferable. The application can be performed by a known application method such as spin coating, spray coating, dip coating, roll coating, or bead coating. When an ultraviolet curable component is contained as a binder, the photocatalyst-containing layer can be formed by irradiating with ultraviolet rays and performing a curing treatment.
[0089]
An amorphous silica precursor can be used as the binder. This amorphous silica precursor has the general formula SiX_FourX is preferably a silicon compound such as halogen, methoxy group, ethoxy group, or acetyl group, silanol as a hydrolyzate thereof, or polysiloxane having an average molecular weight of 3000 or less.
[0090]
Specific examples include tetraethoxysilane, tetraisopropoxysilane, tetra-n-propoxysilane, tetrabutoxysilane, and tetramethoxysilane. In this case, the amorphous silica precursor and the photocatalyst particles are uniformly dispersed in a non-aqueous solvent, hydrolyzed with moisture in the air on the substrate to form silanol, and then at room temperature. A photocatalyst-containing layer can be formed by dehydration condensation polymerization. If dehydration condensation polymerization of silanol is carried out at 100 ° C. or higher, the degree of polymerization of silanol increases and the strength of the film surface can be improved. Moreover, these binders can be used individually or in mixture of 2 or more types.
[0091]
The content of the photocatalyst in the photocatalyst containing layer can be set in the range of 5 to 60% by weight, preferably 20 to 40% by weight. The thickness of the photocatalyst containing layer is preferably in the range of 0.05 to 10 μm.
[0092]
Furthermore, in addition to the above-mentioned photocatalyst and binder, various surfactants, resins, polymers other than resins, oligomers, and the like that can be added to the wettability changing layer can be added to the photocatalyst-containing layer.
[0093]
(Manufacture of pattern formed body)
When the wettability-changing film of the present invention is formed on the surface of a predetermined substrate and light is irradiated in a predetermined pattern, the exposed part becomes highly hydrophilic, and the pattern forming material between the exposed part and the non-exposed part A difference in wettability occurs. Therefore, when a pattern forming material having appropriate wettability with respect to the exposed part or the non-exposed part is supplied to the film surface (substrate surface) by a method such as inkjet, the pattern forming material is applied to the exposed part or the non-exposed part. It can be selectively deposited to form the desired pattern.
[0094]
When the wettability changing film is exposed, light may be irradiated from above the wettability changing film, or when the light transmittance of the substrate is high, light may be irradiated from the substrate side.
[0095]
The photocatalyst used in the present invention has a different wavelength of light for initiating a catalytic reaction depending on its band gap. For example, cadmium sulfide has a visible light of 496 nm and iron oxide has a light of 539 nm, and titanium dioxide has an ultraviolet light of 388 nm. Therefore, pattern exposure is performed using a light beam having an appropriate wavelength in accordance with the photocatalyst to be used. When titanium dioxide is used as a photocatalyst, it is preferable that an ultraviolet component in the range of 400 nm or less, preferably 380 nm or less, is included in the light beam. Examples of light sources including such ultraviolet light include various ultraviolet light sources such as mercury lamps, metal halide lamps, xenon lamps, and excimer lamps.
[0096]
Ink and other coating materials can be used as the pattern forming material that selectively adheres to the surface of the exposed wettability changing film in accordance with the exposure pattern or its negative pattern. When the wettability changing film of the present invention is irradiated with light, the obtained exposed portion becomes an ink-philic region exhibiting good wettability with respect to ink having a surface tension of 20 to 50 mN / m. On the other hand, the non-exposed part of the wettability changing film remains the same as the ink-repellent area as before the light irradiation. Here, the ink-philic region is a region having a small contact angle with the ink, and is a general printing ink, inkjet ink, color filter colored layer ink or black matrix ink, or microlens forming composition. An area having good wettability to an object or the like is meant. The ink repellency region is a region having a large contact angle with ink, and refers to a region having poor wettability with respect to the ink.
[0097]
Accordingly, the wettability-changing film of the present invention is exposed in a predetermined pattern, and an ink having a surface tension of 20 to 50 mN / m is selectively attached to the exposed portion by a method such as ink jetting, whereby high-definition white A pattern without omission is obtained.
[0098]
Particularly preferably, the wettability changing film of the present invention is used to form a pixel portion (colored layer) or a black matrix layer of a color filter used in a color display. That is, a transparent substrate such as quartz glass, pyrex glass, synthetic quartz plate, or transparent resin plate is prepared, and a wettability changing layer containing a photocatalyst is formed on the surface of the transparent substrate, or the photocatalyst-containing layer is wetted. The wettability changing film of the present invention is provided by sequentially forming the property changing layer. Next, the surface of the wettability change film is exposed to light through a photomask, or is exposed to a predetermined pattern by drawing with a laser. Then, a black matrix ink or a colored layer ink is selectively attached to the exposed portion made highly hydrophilic by a method such as inkjet to form a black matrix layer or a colored layer. On top of this, pattern exposure and selective deposition of black matrix ink or colored layer ink are repeated. By such a method, a colored layer and a black matrix layer of each color are sequentially formed on the substrate, and a high-definition color filter without white spots can be efficiently manufactured.
[0099]
【Example】
Example 1
3 g isopropyl alcohol, 0.020 g fluoroalkylsilane (MF-160E from Tochem Products: N- [3- (trimethoxysilyl) propyl] -N ethyl perfluorooctanesulfonamide in 50% by weight isopropyl ether solution), 2 g of alkoxysilane-containing titanium oxide sol inorganic coating agent (Ishihara Sangyo ST-K03) and 4 g of 2N hydrochloric acid were mixed. The resulting mixed liquid contained a total of 0.0005 moles of hydrolyzable and condensable silicon compounds (fluoroalkylsilane and alkoxysilane) and 0.23 moles of water, and had a pH of 1. The mixture was stirred at 100 ° C. for 120 minutes.
[0100]
The obtained reaction liquid was coated on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to obtain a photocatalyst-containing film having a thickness of 0.15 μm.
[0101]
The contact angle of the photocatalyst-containing film surface with respect to the wet standard reagent (31, 40, 47, 56 mN / m) and water was measured with a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science), and the measured value was used. A graph obtained by performing the Zisman plot is shown as a graph a in FIG.
[0102]
Further, the surface of the photocatalyst-containing film is 15 mW / cm by an ultrahigh pressure mercury lamp through a lattice-like photomask.²Table 1 shows the time required for ultraviolet irradiation with an illuminance of (254 nm) until the contact angle with water becomes 0 degrees.
[0103]
[Table 1]

[0104]
(Comparative Example 1)
3 g isopropyl alcohol, 0.030 g fluoroalkylsilane (MF-160E manufactured by Tochem Products: N- [3- (trimethoxysilyl) propyl] -N ethyl perfluorooctanesulfonamide in 50% by weight isopropyl ether solution), 2 g of titanium oxide sol (STS-01 manufactured by Ishihara Sangyo) was mixed and stirred at 100 ° C. for 20 minutes. To this solution, 0.6 g of silica sol Glasca HPC7002 (made by Nippon Synthetic Rubber) and 0.2 g of alkyl alkoxysilane HPC402H (made by Nihon Synthetic Rubber) were mixed. The obtained mixed liquid contained a total of 0.0015 moles of hydrolyzable and condensable silicon compounds (fluoroalkylsilane and alkylalkoxysilane) and 0.095 moles of water, and had a pH of 1.9. The mixture was stirred at 25 ° C. for 20 minutes.
[0105]
The obtained reaction liquid was coated on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to obtain a photocatalyst-containing film having a thickness of 0.15 μm.
[0106]
The contact angle of the photocatalyst-containing film surface with respect to the wetting standard reagent (31, 40, 47, 56 mN / m) was measured with a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science), and A graph obtained by performing the man plot is shown as a graph b in FIG.
[0107]
Further, the surface of the photocatalyst-containing film is 15 mW / cm by an ultrahigh pressure mercury lamp through a lattice-like photomask.²Table 1 shows the time required for ultraviolet irradiation with an illuminance of (254 nm) until the contact angle with water becomes 0 degrees.
[0108]
(Comparative Example 2)
3 g isopropyl alcohol, 0.030 g fluoroalkylsilane (MF-160E manufactured by Tochem Products: N- [3- (trimethoxysilyl) propyl] -N ethyl perfluorooctanesulfonamide in 50% by weight isopropyl ether solution), 2 g of titanium oxide sol (STS-01 manufactured by Ishihara Sangyo Co., Ltd.), 0.6 g of Glasca HPC7002 (manufactured by Nippon Synthetic Rubber) as a silica sol, and 0.2 g of HPC402H (manufactured by Nippon Synthetic Rubber) as an alkylalkoxysilane were mixed. The obtained mixed liquid contained a total of 0.0015 moles of hydrolyzable and condensable silicon compounds (fluoroalkylsilane and alkylalkoxysilane) and 0.095 moles of water, and had a pH of 1.9. The mixture was stirred at 100 ° C. for 20 minutes.
[0109]
The obtained reaction liquid was coated on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to obtain a photocatalyst-containing film having a thickness of 0.15 μm.
[0110]
The contact angle of the photocatalyst-containing film surface with respect to the wetting standard reagent (31, 40, 47, 56 mN / m) was measured with a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science), and A graph obtained by performing the man plot is shown as a graph c in FIG.
[0111]
Further, the surface of the photocatalyst-containing film is 15 mW / cm by an ultrahigh pressure mercury lamp through a lattice-like photomask.²Table 1 shows the time required for ultraviolet irradiation with an illuminance of (254 nm) until the contact angle with water becomes 0 degrees.
[0112]
(Comparative Example 3)
3 g isopropyl alcohol, 0.030 g fluoroalkylsilane (MF-160E manufactured by Tochem Products: N- [3- (trimethoxysilyl) propyl] -N ethyl perfluorooctanesulfonamide in 50% by weight isopropyl ether solution), 2 g of titanium oxide sol (STS-01 manufactured by Ishihara Sangyo), 0.3 g of Glasca HPC7002 (manufactured by Nippon Synthetic Rubber) as a silica sol, and 0.1 g of HPC402H (manufactured by Nippon Synthetic Rubber) as an alkylalkoxysilane were mixed. The obtained liquid mixture contained a total of 0.00075 moles of hydrolytic condensable silicon compounds (fluoroalkylsilane and alkylalkoxysilane) and 0.086 moles of water, and had a pH of 1.8. The mixture was stirred at 100 ° C. for 20 minutes.
[0113]
The obtained reaction liquid was coated on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to obtain a photocatalyst-containing film having a thickness of 0.15 μm.
[0114]
The contact angle of the photocatalyst-containing film surface with respect to the wetting standard reagent (31, 40, 47, 56 mN / m) was measured with a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science), and A graph obtained by performing the man plot is shown as a graph d in FIG.
[0115]
Further, the surface of the photocatalyst-containing film is 15 mW / cm by an ultrahigh pressure mercury lamp through a lattice-like photomask.²Table 1 shows the time required for ultraviolet irradiation with an illuminance of (254 nm) until the contact angle with water becomes 0 degrees.
[0116]
(Comparative Example 4)
3 g isopropyl alcohol, 0.020 g fluoroalkylsilane (MF-160E manufactured by Tochem Products: N- [3- (trimethoxysilyl) propyl] -N ethyl perfluorooctanesulfonamide in 50% by weight isopropyl ether solution), 2 g of alkoxysilane-containing titanium oxide sol inorganic coating agent (Ishihara Sangyo ST-K03) was mixed. The obtained liquid mixture contained a total of 0.0005 moles of hydrolytic condensable silicon compounds (fluoroalkylsilane and alkoxysilane) and 0.056 moles of water, and had a pH of 1.9. The mixture was stirred at 100 ° C. for 20 minutes.
[0117]
The obtained reaction liquid was coated on a non-alkali glass substrate having a thickness of 0.7 mm by a spin coating method to obtain a photocatalyst-containing film having a thickness of 0.15 μm.
[0118]
The contact angle of the photocatalyst-containing film surface with respect to the wet standard reagent (31, 40, 47, 56 mN / m) and water was measured with a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science), and the measured value was used. A graph obtained by performing Zisman plot is shown as a graph e in FIG.
[0119]
Further, the surface of the photocatalyst-containing film is 15 mW / cm by an ultrahigh pressure mercury lamp through a lattice-like photomask.²Table 1 shows the time required for ultraviolet irradiation with an illuminance of (254 nm) until the contact angle with water becomes 0 degrees.
[0120]
【The invention's effect】
As described above, according to the present invention, the wettability changing film that covers the surface of a predetermined substrate, exhibits high water repellency before light irradiation, and quickly becomes highly hydrophilic by light irradiation, and so on. A photocatalyst-containing composition suitable for forming a wettability-changing film is provided. When the surface of this wettability changing film is exposed in a predetermined pattern, the difference in wettability with respect to the pattern forming material can be sufficiently large between the exposed part and the non-exposed part. The difference in wettability can be increased. Therefore, by utilizing the fact that there is a large difference in wettability between the exposed part and the non-exposed part, the pattern forming material can be selectively attached to the exposed part or the non-exposed part. Thus, a pattern without white spots can be formed. Moreover, since the wettability changing film of the present invention has high sensitivity, the exposure process time can be extremely shortened, and the productivity is high.
[0121]
Furthermore, by using the wettability changing film and the photocatalyst-containing composition of the present invention, it is possible to efficiently produce a color filter for color liquid crystal displays that does not have white spots.
[0122]
Furthermore, the composition for wettability changing layer for producing the wettability changing layer having the above-described characteristics is obtained by using one or more silicon compounds containing a fluoroalkyl group in the presence of acid and water. Can be prepared by hydrolytic condensation or cohydrolytic condensation.
[Brief description of the drawings]
FIG. 1 is a zisman plot for explaining characteristics of a wettability changing film of the present invention. In the graph, a represents the wettability changing film of the present invention, and b to e represent wettability changing films not belonging to the present invention.

Claims (15)

A photocatalyst-containing composition for forming a wettability changing film that becomes hydrophilic by a photocatalytic reaction,
The photocatalyst-containing composition contains at least a binder and a photocatalyst,
A contact angle (θ) is obtained by bringing a droplet of a wet standard reagent formed by mixing formamide and ethylene glycol monoethyl ether into contact with the surface of a film that has been formed using the photocatalyst-containing composition and has not yet been hydrophilized. When measuring and creating a Zisman plot graph,
The contact angle (θ) measured or determined by the Zisman plot of the wet standard reagent shows 30 degrees or more in all or part of the range of the surface tension of 20 to 50 mN / m, and
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) is 0 in the range where the surface tension is 20 to 50 mN / m. 0.02 or less, A photocatalyst-containing composition.   The critical surface tension of a film not yet hydrophilized formed using the photocatalyst-containing composition is 40 mN / m or less when the wet standard reagent is used. A photocatalyst-containing composition.   The photocatalyst-containing composition according to claim 1 or 2, wherein the coating film formed using the photocatalyst-containing composition and not yet hydrophilized has a contact angle (θ) with respect to water of 80 degrees or less. object. The photocatalyst is titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), strontium titanate (SrTiO ₃ ), tungsten oxide (WO ₃ ), bismuth oxide (Bi ₂ O ₃ ), and The photocatalyst-containing composition according to any one of claims 1 to 3, wherein the photocatalyst-containing composition is one or more substances selected from iron oxide (Fe ₂ O ₃ ).     2. The hydrolyzable-condensable silicon compound or a reaction product obtained by hydrolyzing and / or condensing at least a part of the hydrolyzable-condensable silicon compound as the binder. The photocatalyst containing composition in any one of thru | or 4.   6. The photocatalyst-containing composition according to claim 5, wherein at least a part of the hydrolyzable and condensable silicon compound has a fluoroalkyl group. The silicon compound which can be hydrolyzed and condensed is YnSiX _(4-n) (Y is hydrogen or a hydrocarbon group which may have a substituent. A plurality of Y in one molecule are the same as each other. X represents an alkoxyl group, an acetyl group, or a halogen, a plurality of X in one molecule may be the same or different from each other, and n is an integer from 0 to 3. The photocatalyst-containing composition according to claim 6, wherein at least a part thereof has a fluoroalkyl group. A wettability changing film that coats a predetermined substrate surface and becomes hydrophilic by photocatalytic reaction,
The wettability changing film includes a wettability changing layer that is hydrophilized by a photocatalytic reaction, and a photocatalytic system that causes the photocatalytic reaction of the wettability changing layer.
The surface of the wettability change layer that has not yet been hydrophilized is brought into contact with a wet standard reagent droplet formed by mixing formamide and ethylene glycol monoethyl ether, and the contact angle (θ) is measured. When creating a graph,
The contact angle (θ) measured or determined by the Zisman plot of the wet standard reagent shows 30 degrees or more in all or part of the range of the surface tension of 20 to 50 mN / m, and
X = (cos θ (A) −cos θ (B)) ÷ (A−B)
(In the formula, X is the average reduction rate of cos θ, A is the surface tension (mN / m) at the start point of the range for which the average reduction rate is obtained, B is the surface tension (mN / m) at the end point of the range for which the average reduction rate is obtained, (θ (A) is the contact angle at the surface tension A at the start point, and θ (B) is the contact angle at the surface tension B at the end point.)
The absolute value (| X |) of the average reduction rate (X) of the cosine value (cos θ) derived from the contact angle (θ) is 0 in the range where the surface tension is 20 to 50 mN / m. 0.02 or less, the wettability changing film.   The wettability changing film according to claim 8, wherein the wettability changing film includes the wettability changing layer containing a photocatalyst.   The said wettability change film | membrane is provided with the photocatalyst containing layer containing a photocatalyst, and the said wettability change layer provided on the said photocatalyst containing layer, The wetting of Claim 8 characterized by the above-mentioned. Sex change film.   The wettability according to any one of claims 8 to 10, wherein a critical surface tension of the wettability changing layer that has not been hydrophilized is 40 mN / m or less when the wet standard reagent is used. Change coating.   The wettability changing film according to any one of claims 8 to 11, wherein the surface of the wettability changing layer that has not yet been made hydrophilic has a contact angle (θ) with respect to water of 80 degrees or less.   The wettability changing film according to any one of claims 8 to 12, wherein the wettability changing layer contains an organopolysiloxane compound as a binder.   The wettability changing film according to claim 13, wherein the organopolysiloxane compound has a fluoroalkyl group. The organopolysiloxane compound having a fluoroalkyl group is represented by YnSiX _(4-n) (Y represents hydrogen or a hydrocarbon group which may have a substituent. X may be an alkoxyl group, an acetyl group or a halogen, a plurality of X in one molecule may be the same or different, and n is an integer from 0 to 3. A hydrolytic condensate or a cohydrolytic condensate containing a silicon compound having one or more of the silicon compounds represented by formula (2) as a condensation unit and having a fluoroalkyl group as the condensation unit. The wettability changing film according to claim 14, wherein the wettability changing film is provided.

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