JP2004083832A - Photocatalytic coating material, method for forming film by using the same, and coated material having photocatalytic function by applying the same material - Google Patents
Photocatalytic coating material, method for forming film by using the same, and coated material having photocatalytic function by applying the same material Download PDFInfo
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- XPPKVPWEQAFLFU-UHFFFAOYSA-J diphosphate(4-) Chemical group [O-]P([O-])(=O)OP([O-])([O-])=O XPPKVPWEQAFLFU-UHFFFAOYSA-J 0.000 description 2
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- Catalysts (AREA)
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Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、可視光領域での応答性に優れた光触媒塗料及びその成膜方法並びに該塗料を塗布して得られた光触媒機能を有するコーティング材に関するものである。
【０００２】
【従来の技術】
従来、光触媒として光触媒活性が高いアナターゼ型結晶構造を有する酸化チタンが使用されている。しかしながら、このアナターゼ型酸化チタンは約３．２ｅＶ（約３８０ｎｍ）のバンドギャップを有するため、光触媒活性に利用できる光の波長は約３８０ｎｍ以下の紫外線にしか利用できず、利用範囲が限られているという欠点があった。
従って、利用できる光の波長を可視光領域にまで広げることができれば、紫外線が極めて少ない環境下でも光触媒活性が発現できることになり、光触媒の応用範囲を拡大することが可能となる。
このような可視光領域の波長を有する光に感応する光触媒として、酸化チタン、酸化亜鉛、チタン酸ストロンチウム、酸化タングステン及び炭化珪素からなる群より選択される少なくとも一種類に、バナジウム、クロム、マンガン、鉄、コバルト、ニッケル及び銅からなる群より選択される少なくとも一種類のドーパントがドーピングされていることを特徴とする光触媒が開示されている（特開平９−１９２４９６）。また可視光領域の光を利用する触媒として、クロム等をイオン注入した光触媒、酸素イオンを窒素で置換した光触媒等も研究されている。
【０００３】
【発明が解決しようとする課題】
しかし、特開平９−１９２４９６号公報等に示された光触媒では、可視光下での光触媒活性は未だ実用上十分とはいえなかった。
本発明の目的は、可視光領域での応答性に優れ、かつ透明性が良好な光触媒塗料及びその成膜方法並びに該塗料を塗布して得られた光触媒機能を有するコーティング材を提供することにある。
本発明の別の目的は、高い硬度を有し、透明性の低下を抑制し得る光触媒塗料及びその成膜方法並びに該塗料を塗布して得られた光触媒機能を有するコーティング材を提供することにある。
【０００４】
【課題を解決するための手段】
請求項１に係る発明は、酸化チタン微粒子とシリカ微粒子をそれぞれ含む光触媒塗料の改良であり、その特徴ある構成は、酸化チタン微粒子がルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５で含み、酸化チタン微粒子の平均粒径が０．０１〜０．０５μｍであり、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）が７０／３０〜９５／５であるところにある。
この請求項１に記載された光触媒塗料を基材に塗布することにより形成されたコーティング材は、可視光領域での応答性に優れ、かつ透明性が良好である。また上記コーティング材の硬度が高いので、このコーティング材は傷がつき難く、透明性の低下を抑制できる。
【０００５】
請求項２に係る発明は、請求項１記載の光触媒塗料を基材上に塗布し、塗布した基材を乾燥することを特徴とする成膜方法である。
請求項３に係る発明は、請求項１記載の光触媒塗料を基材表面に塗布して形成されたことを特徴とする光触媒機能を有するコーティング材である。
請求項４に係る発明は、請求項３に係る発明であって、基材表面に無機質の下地層と、下地層の上に光触媒塗料から形成された光触媒膜とを有するコーティング材である。
請求項５に係る発明は、請求項３又は４に係る発明であって、基材がガラス、プラスチック、金属、木材、タイルを含むセラミック、セメント、コンクリート、石、繊維、紙及び皮革からなる群より選ばれた材質であるコーティング材である。
請求項６に係る発明は、請求項４に係る発明であって、無機質の下地層がシリカ又はアルミナからなるコーティング材である。
【０００６】
請求項７に係る発明は、請求項３ないし６いずれか記載のコーティング材により表面被覆を行った石材加工品である。
請求項８に係る発明は、請求項３ないし６いずれか記載のコーティング材により表面被覆を行った壁材である。
請求項９に係る発明は、請求項３ないし６いずれか記載のコーティング材により表面被覆を行った硝子である。
【０００７】
【発明の実施の形態】
次に本発明の実施の形態を説明する。
本発明の光触媒塗料は、酸化チタン微粒子とシリカ微粒子をそれぞれ含む。
その特徴ある構成は、酸化チタン微粒子がルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５で含み、酸化チタン微粒子の平均粒径が０．０１〜０．０５μｍであり、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）が７０／３０〜９５／５であるところにある。
【０００８】
酸化チタン微粒子はルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５の範囲内となるように規定される。重量比を上記範囲内となるように配合することで、ルチル型酸化チタン微粒子で可視光に応答させるとともに、アナターゼ型酸化チタン微粒子で太陽光や蛍光灯等に含まれる微弱な紫外線に応答させる。この紫外線応答作用も利用することで複合的に触媒活性を向上させるため、可視光で応答し、実用上十分な触媒活性を発現することができる。好ましい重量比は８０／２０〜９０／１０である。重量比が７０／３０未満、即ちルチル型酸化チタンの割合が小さいと、可視光下において得られる光触媒効果が実用上十分とはいえず、重量比が９５／５を越える、即ちルチル型酸化チタンの割合が大き過ぎても光触媒活性が向上しない。
またこの酸化チタン微粒子の平均粒径は０．０１〜０．０５μｍに規定される。好ましい平均粒径は０．０３〜０．０４μｍである。平均粒径が０．０１μｍ未満のものは入手が困難であり、０．０５μｍを越えると光触媒塗料から形成されるコーティング材の透明性が著しく低下する。
【０００９】
上記範囲内の平均粒径を有する酸化チタン微粒子は気相法と液相法のいずれでも製造可能であるけれども、本発明では気相法で製造されたものが用いられる。気相法による酸化チタン微粒子の製造は一般に四塩化チタンガスの熱酸化分解により行われるが、この方法に制限されず、気相法であれば他の方法で製造してもよい。四塩化チタンガスから製造された酸化チタン微粒子としては、例えばＰ−２５（日本アエロジル社の商品名）が市販されている。気相法により製造された酸化チタン微粒子はその結晶構造がアナターゼ型リッチであるため、このアナターゼ型リッチ酸化チタン微粒子を８００〜９５０℃で焼成し、ルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５の範囲内となるようにルチル型結晶構造へと部分的に転位させることにより本発明の酸化チタン微粒子が得られる。また、それぞれの結晶構造の割合が規定されているルチル型リッチ酸化チタン微粒子とアナターゼ型リッチ酸化チタン微粒子を上記範囲内となるように混合して本発明の酸化チタン微粒子を調製することも考えられる。しかし、１００％ルチル型の酸化チタンはアナターゼ型酸化チタンを焼成することで得られるが、焼結するため解砕しても凝集体を本発明の平均粒径の範囲内に分散させることが困難なため、実用的とはいえない。
【００１０】
図１に示すように、ルチル型結晶構造を有する酸化チタン微粒子はアナターゼ型酸化チタン微粒子に比べ、そのバンドギャップが小さく、紫外領域に近い可視光領域の４１５ｎｍ以下で光励起する。そのため紫外線領域における光触媒効果はアナターゼ型に比べて低い。しかし、可視光領域における効果はアナターゼ型よりも高い傾向がみられる。またその結晶構造が安定していることから、過酷な環境下に曝された場合でも経年劣化が少なく、安定した性能が長期間継続して得られるという利点がある。一方、アナターゼ型酸化チタン微粒子は、紫外線領域の３８０ｎｍ以下で光励起し、この紫外線領域における光触媒効果は高い。しかしながら可視光領域における光触媒効果はルチル型よりも低い傾向がみられる。そのため、ルチル型とアナターゼ型を本発明の規定する範囲内に混合することで、ルチル型とアナターゼ型がそれぞれが有する欠点を補うことができる。
【００１１】
酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）は７０／３０〜９５／５の範囲内に規定される。好ましい重量比は８０／２０〜９０／１０である。重量比が７０／３０未満、即ち酸化チタン微粒子の割合が小さいと、可視光下における光触媒効果が実用上十分ではなく、重量比が９５／５を越える、即ち酸化チタン微粒子の割合が大きいと、得られるコーティング材の硬度が低下する不具合を生じる。シリカ微粒子はエチルシリケート、アルコール、酸及び水の混合物を加熱撹拌して調製されることが好ましい。
本発明の光触媒塗料に含まれる酸化チタン微粒子の含有量は０．５〜２０重量％の範囲内とすることが好ましい。酸化チタン微粒子の含有量が０．５重量％未満では十分な光触媒効果が得られず、２０重量％を越えると酸化チタンの分散性が低下し、形成する光触媒薄膜のヘイズが悪化するおそれがあるためである。塗料中の酸化チタン微粒子含有量は１．０〜１０．０重量％の範囲内が更に好ましい。
【００１２】
本発明の光触媒塗料にはβ−ジケトン、チタネート系又はアルミニウム系カップリング剤及び有機溶媒を更に含むことが好ましい。これは有機溶媒にβ−ジケトンとカップリング剤を混合することにより、酸化チタン微粒子の分散性が改善され、塗料の保存安定性が良好になり、得られたコーティング材の透明性が高められるためである。
β−ジケトンとしては、２，４−ペンタンジオン、３−メチル−２，４−ペンタンジオン、３−イソプロピル−２，４−ペンタンジオン、２，２−ジメチル−３，５−ヘキサンジオン等が挙げられる。β−ジケトンは酸化チタン微粒子に対して０．５〜１０重量％の割合で含有させると分散性が向上するため、より光触媒効果が向上する。１．０〜５．０重量％の割合で含有させることが好ましい。β−ジケトンの含有量が０．５重量％未満では、十分な分散性が得られず、１０．０重量％を越えても更なる分散性の向上にはならないおそれがある。
【００１３】
カップリング剤は低ヘイズ化剤として作用する。カップリング剤を添加することにより、膜構造に二次凝集群を形成せず、均一な最密充填化と表面の平滑精度がより一層高められるためにヘイズが低下（透明性が向上する）すると推測される。
アルミニウム系カップリング剤としては、アセトアルコキシ基を有するアルミネート系カップリング剤が挙げられる。アセトアルコキシ基を有するアルミネート系カップリング剤としては、次の式（１）で示される化合物がある。
【００１４】
【化１】
チタネート系カップリング剤としては、ジアルキルパイロホスフェート基もしくはジアルキルホスファイト基を有するチタネート系カップリング剤が挙げられる。ジアルキルパイロホスフェート基を有するチタネート系カップリング剤としては、次の式（２）〜式（４）で示される化合物が挙げられる。
【００１６】
【化２】
ジアルキルホスファイト基を有するチタネート系カップリング剤としては次の式（５）及び式（６）で示される化合物が挙げられる。
【００１８】
【化５】
カップリング剤はこれらの１種もしくは２種以上を使用することができる。チタネート系又はアルミニウム系カップリング剤は酸化チタン微粒子に対して０．１〜５重量％の割合で含有させるのが好適である。それはカップリング剤の含有量が０．１重量％未満では分散性及びヘイズ低下の効果が得られず、５．０重量％を越えても更なるヘイズ低下や分散性の向上にはならないためである。０．５〜２．０重量％の割合で含有させることが望ましい。
【００２０】
有機溶媒は沸点１７０℃以下の単一のアルコール又は複数種類のアルコールの混合溶媒が好適である。混合アルコールとしては、メチルアルコールとエチルアルコールからなる混合液が好ましい。光触媒塗料に含まれる溶媒の量は、塗布に適した粘度が得られればよく、特に制限されない。
本発明の光触媒塗料を得るには、先ず、有機溶媒にβ−ジケトンと、チタネート系又はアルミネート系のいずれか一方又は双方のカップリング剤とを混合して混合液を調製する。次にこの混合液に酸化チタン微粒子を混合・分散して酸化チタン微粒子の分散液を調製する。更にこの分散液にシリカ微粒子を混合することにより得られる。
【００２１】
本発明の成膜方法は、前述した本発明の光触媒塗料を基材上に塗布し、塗布した基材を乾燥することを特徴とする。塗布方法としては従来より用いられているスピンコート法、ドクターブレード法、ディッピング法、刷毛塗り、スプレー法、ロールコーター法等により施すことができるが、特に塗布方法は限定されない。
光触媒塗料を例えば上述した塗布方法により所定の基材表面に塗布し、乾燥することにより、その表面に光触媒機能を有するコーティング材が得られる。また基材表面に無機質の下地層を形成し、この下地層の上に光触媒塗料を塗布、乾燥して光触媒膜を形成して光触媒機能を有するコーティング材を得ることもできる。
【００２２】
本発明の基材に使用される材質には、ガラス、プラスチック、金属、木材、タイルを含むセラミック、セメント、コンクリート、石、繊維、紙及び皮革からなる群より選ばれる。ガラスとしては、蛍光灯、窓等の室内環境浄化（汚染物質分解）ガラス、水槽、生け簀等の水質浄化ガラス、車の防曇ガラス、ＣＲＴ、ＬＣＤ画面、窓、鏡、眼鏡等の防汚ガラス、カメラ、光学機器の防汚、防黴レンズ等がある。プラスチックとしては、ＡＶ機器、コンピューター、マウス、キーボード、リモコン、フロッピーディスク、等の機器及びその周辺製品、車の内装品、家具、キッチン、風呂、洗面所等で使用する家庭用品等の使用する防汚、抗菌、防黴プラスチック等がある。金属としては、物干し台、物干し竿、キッチン、実験室等の作業台や洗い場、換気扇等に使用する防汚、抗菌、防黴ステンレス、防汚、抗菌処理ドアノブ等がある。木材の用途としては、防汚家具、公園の抗菌遊技施設等がある。タイルを含むセラミック、セメント、コンクリート、石等の建材としては、防汚処理した外壁材、屋根、床材等、室内環境浄化（汚染物質分解）性を持つ内壁材、防汚、抗菌、防黴処理した各種内装品等がある。紙としては、抗菌処理文房具等に使用できる。フィルム等の繊維としては、食品包装用透明抗菌フィルム、野菜保存用透明エチレンガス分解フィルム、環境、水質浄化用フィルム等がある。このように各種基材は、防汚、環境浄化、抗菌、防黴の効果を有するので、太陽光や蛍光灯等から発せられる可視光及び紫外線の照射が可能な条件であれば、例示した以外でも多くの用途に使用することができる。無機質の下地層としてはシリカ、アルミナ等が挙げられる。本発明のコーティング材により表面被覆を行った石材加工品、壁材又は硝子は透明性及び硬度に優れるとともに高い分解性能を示す。
【００２３】
【実施例】
次に本発明の実施例を比較例とともに詳しく説明する。
＜実施例１＞
平均粒径０．０１μｍ、ルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を７０／３０とした酸化チタン微粒子を用意した。また有機溶媒としてエタノールを、β−ジケトンとして２，４−ペンタンジオンを、カップリング剤として上記化学式（２）に示されるチタネート系カップリング剤をそれぞれ用意した。
有機溶媒、β−ジケトン、カップリング剤及び酸化チタンをそれぞれ混合し、ジリコニアビーズ１００ｇにより１６時間ペイントシェーカーにて分散させた。β−ジケトンの添加量は、酸化チタンに対して２．０重量％とし、カップリング剤の添加量は、酸化チタンに対して０．５重量％とした。この分散液に酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）が７０／３０となるようにシリカ微粒子含有溶液を混合し、光触媒塗料を調製した。調製した塗料中のＴｉＯ２含有量は０．５重量％であった。
【００２４】
＜実施例２＞
酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とした以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例３＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とした以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例４＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例５＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例６＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
【００２５】
＜実施例７＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例８＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例９＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１０＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１１＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
【００２６】
＜実施例１２＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１３＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１４＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１５＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１６＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
【００２７】
＜実施例１７＞
酸化チタン微粒子の平均粒径を０．０３μｍとした以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例１８＞
酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とした以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例１９＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とした以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２０＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２１＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２２＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
【００２８】
＜実施例２３＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２４＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２５＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２６＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２７＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
【００２９】
＜実施例２８＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例２９＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、溶媒にメタノールを用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例３０＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒にメタノールを用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例３１＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒にメタノールを用いた以外は実施例１７と同様にして光触媒塗料を調製した。
＜実施例３２＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例１７と同様にして光触媒塗料を調製した。
【００３０】
＜実施例３３＞
酸化チタン微粒子の平均粒径を０．０４μｍとした以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例３４＞
酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とした以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例３５＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とした以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例３６＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例３７＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例３８＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
【００３１】
＜実施例３９＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４０＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４１＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４２＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４３＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
【００３２】
＜実施例４４＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４５＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、溶媒にメタノールを用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４６＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒にメタノールを用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４７＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒にメタノールを用いた以外は実施例３３と同様にして光触媒塗料を調製した。
＜実施例４８＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例３３と同様にして光触媒塗料を調製した。
【００３３】
＜実施例４９＞
酸化チタン微粒子の平均粒径を０．０５μｍとした以外は実施例１と同様にして光触媒塗料を調製した。
＜実施例５０＞
酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とした以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５１＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とした以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５２＞
塗料中のＴｉＯ２含有量を１重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５３＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５４＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に３０重量％エタノールと７０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
【００３４】
＜実施例５５＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５６＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を８０／２０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５７＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、溶媒に５０重量％エタノールと５０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５８＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例５９＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
【００３５】
＜実施例６０＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９０／１０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒に７０重量％エタノールと３０重量％メタノールとの混合溶媒を用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例６１＞
塗料中のＴｉＯ２含有量を１５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、溶媒にメタノールを用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例６２＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を８０／２０とし、溶媒にメタノールを用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例６３＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９０／１０とし、溶媒にメタノールを用いた以外は実施例４９と同様にして光触媒塗料を調製した。
＜実施例６４＞
塗料中のＴｉＯ２含有量を２０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例４９と同様にして光触媒塗料を調製した。
【００３６】
＜比較例１＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を６５／３５とした以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例２＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を６５／３５とした以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例３＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を１００／０、即ちシリカ微粒子を塗料中に混入させない以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例４＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を１００／０、即ちシリカ微粒子を塗料中に混入させない以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例５＞
塗料中のＴｉＯ２含有量を５重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を６５／３５とした以外は実施例１と同様にして光触媒塗料を調製した。
【００３７】
＜比較例６＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を６５／３５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例７＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を１００／０とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例８＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を１００／０とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例９＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子の平均粒径を０．０６μｍとし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
＜比較例１０＞
塗料中のＴｉＯ２含有量を１０重量％とし、酸化チタン微粒子の平均粒径を０．０６μｍとし、酸化チタン微粒子のルチル型結晶構造とアナターゼ型結晶構造との重量比（ルチル型／アナターゼ型）を９５／５とし、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）を９５／５とし、溶媒にメタノールを用いた以外は実施例１と同様にして光触媒塗料を調製した。
【００３８】
＜比較試験及び評価＞
実施例１〜６４及び比較例１〜１０でそれぞれ調製した光触媒塗料をスピンコーターで１０ｃｍ×１０ｃｍのガラス基板に塗布し、１５０℃で１時間乾燥させることにより、ガラス基板表面に光触媒薄膜が形成されたコーティング材を得た。
このようにして得られたコーティング材の光触媒薄膜について、光触媒薄膜のヘイズ、鉛筆硬度及び光触媒活性をそれぞれ測定した。なお、ヘイズ測定にはスガ試験機社製ヘイズコンピューターＨＧＭ−３Ｄを用いた。また光触媒活性は、以下に示す手順により求めた除去率を光触媒活性の指標とした。先ず、１Ｌのガラス（パイレックス）製容器に薄膜形成面を上に向けてガラス基板を入れて、容器を密閉した。次いで容器内に１０ｐｐｍ（初期濃度）のアセトアルデヒドを導入した。次に、この容器の上２０ｃｍの距離に蛍光灯（商品名：ナショナルツイン７、２７Ｗ型）を設置し、この容器に向けて蛍光灯で２時間照射した。この蛍光灯から発せられる光の波長は４１０〜８１０ｎｍであった。照射後の容器内部のアセトアルデヒド濃度をガス検知管（ガステック社製）で測定し、下記に示す式に基づいて除去率を求めた。
除去率［％］＝［（初期濃度−光照射後の濃度）÷初期濃度］×１００
実施例１〜６４及び比較例１〜１０の光触媒塗料から形成したコーティング材の光触媒薄膜についてそれぞれ測定した結果を表１にそれぞれ示す。
【００３９】
【表１】
【表２】
【表３】
表１〜表３より明らかなように、本発明の範囲から外れた比較例１〜１０の光触媒塗料から得た薄膜は鉛筆硬度が低い、ヘイズが大きい、アセトアルデヒド除去率が小さい等、実用上十分とはいえない結果が得られた。これに対して本発明の範囲内に規定した実施例１〜６４の光触媒塗料から得た薄膜は十分な硬度で、小さいヘイズ値を有し、アセトアルデヒド除去率も実用上十分な効果が得られていることが判る。
【００４３】
【発明の効果】
以上述べたように、本発明の光触媒塗料は、酸化チタン微粒子とシリカ微粒子をそれぞれ含む塗料の改良であり、その特徴ある構成は、酸化チタン微粒子がルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５で含み、酸化チタン微粒子の平均粒径が０．０１〜０．０５μｍであり、酸化チタン微粒子とシリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）が７０／３０〜９５／５であるところにある。このように調製された光触媒塗料を基材に塗布し、塗布した基材を乾燥することにより形成されたコーティング材は、可視光領域での応答性に優れ、かつ透明性が良好となる。また上記コーティング材の硬度が高いので、このコーティング材は傷がつき難く、透明性の低下を抑制できる。
【図面の簡単な説明】
【図１】各結晶構造における光触媒効果と波長との関係を示す図。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photocatalytic paint having excellent responsiveness in the visible light region, a method for forming the same, and a coating material having a photocatalytic function obtained by applying the paint.
[0002]
[Prior art]
Conventionally, titanium oxide having an anatase crystal structure having high photocatalytic activity has been used as a photocatalyst. However, since this anatase type titanium oxide has a band gap of about 3.2 eV (about 380 nm), the wavelength of light that can be used for photocatalytic activity can be used only for ultraviolet light of about 380 nm or less, and the range of use is limited. There was a disadvantage.
Therefore, if the wavelength of light that can be used can be extended to the visible light region, photocatalytic activity can be exhibited even in an environment where the amount of ultraviolet light is extremely small, and the application range of the photocatalyst can be expanded.
As a photocatalyst sensitive to light having a wavelength in the visible light region, titanium oxide, zinc oxide, strontium titanate, tungsten oxide and at least one selected from the group consisting of silicon carbide, vanadium, chromium, manganese, A photocatalyst characterized by being doped with at least one kind of dopant selected from the group consisting of iron, cobalt, nickel and copper has been disclosed (JP-A-9-192496). Further, as a catalyst utilizing light in the visible light region, a photocatalyst in which chromium or the like is ion-implanted, a photocatalyst in which oxygen ions are replaced with nitrogen, and the like have been studied.
[0003]
[Problems to be solved by the invention]
However, the photocatalysts disclosed in JP-A-9-192496 and the like have not been sufficiently practical for photocatalytic activity under visible light.
An object of the present invention is to provide a photocatalytic paint having excellent responsiveness in a visible light region and excellent transparency, a method for forming the same, and a coating material having a photocatalytic function obtained by applying the paint. is there.
Another object of the present invention is to provide a photocatalytic paint having high hardness and capable of suppressing a decrease in transparency, a method of forming the same, and a coating material having a photocatalytic function obtained by applying the paint. is there.
[0004]
[Means for Solving the Problems]
The invention according to claim 1 is an improvement of a photocatalytic paint containing titanium oxide fine particles and silica fine particles, respectively. The characteristic feature of the invention is that the titanium oxide fine particles have a rutile type crystal structure and an anatase type crystal structure in a weight ratio (rutile). Type / anatase type) in an amount of 70/30 to 95/5, the average particle size of the titanium oxide fine particles is 0.01 to 0.05 μm, and the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica (Fine particles) is 70/30 to 95/5.
The coating material formed by applying the photocatalytic paint according to claim 1 to a substrate has excellent responsiveness in the visible light region and good transparency. Further, since the hardness of the coating material is high, the coating material is hardly damaged, and a decrease in transparency can be suppressed.
[0005]
According to a second aspect of the present invention, there is provided a film forming method comprising applying the photocatalyst paint according to the first aspect on a substrate and drying the applied substrate.
According to a third aspect of the present invention, there is provided a coating material having a photocatalytic function, which is formed by applying the photocatalytic paint according to the first aspect to a substrate surface.
The invention according to claim 4 is the invention according to claim 3, which is a coating material having an inorganic base layer on the surface of the base material and a photocatalytic film formed of a photocatalytic paint on the base layer.
The invention according to claim 5 is the invention according to claim 3 or 4, wherein the substrate is made of glass, plastic, metal, wood, ceramic including tile, cement, concrete, stone, fiber, paper, and leather. It is a coating material that is a more selected material.
The invention according to claim 6 is the invention according to claim 4, wherein the inorganic underlayer is a coating material made of silica or alumina.
[0006]
According to a seventh aspect of the present invention, there is provided a processed stone product having a surface coated with the coating material according to any one of the third to sixth aspects.
The invention according to claim 8 is a wall material which has been surface-coated with the coating material according to any one of claims 3 to 6.
A ninth aspect of the present invention is a glass surface-coated with the coating material according to any one of the third to sixth aspects.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described.
The photocatalytic paint of the present invention contains titanium oxide fine particles and silica fine particles, respectively.
The characteristic configuration is that the titanium oxide fine particles contain a rutile type crystal structure and an anatase type crystal structure in a weight ratio (rutile type / anatase type) of 70/30 to 95/5, and the average particle size of the titanium oxide fine particles is 0.01 to 0.05 μm, and the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) is 70/30 to 95/5.
[0008]
The titanium oxide fine particles are defined so that the weight ratio (rutile type / anatase type) of the rutile type crystal structure to the anatase type crystal structure is in the range of 70/30 to 95/5. By blending the weight ratio within the above range, the rutile-type titanium oxide fine particles respond to visible light, and the anatase-type titanium oxide fine particles respond to weak ultraviolet light contained in sunlight, fluorescent lamps and the like. Utilizing this ultraviolet response, the catalytic activity is improved in a complex manner, so that it is possible to respond to visible light and exhibit a practically sufficient catalytic activity. The preferred weight ratio is between 80/20 and 90/10. If the weight ratio is less than 70/30, that is, if the proportion of rutile type titanium oxide is small, the photocatalytic effect obtained under visible light cannot be said to be practically sufficient, and the weight ratio exceeds 95/5, ie, rutile type titanium oxide. Is too large, the photocatalytic activity is not improved.
The average particle size of the titanium oxide fine particles is defined to be 0.01 to 0.05 μm. The preferred average particle size is 0.03 to 0.04 µm. If the average particle size is less than 0.01 μm, it is difficult to obtain. If the average particle size exceeds 0.05 μm, the transparency of the coating material formed from the photocatalytic coating material is significantly reduced.
[0009]
Although titanium oxide fine particles having an average particle diameter within the above range can be produced by either a gas phase method or a liquid phase method, those produced by a gas phase method are used in the present invention. The production of titanium oxide fine particles by a gas phase method is generally performed by thermal oxidative decomposition of titanium tetrachloride gas, but is not limited to this method, and may be produced by another method as long as it is a gas phase method. As titanium oxide fine particles produced from titanium tetrachloride gas, for example, P-25 (trade name of Nippon Aerosil Co., Ltd.) is commercially available. Since the titanium oxide fine particles produced by the gas phase method have an anatase-rich crystal structure, the anatase-rich titanium oxide fine particles are calcined at 800 to 950 ° C. to convert the rutile-type crystal structure and the anatase-type crystal structure into The titanium oxide fine particles of the present invention can be obtained by partially displacing a rutile crystal structure so that the weight ratio (rutile type / anatase type) is in the range of 70/30 to 95/5. It is also conceivable to prepare the titanium oxide fine particles of the present invention by mixing the rutile-type rich titanium oxide fine particles and the anatase-type rich titanium oxide fine particles in which the proportions of the respective crystal structures are defined so as to be within the above range. . However, although 100% rutile-type titanium oxide is obtained by calcining anatase-type titanium oxide, it is difficult to disperse the aggregates within the range of the average particle size of the present invention even if crushed due to sintering. Therefore, it is not practical.
[0010]
As shown in FIG. 1, titanium oxide fine particles having a rutile-type crystal structure have a smaller band gap than anatase-type titanium oxide fine particles, and are photoexcited at 415 nm or less in a visible light region close to an ultraviolet region. Therefore, the photocatalytic effect in the ultraviolet region is lower than that of the anatase type. However, the effect in the visible light region tends to be higher than that of the anatase type. Further, since the crystal structure is stable, there is an advantage that even when exposed to a severe environment, there is little aging and stable performance can be continuously obtained for a long time. On the other hand, the anatase type titanium oxide fine particles are photoexcited at 380 nm or less in the ultraviolet region, and have a high photocatalytic effect in this ultraviolet region. However, the photocatalytic effect in the visible light region tends to be lower than that of the rutile type. Therefore, by mixing the rutile type and the anatase type within the range specified in the present invention, the disadvantages of the rutile type and the anatase type can be compensated.
[0011]
The weight ratio between the titanium oxide fine particles and the silica fine particles (titanium oxide fine particles / silica fine particles) is specified in the range of 70/30 to 95/5. The preferred weight ratio is between 80/20 and 90/10. When the weight ratio is less than 70/30, that is, when the ratio of the titanium oxide fine particles is small, the photocatalytic effect under visible light is not practically sufficient, and when the weight ratio exceeds 95/5, that is, when the ratio of the titanium oxide fine particles is large, This causes a problem that the hardness of the obtained coating material is reduced. The silica fine particles are preferably prepared by heating and stirring a mixture of ethyl silicate, alcohol, acid and water.
The content of the titanium oxide fine particles contained in the photocatalytic paint of the present invention is preferably in the range of 0.5 to 20% by weight. If the content of the titanium oxide fine particles is less than 0.5% by weight, a sufficient photocatalytic effect cannot be obtained. If the content exceeds 20% by weight, the dispersibility of titanium oxide is reduced, and the haze of the formed photocatalytic thin film may be deteriorated. That's why. The content of the titanium oxide fine particles in the paint is more preferably in the range of 1.0 to 10.0% by weight.
[0012]
The photocatalytic coating of the present invention preferably further contains a β-diketone, a titanate-based or aluminum-based coupling agent, and an organic solvent. This is because by mixing β-diketone and a coupling agent in an organic solvent, the dispersibility of the titanium oxide fine particles is improved, the storage stability of the paint is improved, and the transparency of the obtained coating material is enhanced. It is.
Examples of the β-diketone include 2,4-pentanedione, 3-methyl-2,4-pentanedione, 3-isopropyl-2,4-pentanedione, and 2,2-dimethyl-3,5-hexanedione. Can be If β-diketone is contained at a ratio of 0.5 to 10% by weight with respect to the titanium oxide fine particles, the dispersibility is improved, so that the photocatalytic effect is further improved. It is preferable to contain it in a ratio of 1.0 to 5.0% by weight. If the content of β-diketone is less than 0.5% by weight, sufficient dispersibility cannot be obtained, and if it exceeds 10.0% by weight, further improvement in dispersibility may not be obtained.
[0013]
The coupling agent acts as a haze reducing agent. When the coupling agent is added, secondary aggregation groups are not formed in the film structure, uniform close-packing is achieved, and the smoothness of the surface is further improved, so that haze is reduced (transparency is improved). Guessed.
Examples of the aluminum-based coupling agent include an aluminate-based coupling agent having an acetoalkoxy group. As an aluminate coupling agent having an acetoalkoxy group, there is a compound represented by the following formula (1).
[0014]
Embedded image
Examples of the titanate coupling agent include a titanate coupling agent having a dialkyl pyrophosphate group or a dialkyl phosphite group. Examples of the titanate coupling agent having a dialkyl pyrophosphate group include compounds represented by the following formulas (2) to (4).
[0016]
Embedded image
Examples of the titanate-based coupling agent having a dialkyl phosphite group include compounds represented by the following formulas (5) and (6).
[0018]
Embedded image
One or more of these coupling agents can be used. The titanate-based or aluminum-based coupling agent is preferably contained at a ratio of 0.1 to 5% by weight based on the titanium oxide fine particles. The reason is that if the content of the coupling agent is less than 0.1% by weight, the effect of dispersibility and haze reduction cannot be obtained, and if the content exceeds 5.0% by weight, further haze reduction and dispersibility improvement will not be obtained. is there. Desirably, the content is 0.5 to 2.0% by weight.
[0020]
The organic solvent is preferably a single alcohol having a boiling point of 170 ° C. or lower or a mixed solvent of a plurality of alcohols. As the mixed alcohol, a mixed liquid composed of methyl alcohol and ethyl alcohol is preferable. The amount of the solvent contained in the photocatalytic coating is not particularly limited as long as a viscosity suitable for coating can be obtained.
In order to obtain the photocatalytic coating material of the present invention, first, a mixed solution is prepared by mixing a β-diketone and one or both of a titanate-based and an aluminate-based coupling agent in an organic solvent. Next, titanium oxide fine particles are mixed and dispersed in this mixed solution to prepare a dispersion of titanium oxide fine particles. Further, it can be obtained by mixing silica fine particles with this dispersion.
[0021]
The film forming method of the present invention is characterized in that the above-described photocatalyst paint of the present invention is applied on a substrate, and the applied substrate is dried. The coating method can be applied by a spin coating method, a doctor blade method, a dipping method, a brush coating, a spray method, a roll coater method or the like which has been conventionally used, but the application method is not particularly limited.
The photocatalyst paint is applied to the surface of a predetermined base material by the above-mentioned application method, for example, and dried to obtain a coating material having a photocatalytic function on the surface. Alternatively, a coating material having a photocatalytic function can be obtained by forming an inorganic base layer on the surface of the base material, applying a photocatalytic paint on the base layer, and drying to form a photocatalytic film.
[0022]
The material used for the base material of the present invention is selected from the group consisting of glass, plastic, metal, wood, ceramic including tile, cement, concrete, stone, fiber, paper and leather. Examples of the glass include indoor light purification (contaminant decomposition) glass such as fluorescent lamps and windows, water purification glass such as water tanks and cages, anti-fog glass for cars, anti-fouling glass such as CRTs, LCD screens, windows, mirrors, and glasses. , Cameras and optical equipment, and anti-mold lenses. Examples of plastics include AV equipment, computers, mice, keyboards, remote controllers, floppy disks, etc. and their peripheral products, car interiors, furniture, kitchens, baths, toilets, and other household goods. There are dirt, antibacterial and antifungal plastics. Examples of the metal include an antifouling, antibacterial, antifungal stainless steel, an antifouling, an antibacterial doorknob, and the like used for a clothesline, a clothesline, a workbench in a kitchen, a laboratory, a washing place, a ventilation fan, and the like. Wood is used for antifouling furniture, antibacterial game facilities in parks, and the like. Building materials such as ceramic, cement, concrete, and stone, including tiles, include anti-fouling treated outer wall materials, roofs, flooring materials, and other inner wall materials that have indoor environment purification (contaminant decomposition) properties, anti-fouling, antibacterial, and anti-fungal There are various processed interior products. As paper, it can be used for antibacterial treatment stationery and the like. Examples of the fiber such as a film include a transparent antibacterial film for food packaging, a transparent ethylene gas decomposition film for storing vegetables, a film for environmental and water purification, and the like. As described above, since various substrates have antifouling, environmental purification, antibacterial, and antifungal effects, any conditions that can be applied with visible light and ultraviolet light emitted from sunlight, a fluorescent lamp, or the like are used except for those described above. But it can be used for many applications. Examples of the inorganic underlayer include silica and alumina. The processed stone material, wall material or glass coated with the coating material of the present invention has excellent transparency and hardness and exhibits high decomposition performance.
[0023]
【Example】
Next, examples of the present invention will be described in detail together with comparative examples.
<Example 1>
Titanium oxide fine particles having an average particle size of 0.01 μm and a weight ratio (rutile type / anatase type) of the rutile type crystal structure to the anatase type crystal structure of 70/30 were prepared. Further, ethanol was used as an organic solvent, 2,4-pentanedione was used as a β-diketone, and a titanate coupling agent represented by the above chemical formula (2) was prepared as a coupling agent.
The organic solvent, β-diketone, coupling agent and titanium oxide were each mixed and dispersed with 100 g of zirconia beads on a paint shaker for 16 hours. The amount of β-diketone was 2.0% by weight based on titanium oxide, and the amount of coupling agent was 0.5% by weight based on titanium oxide. This dispersion was mixed with a silica fine particle-containing solution so that the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 70/30 to prepare a photocatalytic coating. TiO in prepared paint 2 The content was 0.5% by weight.
[0024]
<Example 2>
A photocatalytic paint was prepared in the same manner as in Example 1 except that the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) was set to 80/20.
<Example 3>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 1 except that the content was 1% by weight and the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 90/10.
<Example 4>
TiO in paint 2 The content was 1% by weight, the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 95/5, and a mixed solvent of 30% by weight ethanol and 70% by weight methanol was used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 1 except for the above.
<Example 5>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the solvent is 30% by weight ethanol and 70% by weight methanol. A photocatalytic paint was prepared in the same manner as in Example 1 except that a mixed solvent of was used.
<Example 6>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 80/20, and a photocatalytic coating material was prepared in the same manner as in Example 1 except that a mixed solvent of 30% by weight of ethanol and 70% by weight of methanol was used as a solvent.
[0025]
<Example 7>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 90/10, and a photocatalytic coating material was prepared in the same manner as in Example 1 except that a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
Example 8
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was changed to 95/5, and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 9>
TiO in paint 2 The content is 10% by weight, the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles is 90/10, and 50% by weight of ethanol and 50% by weight of methanol are used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 1 except that a mixed solvent of was used.
<Example 10>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 80/20, and a photocatalytic coating material was prepared in the same manner as in Example 1 except that a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 11>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 90/10, and a photocatalytic paint was prepared in the same manner as in Example 1 except that a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
[0026]
<Example 12>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 13>
TiO in paint 2 Example 1 was repeated except that the content was 15% by weight, the weight ratio of the rutile-type crystal structure to the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and methanol was used as a solvent. A photocatalytic paint was prepared in the same manner.
<Example 14>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20 and methanol was used as a solvent.
<Example 15>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic coating material was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10 and methanol was used as a solvent.
<Example 16>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles was 95/5, and methanol was used as a solvent.
[0027]
<Example 17>
A photocatalytic paint was prepared in the same manner as in Example 1 except that the average particle size of the titanium oxide fine particles was changed to 0.03 μm.
<Example 18>
A photocatalytic paint was prepared in the same manner as in Example 17, except that the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) was 80/20.
<Example 19>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 17, except that the content was 1% by weight and the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 90/10.
<Example 20>
TiO in paint 2 The content was 1% by weight, the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 95/5, and a mixed solvent of 30% by weight ethanol and 70% by weight methanol was used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 17 except for the above.
<Example 21>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the solvent is 30% by weight ethanol and 70% by weight methanol. A photocatalytic paint was prepared in the same manner as in Example 17 except that a mixed solvent of was used.
<Example 22>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic coating was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20, and a mixed solvent of 30% by weight of ethanol and 70% by weight of methanol was used as a solvent.
[0028]
<Example 23>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 90/10, and a photocatalytic coating material was prepared in the same manner as in Example 17 except that a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 24>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 25>
TiO in paint 2 The content is 10% by weight, the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles is 90/10, and 50% by weight of ethanol and 50% by weight of methanol are used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 17 except that a mixed solvent of was used.
<Example 26>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 27>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 90/10, and a photocatalytic coating material was prepared in the same manner as in Example 17 except that a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
[0029]
<Example 28>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 29>
TiO in paint 2 Example 17 except that the content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile-type / anatase-type) was 95/5, and methanol was used as the solvent. A photocatalytic paint was prepared in the same manner.
<Example 30>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic coating material was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20 and methanol was used as a solvent.
<Example 31>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10 and methanol was used as a solvent.
<Example 32>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 17 except that the ratio of titanium fine particles / silica fine particles) was changed to 95/5 and methanol was used as a solvent.
[0030]
<Example 33>
A photocatalytic paint was prepared in the same manner as in Example 1 except that the average particle size of the titanium oxide fine particles was changed to 0.04 μm.
<Example 34>
A photocatalytic coating material was prepared in the same manner as in Example 33 except that the weight ratio between the titanium oxide fine particles and the silica fine particles (titanium oxide fine particles / silica fine particles) was 80/20.
<Example 35>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 33, except that the content was 1% by weight and the weight ratio between the titanium oxide fine particles and the silica fine particles (titanium oxide fine particles / silica fine particles) was 90/10.
<Example 36>
TiO in paint 2 The content was 1% by weight, the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 95/5, and a mixed solvent of 30% by weight ethanol and 70% by weight methanol was used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 33 except for the above.
<Example 37>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the solvent is 30% by weight ethanol and 70% by weight methanol. A photocatalytic paint was prepared in the same manner as in Example 33 except that a mixed solvent of was used.
<Example 38>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 33 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20, and a mixed solvent of 30% by weight of ethanol and 70% by weight of methanol was used as a solvent.
[0031]
<Example 39>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 33, except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10, and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 40>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 33, except that the ratio of titanium fine particles / silica fine particles) was changed to 95/5, and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 41>
TiO in paint 2 The content is 10% by weight, the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles is 90/10, and 50% by weight of ethanol and 50% by weight of methanol are used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 33 except that a mixed solvent of was used.
<Example 42>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic coating material was prepared in the same manner as in Example 33, except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 43>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 33, except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10 and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
[0032]
<Example 44>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 33 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 45>
TiO in paint 2 Example 33 except that the content was 15% by weight, the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles was 95/5, and methanol was used as a solvent. Similarly, a photocatalytic coating was prepared.
<Example 46>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 33, except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20 and methanol was used as a solvent.
<Example 47>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic coating was prepared in the same manner as in Example 33 except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10 and methanol was used as a solvent.
<Example 48>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 33 except that the ratio of titanium fine particles / silica fine particles) was changed to 95/5, and methanol was used as a solvent.
[0033]
<Example 49>
A photocatalytic paint was prepared in the same manner as in Example 1, except that the average particle size of the titanium oxide fine particles was 0.05 μm.
<Example 50>
A photocatalytic paint was prepared in the same manner as in Example 49 except that the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) was 80/20.
<Example 51>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 49 except that the content was 1% by weight and the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) was 90/10.
<Example 52>
TiO in paint 2 The content was 1% by weight, the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 95/5, and a mixed solvent of 30% by weight ethanol and 70% by weight methanol was used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 49 except for the above.
<Example 53>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the solvent is 30% by weight ethanol and 70% by weight methanol. A photocatalytic paint was prepared in the same manner as in Example 49 except that a mixed solvent of was used.
<Example 54>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 80/20, and a photocatalytic coating material was prepared in the same manner as in Example 49 except that a mixed solvent of 30% by weight of ethanol and 70% by weight of methanol was used as a solvent.
[0034]
<Example 55>
TiO in paint 2 The content is 5% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was 90/10 and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 56>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 80/20, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic coating material was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 50% by weight of ethanol and 50% by weight of methanol was used as a solvent.
<Example 57>
TiO in paint 2 The content is 10% by weight, the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles is 90/10, and 50% by weight of ethanol and 50% by weight of methanol are used as a solvent. A photocatalytic paint was prepared in the same manner as in Example 49 except that a mixed solvent of was used.
<Example 58>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 59>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 49 except that the ratio of (titanium fine particles / silica fine particles) was 90/10 and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
[0035]
<Example 60>
TiO in paint 2 The content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 90/10, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 49, except that the ratio of titanium fine particles / silica fine particles) was set to 95/5, and a mixed solvent of 70% by weight of ethanol and 30% by weight of methanol was used as a solvent.
<Example 61>
TiO in paint 2 Example 49 except that the content was 15% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile-type / anatase-type) was 95/5, and methanol was used as a solvent. Similarly, a photocatalytic coating was prepared.
<Example 62>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic coating material was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was changed to 80/20 and methanol was used as a solvent.
<Example 63>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic paint was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was changed to 90/10 and methanol was used as a solvent.
<Example 64>
TiO in paint 2 The content was 20% by weight, the weight ratio between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) was 95/5, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation). A photocatalytic coating material was prepared in the same manner as in Example 49 except that the ratio of titanium fine particles / silica fine particles) was changed to 95/5, and methanol was used as a solvent.
[0036]
<Comparative Example 1>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 1 except that the content was 5% by weight and the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 65/35.
<Comparative Example 2>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 95/5, and the weight ratio of the titanium oxide fine particles to the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was changed to 65/35.
<Comparative Example 3>
TiO in paint 2 A photocatalyst was prepared in the same manner as in Example 1 except that the content was 5% by weight, and the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) was 100/0, that is, the silica fine particles were not mixed in the paint. A paint was prepared.
<Comparative Example 4>
TiO in paint 2 The content is 5% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 95/5, and the weight ratio of the titanium oxide fine particles to the silica fine particles (oxidation (Titanium fine particles / silica fine particles) was 100/0, that is, a photocatalytic coating material was prepared in the same manner as in Example 1 except that silica fine particles were not mixed into the coating material.
<Comparative Example 5>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 1 except that the content was 5% by weight and the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles was 65/35. Prepared.
[0037]
<Comparative Example 6>
TiO in paint 2 The content is 10% by weight, the weight ratio of the rutile type crystal structure to the anatase type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 65/35, and the weight ratio of the titanium oxide fine particles to the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5 and methanol was used as a solvent.
<Comparative Example 7>
TiO in paint 2 Example 1 except that the content was 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile-type / anatase-type) was 100/0, and methanol was used as the solvent. Similarly, a photocatalytic coating was prepared.
<Comparative Example 8>
TiO in paint 2 The content is 10% by weight, the weight ratio between the rutile-type crystal structure and the anatase-type crystal structure of the titanium oxide fine particles (rutile type / anatase type) is 100/0, and the weight ratio between the titanium oxide fine particles and the silica fine particles (oxidation A photocatalytic paint was prepared in the same manner as in Example 1 except that the ratio of titanium fine particles / silica fine particles) was set to 95/5 and methanol was used as a solvent.
<Comparative Example 9>
TiO in paint 2 A photocatalytic paint was prepared in the same manner as in Example 1 except that the content was 10% by weight, the average particle size of the titanium oxide fine particles was 0.06 μm, and methanol was used as a solvent.
<Comparative Example 10>
TiO in paint 2 The content is 10% by weight, the average particle size of the titanium oxide fine particles is 0.06 μm, and the weight ratio (rutile type / anatase type) between the rutile type crystal structure and the anatase type crystal structure of the titanium oxide fine particles is 95/5. A photocatalytic paint was prepared in the same manner as in Example 1 except that the weight ratio of titanium oxide fine particles to silica fine particles (titanium oxide fine particles / silica fine particles) was 95/5, and methanol was used as a solvent.
[0038]
<Comparison test and evaluation>
The photocatalyst paint prepared in each of Examples 1 to 64 and Comparative Examples 1 to 10 was applied to a glass substrate of 10 cm × 10 cm by a spin coater and dried at 150 ° C. for 1 hour to form a photocatalytic thin film on the surface of the glass substrate. A coating material was obtained.
With respect to the photocatalytic thin film of the coating material thus obtained, the haze, pencil hardness and photocatalytic activity of the photocatalytic thin film were measured. The haze was measured using a haze computer HGM-3D manufactured by Suga Test Instruments Co., Ltd. As for the photocatalytic activity, the removal rate obtained by the following procedure was used as an index of the photocatalytic activity. First, a glass substrate was put into a 1 L glass (Pyrex) container with the thin film forming surface facing upward, and the container was sealed. Next, 10 ppm (initial concentration) of acetaldehyde was introduced into the container. Next, a fluorescent lamp (trade name: National Twin 7, 27W type) was set at a distance of 20 cm above the container, and the container was irradiated with the fluorescent lamp for 2 hours. The wavelength of the light emitted from this fluorescent lamp was 410 to 810 nm. The concentration of acetaldehyde inside the container after the irradiation was measured with a gas detector tube (manufactured by Gastech), and the removal rate was determined based on the following equation.
Removal rate [%] = [(initial density-density after light irradiation) / initial density] x 100
Table 1 shows the measurement results of the photocatalytic thin films of the coating materials formed from the photocatalytic paints of Examples 1 to 64 and Comparative Examples 1 to 10, respectively.
[0039]
[Table 1]
[Table 2]
[Table 3]
As is clear from Tables 1 to 3, the thin films obtained from the photocatalytic paints of Comparative Examples 1 to 10 which are out of the range of the present invention are practically sufficient, such as low pencil hardness, large haze, and low acetaldehyde removal rate. The results were not so good. On the other hand, the thin films obtained from the photocatalyst paints of Examples 1 to 64 defined in the scope of the present invention have sufficient hardness, a small haze value, and a sufficient effect of removing acetaldehyde in practical use. It turns out that there is.
[0043]
【The invention's effect】
As described above, the photocatalytic paint of the present invention is an improvement of a paint containing titanium oxide fine particles and silica fine particles, respectively, and its characteristic configuration is that the titanium oxide fine particles have a rutile crystal structure and an anatase crystal structure. The weight ratio (rutile type / anatase type) is 70/30 to 95/5, the average particle size of the titanium oxide fine particles is 0.01 to 0.05 μm, and the weight ratio of the titanium oxide fine particles to the silica fine particles (oxidation (Titanium fine particles / silica fine particles) is 70/30 to 95/5. The coating material formed by applying the photocatalyst paint prepared as described above to a substrate and drying the applied substrate has excellent responsiveness in the visible light region and excellent transparency. Further, since the hardness of the coating material is high, the coating material is hardly damaged, and a decrease in transparency can be suppressed.
[Brief description of the drawings]
FIG. 1 is a diagram showing a relationship between a photocatalytic effect and a wavelength in each crystal structure.
Claims (9)
前記酸化チタン微粒子がルチル型結晶構造とアナターゼ型結晶構造とをその重量比（ルチル型／アナターゼ型）が７０／３０〜９５／５で含み、
前記酸化チタン微粒子の平均粒径が０．０１〜０．０５μｍであり、
前記酸化チタン微粒子と前記シリカ微粒子との重量比（酸化チタン微粒子／シリカ微粒子）が７０／３０〜９５／５である
ことを特徴とする光触媒塗料。In a photocatalytic paint containing titanium oxide fine particles and silica fine particles, respectively,
The titanium oxide fine particles include a rutile-type crystal structure and an anatase-type crystal structure in a weight ratio (rutile-type / anatase-type) of 70/30 to 95/5,
The average particle diameter of the titanium oxide fine particles is 0.01 to 0.05 μm,
A photocatalytic paint, wherein the weight ratio of the titanium oxide fine particles to the silica fine particles (titanium oxide fine particles / silica fine particles) is 70/30 to 95/5.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008279407A (en) * | 2007-05-14 | 2008-11-20 | Kanac Corp | Visible light response type titanium dioxide photocatalyst powder and its manufacturing method and device |
| JP2011519720A (en) * | 2008-05-02 | 2011-07-14 | アルチュリク・アノニム・シルケチ | Photocatalyst nanocomposite material |
| JP2019011417A (en) * | 2017-06-29 | 2019-01-24 | 日本ペイント株式会社 | Coating Composition |
| JP2019011418A (en) * | 2017-06-29 | 2019-01-24 | 日本ペイント株式会社 | Coating Composition |
-
2002
- 2002-08-29 JP JP2002250399A patent/JP2004083832A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008279407A (en) * | 2007-05-14 | 2008-11-20 | Kanac Corp | Visible light response type titanium dioxide photocatalyst powder and its manufacturing method and device |
| JP2011519720A (en) * | 2008-05-02 | 2011-07-14 | アルチュリク・アノニム・シルケチ | Photocatalyst nanocomposite material |
| JP2019011417A (en) * | 2017-06-29 | 2019-01-24 | 日本ペイント株式会社 | Coating Composition |
| JP2019011418A (en) * | 2017-06-29 | 2019-01-24 | 日本ペイント株式会社 | Coating Composition |
| JP7080592B2 (en) | 2017-06-29 | 2022-06-06 | 日本ペイント株式会社 | Paint composition |
| JP7080593B2 (en) | 2017-06-29 | 2022-06-06 | 日本ペイント株式会社 | Paint composition |
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