JP2005041942A - Luminescent substance, light emitting device using the same, lighting device using light emitting device, and image display device - Google Patents

Abstract

Kind Code: A1 A light emitting material having high emission intensity and high color rendering properties or a wide color reproduction range, and the light emitting material as a wavelength conversion material and a light emitting material that emits light in the ultraviolet to visible light range. And a lighting device and an image display device using the light emitting device as a light source.
A luminescent substance comprising a fluorescent complex in porous inorganic particles having an average pore size of 5 to 500 nm.
[Selection figure] None

Description

【００３１】
一般式（１）で表されるユーロピウム錯体の具体例（１〜７）を以下に示す。
なお、本実施の形態においてはこれらに限定されるものではない。
【００３２】
【化３】

【００３３】
次に、一般式（２）で表されるユーロピウム錯体について説明する。一般式（２）におけるルイス塩基からなる補助配位子（Ｒ_６）としては特に限定されないが、通常、ユーロピウムイオンに配位可能な窒素原子又は酸素原子を有するルイス塩基化合物から選択される。それらの例としては、置換基を有することがあるアミン、アミンオキシド、ホスフィンオキシド、スルホキシド等が挙げられる。
補助配位子として使用される２個のルイス塩基化合物は、それぞれ異なる化合物でもよく、又、２個の化合物で１つの化合物を形成していてもよい。
【００３４】
具体的には、例えば、アミンとしては、ピリジン、ピラジン、キノリン、イソキノリン、フェナントリジン、２，２’−ビピリジン、１，１０−フェナントロリン等が挙げられる。アミンオキシドとしては、ピリジン−Ｎ−オキシド、２，２’−ビピリジン−Ｎ，Ｎ’−ジオキシド等の上記アミンのＮ−オキシドが挙げられる。ホスフィンオキシドとしては、トリフェニルホスフィンオキシド、トリメチルホスフィンオキシド、トリオクチルホスフィンオキシド等が挙げられる。
スルホキシドとしては、ジフェニルスルホキシド、ジオクチルスルホキシド等が挙げられる。これらに置換する置換基としては、前述した置換基が例示される。
中でも、特に、アルキル基、アリール基、アルコシキル基、アラルキル基、アリールオキシ基、ハロゲン基等が好ましい。
【００３５】
これらのルイス塩基化合物の中でも、ビピリジンやフェナントロリン等のように、分子内に配位する原子、例えば窒素原子等の２個存在する場合は、１つのルイス塩基化合物で２個の補助配位子と同様な働きをさせてもよい。なお、これらのルイス塩基化合物に置換する置換基としては、前述した置換基が例示される。
中でも、特に、アルキル基、アリール基、アルコシキル基、アラルキル基、アリールオキシ基、ハロゲン基等が好ましい。
【００３６】
補助配位子として使用するルイス塩基化合物（Ｒ_６）の具体例（１〜２３）を以下に例示する。なお、本実施の形態において使用するルイス塩基化合物は、これらに限定されるものではない。
【００３７】
【化４】

【００３８】
一般式（２）で表されるユーロピウム錯体の具体例（１〜１３）を以下に示す。なお、本実施の形態においてはこれらに限定されるものではない。
【００３９】
【化５】

【００４０】
次に、一般式（３）で表されるユーロピウム錯体について説明する。一般式（３）におけるアンモニウムイオンとしては、アルキルアミン、アリールアミン、アラルキルイオンから誘導される４級アンモニウム塩が挙げられる。アミンの置換基としては、メチル、エチル、プロピル、ブチル、ヘキシル、オクチル等のアルキル基；ヒドロキシエチル、メトキシエチル等の置換アルキル基；フェニル、トリル等のアリール基；ベンジル、フェネチル基等のアリールアルキル基等が挙げられる。
【００４１】
一般式（３）で表されるユーロピウム錯体の具体例（１〜５）を以下に示す。なお、本実施の形態においてはこれらに限定されるものではない。
【００４２】
【化６】

【００４３】
希土類イオン錯体のもう一つの化合物である、芳香族基を含む置換基を有するカルボン酸イオンを配位子とする錯体としては、例えば、下記一般式（４）で表されるユーロピウム錯体が挙げられる。
【００４４】
【化７】
（Ｒ_８−（Ｘ）_ｎ−ＣＯＯ）_３Ｅｕ（Ｒ_９）_２ （４）
（式中、Ｒ_８は、置換基を有することがある芳香族炭化水素環又は芳香族複素環を少なくとも１つ含む基であり、Ｘは、２価の連結基であり、ｎは、０又は１であり、Ｒ_９は、ルイス塩基からなる補助配位子である。）
一般式（４）で表される配位子は、芳香族環を少なくとも１つ含み、π電子を８個以上有し、π電子共役系を構成するカルボン酸イオンを配位子として用いることが、吸収波長域の点から好ましい。又、芳香族環の個数は、カルボン酸イオンの母体化合物の三重項エネルギーが、ユーロピウムイオン励起状態エネルギーレベルよりも高いものであれば特に制限されないが、通常、３環式以下の芳香族又は芳香族複素環を用いることが好ましい。芳香族環の個数が４環以上の場合は、例えば、芳香族環を４環以上有するピレン等の化合物は、第１の発光体からの光を吸収して励起された三重項エネルギーが低くなり、ユーロピウム錯体が発光しなくなるおそれがある。
【００４５】
一般式（４）中のＲ_８は、置換基を有することがある３環式以下の芳香族環、又は複素芳香族環から誘導される１価の基であることが好ましい。芳香族環としては、例えば、ベンゼン、ナフタリン、インデン、ビフェニレン、アセナフテン、フルオレン、フェナントレン、テトラリン、インダン、インデン等の芳香族単環式炭化水素又は芳香族縮合多環式炭化水素；ベンゾキノン、ナフトキノン、アントラキノン等の芳香族炭化水素から誘導される化合物等が挙げられる。複素芳香族環としては、フラン、ピロール、チオフェン、オキサゾール、イソキサゾール、チアゾール、イミダゾール、ピリジン、ベンゾフラン、ベンゾチオフェン、クマリン、ベンゾピラン、カルバゾール、キサンテン、キノリン、トリアジン等の芳香族単環式複素環又は芳香族縮合多環式複素環等が挙げられる。
【００４６】
また、Ｒ_８が有することがある置換基としては、メチル、エチル、プロピル、ブチル等のアルキル基；トリフルオロメチル、ペンタフルオロエチル等のフルオロアルキル基；シクロヘキシル基等のシクロアルキル基；エチニル基；フェニルエチニル、ピリジルエチニル、チエニルエチニル等のアリールエチニル基；メトキシ、エトキシ等のアルコキシ基；フェニル、ナフチル等のアリール基；ベンジル、フェネチル等のアラルキル基；フェノキシ、ナフトキシ、ビフェニルオキシ等のアリールオキシ基；ヒドロキシル基；アリル基；アセチル、プロピオニル、ベンゾイル、トルオイル、ビフェニルカルボニル等のアシル基；アセトキシ、プロピオニルオキシ、ベンゾイルオキシ等のアシルオキシ基；メトキシカルボニル、エトキシカルボニル等のアルコキシカルボニル基；フェノキシカルボニル等のアリールオキシカルボニル基；カルボキシル基；カルバモイル基；アミノ基；ジメチルアミノ、ジエチルアミノ、メチルベンジルアミノ、ジフェニルアミノ、アセチルメチルアミノ等の置換アミノ基；メチルチオ、エチルチオ、フェニルチオ、ベンジルチオ等の置換チオ基；メルカプト基；エチルスルフォニル、フェニルスルフォニル基等の置換スルフォニル基；シアノ基；フルオロ、クロロ、ブロモ、ヨード等のハロゲン基等が挙げられる。これらの中でも、アルキル基、アルコキシ基、アリール基、シクロアルキル基、シクロアルキル基、アリールオキシ基、アラルキル基、エチニル基、ハロゲン基が好ましい。尚、Ｒ_８は、これらの置換基に限定するものではない。また、これらの置換基はさらに置換基を有することがある。
【００４７】
次に、一般式（４）におけるカルボン酸イオンは、２価の連結基であるＸを有さない場合（ｎ＝０）と有する場合（ｎ＝１）とに分けられる。更に、２価の連結基であるＸを有する場合（ｎ＝１）、Ｘは、カルボニル基を有する場合及び有さない場合の２種類の形態に分けられる。このため一般式（４）におけるカルボン酸イオンは、さらに、カルボニル基を有さない下記一般式（５）とカルボニル基を有する一般式（６）とで表される。ユーロピウム錯体は、これらのカルボン酸イオンを配位子とする錯体構造のいずれもが使用することができる。
【００４８】
【化８】

【００４９】
一般式（５）及び一般式（６）中、Ｒ_１０は、２価の連結基となるものであればよいが、例えば、アルキレン基、環集合炭化水素から誘導される２価の連結基、脂肪族環、芳香族環、複素環から誘導される２価の連結基等が挙げられる。また、一般式（６）中、ｍは０又は１である。Ｒ_１０の、アルキレン基としては、メチレン、エチレン等が挙げられる。環集合炭化水素としては、ビフェニル、テルフェニル、ビナフチル、シクロヘキシルベンゼン、フェニルナフタレン等が挙げられる。脂肪族環としては、シクロペンタン、シクロヘキサン、シクロヘプタン、ノルボルナン、ビシクロヘキシル等が挙げられる。芳香族環としては、前述した芳香族環の具体例と同様な化合物が挙げられる。複素環としては、前述した芳香族複素環の他に、ピラゾリン、ピペラジン、イミダゾリジン、モルホリン等の脂肪族複素環が挙げられる。その他、−ＳＣＨ_２−等のチオアルキレン；−ＯＣＨ_２−等のオキシアルキレン；ビニレン（−Ｃ＝Ｃ−）等が挙げられる。尚、Ｒ_１０は、これらの２価の置換基に限定するものではない。また、これらの２価の置換基はさらに置換基を有することがある。
【００５０】
一般式（４）におけるカルボン酸イオンが誘導されるカルボン酸の具体例を以下に例示する。なお、本実施の形態において使用するカルボン酸は、これらに限定されるものではない。一般式（４）においてｎが０の場合の化合物は、以下のカルボン酸（１〜１０）が挙げられる。
【００５１】
【化９】

【００５２】
次に、一般式（４）においてｎが１であり、ＸがＲ_１０である場合（一般式（５））の化合物は、以下のカルボン酸（１１〜１５）が挙げられる。
【００５３】
【化１０】

【００５４】
次に、一般式（６）において、ｍが０の場合の化合物は、以下のカルボン酸（１６及び１７）が挙げられる。
【００５５】
【化１１】

【００５６】
一般式（６）において、ｍが１の場合であって、Ｒ_８がフェニル基、Ｒ_１０がフェニル基の場合の化合物は、以下のカルボン酸（１８〜３０）が挙げられる。
【００５７】
【化１２】

【００５８】
一般式（６）において、ｍが１の場合であって、Ｒ_８がフェニル基、Ｒ_１０がナフチル基の場合の化合物は、以下のカルボン酸（３１〜３４）が挙げられる。
【００５９】
【化１３】

【００６０】
一般式（６）において、ｍが１の場合であって、Ｒ_８がフェニル基、Ｒ_１０がその他の基の場合の化合物は、以下のカルボン酸（３５〜３７）が挙げられる。
【００６１】
【化１４】

【００６２】
一般式（６）において、ｍが１の場合であって、Ｒ_８がナフチル基、Ｒ_１０が芳香族環の場合の化合物は、以下のカルボン酸（３８〜４１）が挙げられる。
【００６３】
【化１５】

【００６４】
一般式（６）において、ｍが１の場合であって、Ｒ_８がナフチル基、Ｒ_１０がその他の基の場合の化合物は、以下のカルボン酸（４２〜４４）が挙げられる。
【００６５】
【化１６】

【００６６】
一般式（６）において、ｍが１の場合であって、Ｒ_８がアセナフチル基、Ｒ_１０がフェニル基その他の場合の化合物は、以下のカルボン酸（４５〜４８）が挙げられる。
【００６７】
【化１７】

【００６８】
一般式（６）において、ｍが１の場合であって、Ｒ_８がフルオレニル基、Ｒ_１０がフェニル基の場合の化合物は、以下のカルボン酸（４９〜５５）が挙げられる。
【００６９】
【化１８】

【００７０】
一般式（６）において、ｍが１の場合であって、Ｒ_８がフェナントレニル基、Ｒ_１０がフェニル基その他の場合の化合物は、以下のカルボン酸（５６〜５９）が挙げられる。
【００７１】
【化１９】

【００７２】
一般式（６）において、ｍが１の場合であって、Ｒ_８が複素環基、Ｒ_１０がフェニル基の場合の化合物は、以下のカルボン酸（６０及び６１）が挙げられる。
【００７３】
【化２０】

【００７４】
一般式（４）における配位子としてのカルボン酸イオンが誘導されるカルボン酸は、公知の合成方法により合成することが出来る。合成法については、例えば、新実験化学講座第１４巻「有機化合物の合成と反応（ＩＩ）」第９２１頁（１９７７）日本化学会編、又は、第４版実験化学講座第２２巻「有機合成ＩＶ」第１頁（１９９２）日本化学会編等に記載されている。代表的な合成法としては、対応する第１アルコールやアルデヒドの酸化反応、エステルやニトリルの加水分解反応、酸無水物によるフリーデル・クラフツ反応等が挙げられる。
【００７５】
特に、無水フタル酸、ナフタル酸無水物、無水こはく酸、ジフェン酸無水物、１，２−シクロヘキサンジカルボン酸無水物、２，３−ピリダジンジカルボン酸無水物等のジカルボン酸の環状無水物を用いたフリーデル・クラフツ反応では、分子内にカルボニル基を有するカルボン酸が合成できる。例えば、芳香族炭化水素又は芳香族複素環と無水フタル酸とを用いたフリーデル・クラフツ反応によれば、下記反応式に示すように、ベンゼン環のオルト位にカルボニル基が結合したカルボン酸が容易に合成できる。ベンゼン環のオルト位にカルボニル基が結合したカルボン酸は、パラ位置換体に比べ輝度が高い錯体が得られやすいことから好ましい。尚、式中、Ａｒは、芳香族炭化水素又は芳香族複素環を表す。
【００７６】
【化２１】

【００７７】
一般式（４）におけるルイス塩基からなる補助配位子（Ｒ_９）としては、前述した一般式（２）におけるルイス塩基からなる補助配位子（Ｒ_６）と同様な化合物が挙げられる。
また、本発明において発光物質は第２の発光体として、第１の発光体からの３５０−４１５ｎｍの光によって励起され、可視光を発生する。上記発光物質は、３５０−４１５ｎｍの光の励起によって演色性がよく、かつ、強い発光強度の可視光を発生する。特に、第１の発光体としてのＧａＮ系半導体から発せられる４００ｎｍ励起光により演色性が高く、かつ輝度が高い蛍光を発することを発見したものである。
【００７８】
本発明において、前記蛍光体を照明装置や画像表示装置などの発光装置に好適に用いることができる。光を照射する第１の発光体は、波長３５０−４１５ｎｍの光を発生する。好ましくは波長３５０−４１５ｎｍの範囲にピーク波長を有する光を発生する発光体を使用する。第１の発光体の具体例としては、発光ダイオード（ＬＥＤ）またはレーザーダイオード（ＬＤ）等を挙げることができる。消費電力が良く少ない点でより好ましくはレーザーダイオードである。その中で、ＧａＮ系化合物半導体を使用した、ＧａＮ系ＬＥＤやＬＤが好ましい。なぜなら、ＧａＮ系ＬＥＤやＬＤは、この領域の光を発するＳｉＣ系ＬＥＤ等に比し、発光出力や外部量子効率が格段に大きく、前記蛍光体と組み合わせることによって、非常に低電力で非常に明るい発光が得られるからである。例えば、２０ｍＡの電流負荷に対し、通常ＧａＮ系はＳｉＣ系の１００倍以上の発光強度を有する。ＧａＮ系ＬＥＤやＬＤにおいては、Ａｌ_ＸＧａ_ＹＮ発光層、ＧａＮ発光層、またはＩｎ_ＸＧａ_ＹＮ発光層を有しているものが好ましい。ＧａＮ系ＬＥＤにおいては、それらの中でＩｎ_ＸＧａ_ＹＮ発光層を有するものが発光強度が非常に強いので、特に好ましく、ＧａＮ系ＬＤにおいては、Ｉｎ_ＸＧａ_ＹＮ層とＧａＮ層の多重量子井戸構造のものが発光強度が非常に強いので、特に好ましい。なお、上記においてＸ＋Ｙの値は通常０．８〜１．２の範囲の値である。ＧａＮ系ＬＥＤにおいて、これら発光層にＺｎやＳｉをドープしたものやドーパント無しのものが発光特性を調節する上で好ましいものである。ＧａＮ系ＬＥＤはこれら発光層、ｐ層、ｎ層、電極、および基板を基本構成要素としたものであり、発光層をｎ型とｐ型のＡｌ_ＸＧａ_ＹＮ層、ＧａＮ層、またはＩｎ_ＸＧａ_ＹＮ層などでサンドイッチにしたヘテロ構造を有しているものが発光効率が高く、好ましく、さらにヘテロ構造を量子井戸構造にしたものが発光効率がさらに高く、より好ましい。
【００７９】
本発明においては、面発光型の発光体、特に面発光型ＧａＮ系レーザーダイオードを第１の発光体として使用することは、発光装置全体の発光効率を高めることになるので、特に好ましい。面発光型の発光体とは、膜の面方向に強い発光を有する発光体であり、面発光型ＧａＮ系レーザーダイオードにおいては、発光層等の結晶成長を制御し、かつ、反射層等をうまく工夫することにより、発光層の縁方向よりも面方向の発光を強くすることができる。面発光型のものを使用することによって、発光層の縁から発光するタイプに比べ、単位発光量あたりの発光断面積が大きくとれる結果、第２の発光体の蛍光体にその光を照射する場合、同じ光量で照射面積を非常に大きくすることができ、照射効率を良くすることができるので、第２の発光体である蛍光体からより強い発光を得ることができる。
【００８０】
第１の発光体として面発光型のものを使用する場合、第２の発光体を膜状とするのが好ましい。その結果、面発光型の発光体からの光は断面積が十分大きいので、第２の発光体をその断面の方向に膜状とすると、第１の発光体からの蛍光体への照射断面積が蛍光体単位量あたり大きくなるので、蛍光体からの発光の強度をより大きくすることができる。
【００８１】
また、第１の発光体として面発光型のものを使用し、第２の発光体として膜状のものを用いる場合、第１の発光体の発光面に、直接膜状の第２の発光体を接触させた形状とするのが好ましい。ここでいう接触とは、第１の発光体とと第２の発光体とが空気や気体を介さないでぴたりと接している状態をつくることを言う。その結果、第１の発光体からの光が第２の発光体の膜面で反射されて外にしみ出るという光量損失を避けることができるので、装置全体の発光効率を良くすることができる。
【００８２】
第１の発光体からの光や第２の発光体からの光は通常四方八方に向いているが、第２の発光体の蛍光体の粉を樹脂中に分散させると、光が樹脂の外に出る時にその一部が反射されるので、ある程度光の向きを揃えられる。従って、効率の良い向きに光をある程度誘導できるので、第２の発光体として、前記蛍光体の粉を樹脂中へ分散したものを使用するのが好ましい。また、蛍光体を樹脂中に分散させると、第１の発光体からの光の第２の発光体への全照射面積が大きくなるので、第２の発光体からの発光強度を大きくすることができるという利点も有する。この場合に使用できる樹脂としては、エポキシ樹脂、ポリビニル系樹脂、ポリエチレン系樹脂、ポリプロピレン系樹脂、ポリエステル系樹脂等各種のものが挙げられるが、蛍光体粉の分散性が良い点で好ましくはエポキシ樹脂である。第２の発光体の粉を樹脂中に分散させる場合、当該第２の発光体の粉と樹脂の全体に対するその粉の重量比は、通常１０〜９５％、好ましくは２０〜９０％、さらに好ましくは３０〜８０％である。蛍光体が多すぎると粉の凝集により発光効率が低下することがあり、少なすぎると今度は樹脂による光の吸収や散乱のため発光効率が低下することがある。
【００８３】
本発明が適用される発光装置において使用する第２の発光体である発光物質が、第１の発光体からの光に対して実質的に３５０ｎｍ以下の光から遮蔽されることが好ましく、例えば、▲１▼発光体と発光物質の間に、実質的に３５０ｎｍ以下の紫外光を吸収する紫外線吸収物質を含有する紫外線吸収層を設け、３５０ｎｍ以下の光を遮断する方法、▲２▼３５０ｎｍ以下の波長光を実質的に発光しない、ＬＥＤやＬＤからなる半導体発光体を光源として用いる方法が挙げられる。
【００８４】
また、外光からの紫外光に対しては、発光物質と外光との間に紫外線吸収層を設け外光の紫外線を遮断する方法が挙げられる。この場合には、発光物質に対して発光体からの光を遮蔽しないように配置することが必要である。また、外光からの紫外光は、蛍光性錯体以外に共存する樹脂などの有機化合物の光劣化対策も考慮すると、４００ｎｍ以下の紫外光を遮蔽することが望ましい。
【００８５】
本発明が適用される発光装置において、発光体としてＬＥＤ、ＬＤを使用する場合は、発光体素子の上側に、蛍光性錯体を含有する発光物質を樹脂に混合又は分散させた樹脂組成物による被膜の蛍光体層を形成するか、ＬＥＤ、ＬＤを覆うエポキシ樹脂等の封止樹脂中に蛍光体を混合又は分散させて配置する。前者の場合は、発光物質層の上部に紫外線吸収層を積層するか、発光物質層上部に設けられる封止樹脂中に紫外線吸収物質を含有させることにより、外光からの紫外線を遮断できる。又、後者の場合は、例えば、発光体及び発光物質を内部に備えた封止樹脂体の外側を覆うように、紫外線吸収層を形成する。いずれも、発光物質や樹脂が劣化を受けるおそれがある４００ｎｍ以下の波長域の外光からの紫外光が遮蔽され、極めて良好な耐光堅牢度を得ることが出来る。
【００８６】
さらに、ガラス又は樹脂ガラス等の光透過性材料を用いたランプ型の発光装置の場合、ランプ容器に用いる光透過性材料に紫外線吸収剤を混合する、ランプ容器の外側又は内側に紫外線吸収層を設ける等の紫外線吸収処理を施すことにより、蛍光体に３５０ｎｍ以下、好ましくは４００ｎｍ以下の波長の紫外線をカットすることが出来る。ランプ型発光装置の場合、さらに、ランプ内部を真空又は不活性ガス置換により低酸素濃度雰囲気にすることで、耐光性は飛躍的に向上させることが可能となる。酸素濃度としては、１０００ｐｐｍ以下、好ましくは１００ｐｐｍ以下、より好ましくは２０ｐｐｍ以下である。
【００８７】
本発明の発光装置は、波長変換材料としての前記発光物質と、３５０−４１５ｎｍの光を発生する発光素子とから構成されてなり、前記発光物質が発光素子の発する３５０−４１５ｎｍの光を吸収して、使用環境によらず演色性が良く、かつ、高強度の可視光を発生させることのできる発光装置であり、バックライト光源、信号機などの発光源、又、カラー液晶ディスプレイ等の画像表示装置や面発光等の照明装置等の光源に適している。
【００８８】
【実施例】
以下、本発明を実施例によりさらに具体的に説明するが、本発明はその要旨を越えない限り以下の実施例に限定されるものではない。
シリカ粒子の分析方法及びアミン処理方法、ならびに蛍光体とした場合の特性評価方法を以下に記す。
１）シリカ粒子の平均ポアサイズ
窒素ガス吸脱着法で測定した等温脱着曲線から、Ｅ．Ｐ．Ｂａｒｒｅｔｔ，Ｌ．Ｇ．Ｊｏｙｎｅｒ，Ｐ．Ｈ．Ｈａｋｌｅｎｄａ，Ｊ．Ａｍｅｒ．Ｃｈｅｍ．Ｓｏｃ．，ｖｏｌ．７３，３７３（１９５１）に記載のＢＪＨ法により算出。
２）シリカ粒子の平均粒子径
ＨＯＲＩＢＡ製粒度分布計ＬＡ−９２０を用いて測定した。
【００８９】
３）シリカ粒子のポア体積、比表面積
カンタクローム社製ＡＳ−１にてＢＥＴ窒素吸着等温線を測定し、ポア体積、比表面積を求めた。具体的にはポア体積は相対圧Ｐ／Ｐ_０＝０．９８のときの値を採用し、比表面積はＰ／Ｐ_０＝０．１，０．２，０．３の３点の窒素吸着量よりＢＥＴ多点法を用いて算出した。また、ＢＪＨ法で細孔分布曲線及び最頻直径（Ｄｍａｘ）における微分細孔容積を求めた。測定する相対圧の各点の間隔は０．０２５とした。
【００９０】
４）シリカ粒子の金属不純物の含有量
シリカ粒子２．５ｇにフッ酸を加えて加熱し、乾涸させたのち、水を加えて５０ｍｌとした。この水溶液を用いてＩＣＰ発光分析を行った。なお、ナトリウム及びカリウムはフレーム炎光法で分析した。
５）粉末Ｘ線回折
理学電機社製ＲＡＤ−ＲＢ装置を用い、ＣｕＫαを線源として測定を行った。発散スリット１／２ｄｅｇ、散乱スリット１／２ｄｅｇ、受光スリット０．１５ｍｍとした。
【００９１】
６）アミン処理
５０ｍｌナスフラスコに、アミノプロピルトリエトキシシラン０．１５ｇおよびエタノール１０ｇを仕込み、室温にて１５分撹拌後、メソポーラスシリカ３ｇを添加した。室温にて３０時間撹拌後、シリカ粒子を濾別し、エタノールにて充分に洗浄した。得られたシリカ粒子を、５０℃にて６時間加熱し、その後、室温にて３日間放置し、硬化を行った。その後、減圧乾燥を行い、表面にアミノプロピル基が導入されたシリカ粒子を得た。−ＮＨ_２呈色試薬であるニンヒドリンで呈色（アミノ基の存在確認）を確認した。
【００９２】
７）蛍光性錯体含有量
蛍光性錯体挿入後の重量増加より算出した。
８）輝度測定
日立の蛍光分光測定装置Ｆ−４５００を用いた。粉体用ホルダー（日立計測器サービス社製粉末セル（蛍光））に約２００ｍｇの粉を詰め、励起波長としては４００ｎｍを用い、蛍光輝度は発光ピークの６１０ｎｍでのピーク強度の値を無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ；Ｅｕの値を１００として示した。
【００９３】
（実施例１）
シリカ粒子として、三菱化学製のメソポーラスシリカ（平均ポアサイズ；７ｎｍ、平均粒子径；３μｍ、比表面積；６８５ｍ^２／ｇ、ポア体積；１．０ｃｃ／ｇ、）を用いた。シリカ粒子の不純物濃度は、ナトリウム０．２ｐｐｍ、カリウム０．１ｐｐｍ、カルシウム０．２ｐｐｍで、マグネシウム、アルミニウム、チタン及びジルコニウムは検出されなかった。また、粉末Ｘ線回折測定を行ったところ、粉末Ｘ線回折図には結晶性のピークは出現しておらず、また周期的構造による低角度側（２θ≦５ｄｅｇ）のピークも認められなかった。このメソポーラスシリカを上述の通り、アミン処理した。下記構造式で表されるＥｕ錯体（Ｅｕ（ＴＴＡ）_３Ｐｈｅｎ錯体）０．２ｇをＴＨＦ４０ｃｃに溶解させ、アミン処理したシリカ粒子１．０ｇを混合して一昼夜攪拌した。４０℃に加温して溶媒を揮散させ、更に、室温で５ｈｒ真空脱気して発光物質を得た。
【００９４】
Ｅｕ錯体の挿入量としては、１６．５ｗｔ％であり、蛍光分光測定による４００ｎｍ励起時の発光輝度は無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ：Ｅｕの値を１００として９００であった。
【００９５】
【化２２】

【００９６】
（実施例２）
Ｅｕ（ＴＴＡ）_３Ｐｈｅｎ錯体の量を０．４ｇとしたこと以外は実施例１と同様にして発光物質を得た。Ｅｕ錯体の挿入量としては、２８．５ｗｔ％であり、蛍光分光測定による４００ｎｍ励起時の発光輝度は無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ：Ｅｕの値を１００として１１００であった。
（実施例３）
Ｅｕ（ＴＴＡ）_３Ｐｈｅｎ錯体の量を１．０ｇとしたこと以外は実施例１と同様にして発光物質を得た。Ｅｕ錯体の挿入量としては、５０．０ｗｔ％であり、蛍光分光測定による４００ｎｍ励起時の発光輝度は無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ：Ｅｕの値を１００として２１００であった。
（実施例４）
Ｅｕ（ＴＴＡ）_３Ｐｈｅｎ錯体の代わりに、下記構造式で表されるＥｕ（ＤＢＭ）_３Ｐｈｅｎ錯体０．１ｇを用いたこと以外は実施例１と同様にして発光物質を得た。
【００９７】
Ｅｕ錯体の挿入量としては、１０．０ｗｔ％であり、蛍光分光測定による４００ｎｍ励起時の発光輝度は無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ：Ｅｕの値を１００として１０００であった。
【００９８】
【化２３】

【００９９】
（比較例１）
シリカ粒子として、三菱化学製のメソポーラスシリカ（平均ポアサイズ；４ｎｍ、平均粒子径；３００μｍ、比表面積；８５０ｍ^２／ｇ、ポア体積；０．８８ｃｃ／ｇ）を用いた。シリカ粒子の不純物濃度は、ナトリウム０．２ｐｐｍ、カリウム０．１ｐｐｍ、カルシウム０．２ｐｐｍで、マグネシウム、アルミニウム、チタン及びジルコニウムは検出されなかった。また、粉末Ｘ線回折測定を行ったところ、粉末Ｘ線回折図には結晶性のピークは出現しておらず、また周期的構造による低角度側（２θ≦５ｄｅｇ）のピークも認められなかった。このメソポーラスシリカを上述の通り、アミン処理した。Ｅｕ（ＤＢＭ）_３Ｐｈｅｎ錯体０．１ｇをＴＨＦ４０ｃｃに溶解させ、アミン処理した上記シリカ粒子１．０ｇを混合して一昼夜攪拌した。４０℃に加温して溶媒を揮散させ、更に、室温で５ｈｒ真空脱気して目的物を得た。Ｅｕ錯体の挿入量としては、１０ｗｔ％であり、蛍光分光測定による４００ｎｍ励起時の発光輝度は無機赤色蛍光物質Ｙ_２Ｏ_２Ｓ：Ｅｕの値を１００として７００であった。
【０１００】
【発明の効果】
本発明によれば、演色性が高く、かつ発光強度の高い発光物質およびそれを用いた発光装置、照明装置、画像表示装置を提供することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light-emitting substance and a light-emitting device using the same, and more specifically, a first light emitter that emits light in a visible light region from 350 to 415 nm by a power source and the ultraviolet light to visible light region. Combined with a second phosphor as a wavelength conversion material that has a phosphor that becomes a luminescent substance that absorbs light and emits visible light having a longer wavelength than that light, color rendering is good regardless of the usage environment and color reproduction. The present invention relates to a light-emitting substance that can generate light having a wide range and high intensity, a light-emitting device using the light-emitting substance, and an illumination device and an image display device using the light-emitting material.
[0002]
[Prior art]
Light emission in which the emission color of LED or LD is converted with phosphor to generate various colors such as white, nonuniformity, color rendering and wide color reproduction range by mixing blue, red and green. A device has been proposed. For example, Japanese Patent Publication No. 49-1221 discloses a laser beam that emits a radiation beam having a wavelength of 300 to 530 nm as a phosphor (Y_3-xyCe_xGd_yM_5-zGa_zO₁₂(Y represents Y, Lu, or La, and M represents Al, Al—In, or Al—Sc)), and this is emitted to form a display. Further, in recent years, a white light emitting device configured by combining a gallium nitride (GaN) LED or LD with high luminous efficiency, which has been attracting attention as a blue light emitting semiconductor light emitting element, and a phosphor as a wavelength conversion material. However, it has been proposed as a light-emitting source for lighting devices and image display devices, taking advantage of the feature of low power consumption and long life. Actually, Japanese Patent Application Laid-Open No. 10-242513 discloses a light emitting device using this nitride semiconductor LED or LD chip and using yttrium, aluminum, garnet as a phosphor. . Further, in US Pat. No. 6,278,135, in a light emitting device in which a phosphor emits visible light upon receiving ultraviolet light from an LED, BaMg is used as the phosphor.₂Al₁₆O₂₇: Eu²⁺Inorganic phosphors such as are shown.
[0003]
However, so far, the first illuminant such as an LED or the like emits light such as a combination of an yttrium / aluminum / garnet phosphor as disclosed in JP-A-10-242513 as the second illuminant. In the device, it is not possible to increase the light intensity and at the same time enhance the color rendering or widen the color reproduction range, and use the lighting device that uses the light emitting device and the display as a backlight light source. Further improvement is demanded for image display devices.
[0004]
Moreover, the white light in the fluorescent lamp is realized by a combination of fluorescence emitted from three color inorganic phosphors. Inorganic phosphors that emit light efficiently with excitation light near 400 nm emitted from GaN-based LEDs with high efficiency include green phosphors such as ZnS: Cu, Al, and BaMgAl.₁₀O₁₇: Blue phosphors such as Eu have been found. However, an inorganic phosphor that efficiently emits red light has not been developed.₂O₂Even in the S: Eu phosphor, the emission intensity is insufficient. As a result, when blue, green, and red are combined, high brightness white light cannot be obtained, which hinders practical use of highly efficient white solid state lighting.
[0005]
The red light of the inorganic red phosphor is due to the emission of Eu ions. The same emission spectrum is also observed with Eu complex dyes, and it is known that the emission spectrum width is narrower and the emission intensity is much higher than the fluorescence of ordinary organic dyes. If it can be used as a fluorescent material, a white light source for solid-state illumination should be realized.
[0006]
However, the conventional Eu complex dyes are mainly used for microanalysis, mainly bio-related. Therefore, although research on improving luminance has been actively conducted, the necessity for durability is low, so light resistance is low. Almost no improvement has been made, and known Eu complex dyes cannot be put into practical use as phosphors for illumination.
In addition, to improve durability, the Eu complex dye has a pore size of 4.1 nm and a specific surface area of 600 to 800 m.²There are known examples (QinghongXu, Liansheng Li, Xinsheng Liu, Chemistry of Materials., Vol. 14, pp 549-555, 2002) that are inserted into crystalline silica particles that are / g. It was about 8 wt%, and sufficient luminance was not obtained.
[0007]
[Patent Document 1]
Japanese Patent Publication No.49-1221
[Patent Document 2]
Japanese Patent Laid-Open No. 10-242513
[Patent Document 3]
US Pat. No. 6,278,135
[Non-Patent Document 1]
Qinghong Xu, Liansheng Li, Xinsheng Liu, Chemistry of Materials. , Vol. 14, pp 549-555, 2002
[0008]
[Problems to be solved by the invention]
In view of the above-described prior art, the present invention provides a light emitting material having high emission intensity and high color rendering properties or a wide color reproduction range, a light emitting device using the same, and an illumination device or an image using the same. The object is to obtain a display device.
[0009]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a light-emitting substance containing a fluorescent complex in porous inorganic particles having a specific pore diameter can achieve the above object, and have reached the present invention. Accordingly, the present invention provides a luminescent material comprising a fluorescent complex in porous inorganic particles having an average pore size of 5 to 500 nm, and the luminescent material as a wavelength converting material, and ultraviolet light to visible light. The gist of the present invention is a light emitting device that includes a light emitter that emits light in a range, and an illumination device and an image display device that use the light emitting device as a light source.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a luminescent material containing a fluorescent complex in porous inorganic particles having an average pore size of 5 to 500 nm, a luminescent device using the luminescent material, an illuminating device having the luminescent device, and an image display device It is.
The material of the porous inorganic particles used in the present invention is SiO.₂TiO₂, Al₂O₃, ZrO₂Inorganic oxides such as these and mixtures thereof can be used, but silica can be preferably used.
[0011]
The porous inorganic particles used in the present invention have an average pore size of 5 to 500 nm, preferably 5 to 100 nm, more preferably 5 to 50 nm. When the average pore size is too small, it tends to be difficult to insert a large amount of the fluorescent complex into the porous inorganic particles. On the other hand, if it is too large, the durability tends to decrease due to the deterioration of the fluorescent complex due to the intrusion of a solvent, moisture or the like. Moreover, when it is going to disperse | distribute a fluorescent complex in resin etc., the fluorescent complex once inserted with the solvent may come out outside.
[0012]
Therefore, in order to keep the fluorescent complex inside the porous inorganic particle, it is preferable that the fluorescent complex is bonded to the porous inorganic particle. For example, when mesoporous silica is used as the porous inorganic particle, the mesoporous silica In order to connect to the inside of the mesopore, it is preferable that an amino group capable of coordinating with a metal ion such as an Eu complex is formed on the surface of the mesoporous silica and the fluorescent complex is bonded to the silica particles.
That is, the surface of mesoporous silica using a silane coupling agent such as aminopropyltriethoxysilane, aminopropyltrimethoxysilane, aminoethyltriethoxysilane, aminoethyltrimethoxysilane, aminobutyltriethoxysilane, aminobutyltrimethoxysilane, etc. In the present invention, porous inorganic particles that have been treated to introduce a functional group such as an aminopropyl group on the surface of the silica particles are preferably employed. Here, the silane coupling agent has a composition formula: (R₁) -Si- (R₂) (R₃) (R₄) And R₁Is an organic chain containing at least one functional group capable of coordinating to a metal cation such as an amino group or a carboxyl group, and R₂, R₃, R₄Is the composition formula OCH₃A methoxy group represented by the formula OCH₂CH₃An ethoxy group represented by
[0013]
The porous inorganic particles of the present invention have an average particle diameter in the range of 1 to 300 μm, preferably 1 to 50 μm, more preferably 1 to 20 μm. When it is too small, handling is difficult, and when it is too large, the coated surface becomes uneven when coated, and uniform light emission is difficult to obtain.
Further, when the porous inorganic particles of the present invention are silica particles, the pore volume and the specific surface area are in a range larger than usual, and the pore volume is 0.6 as measured by a nitrogen gas absorption / desorption method. -1.6 ml / g, preferably 0.8-1.6 ml / g. When the pore volume is small, the insertion amount of the fluorescent complex is small and does not satisfy the requirements of the present invention. On the other hand, when the pore volume is too large, moisture or the like easily enters the silica particles, leading to deterioration of the fluorescent complex. The specific surface area is 50m.²/ G or more, preferably 200 m²/ G or more, particularly preferably 300 m²/ G. The upper limit is 800m²/ G or less. When the specific surface area is small, the pores are not sufficiently developed and the amount of insertion of the fluorescent complex is reduced. On the other hand, when the specific surface area is large, the pores are large and moisture is easily adsorbed, which causes deterioration of the fluorescent complex. . These pore volume and specific surface area are measured by the BET method by nitrogen gas adsorption / desorption.
[0014]
Further, in the case of silica particles, from the isothermal desorption curve measured by the nitrogen gas adsorption / desorption method, E.I. P. Barrett, L.M. G. Joyner, P.M. H. Haklenda, J .; Amer. Chem. Soc. , Vol. 73, 373 (1951), the pore distribution curve calculated by the BJH method, that is, the differential nitrogen gas adsorption amount (ΔV / Δ (logd)) with respect to the pore diameter d (nm); The mode diameter (Dmax) on the plot of (volume) is less than 20 nm, and the lower limit is not particularly limited, but is preferably 2 nm or more. This means that the mode diameter (Dmax) of the silica particles used in the present invention is in a range smaller than that of ordinary silica particles.
[0015]
In the silica particles suitably used in the present invention, the volume of pores in the range of ± 20% of the value of the mode diameter (Dmax) is usually 50% or more, preferably 60% or more of the total pore volume. It is preferable that The pore volume in the range of ± 20% of the value of the mode diameter (Dmax) is usually 90% or less of the total pore volume. This means that the silica particles are aligned with pores near the mode diameter (Dmax).
[0016]
In relation to such characteristics, the silica particles generally have a differential pore volume ΔV / Δ (logd) at the mode diameter (Dmax) calculated by the BJH method of generally 2.0 to 20.0 ml / g, particularly It is preferably 5.0 to 12.0 ml / g (in the above formula, d is the pore diameter (nm) and V is the nitrogen gas adsorption volume.
). When the differential pore volume ΔV / Δ (logd) is included in the above range, it can be said that the absolute amount of pores arranged in the vicinity of the mode diameter (Dmax) is extremely large.
[0017]
In addition to the characteristics of the pore structure described above, the silica particles suitably used in the present invention have a characteristic that they are amorphous, that is, no crystalline structure is observed in view of their three-dimensional structure. . This means that when the silica particles are analyzed by X-ray diffraction, substantially no crystalline peak is observed. In the present invention, the non-amorphous silica particles refer to those having at least one crystal structure peak at a position exceeding 6 angstroms (Å Units d-spacing) in the X-ray diffraction pattern. Amorphous silica particles are extremely excellent in water resistance compared to crystalline silica particles.
[0018]
In addition, regarding the structure of the silica particles preferably used in the present invention, a characteristic result can be obtained even by analysis by solid-state Si-NMR. That is, in the solid Si-NMR, the silica particles of the present invention have a molar ratio of “Q4 / Q3” indicating the molar ratio of Si (Q3) bonded with three —OSi and Si (Q4) bonded with four —OSi. The value is usually 1.3 or more, preferably 1.5 or more. Generally, it is said that the greater the value of “Q4 / Q3”, the higher the thermal stability. The value of “Q4 / Q3” is usually 10 or less.
[0019]
In the silica particles used in the present invention, the total content of metal impurities excluding silicon constituting the skeleton of the silica gel and excluding metal atoms constituting the inserted fluorescent complex is usually 500 ppm or less, preferably 100 ppm or less. More preferably, the purity is extremely high, such as 10 ppm or less, and most preferably 1 ppm or less. However, the small influence of impurities in this way exhibits excellent properties such as heat resistance and water resistance in silica particles. As a result, it is one of the major factors for obtaining a high-luminance luminescent material.
[0020]
Silicon alkoxide used as a raw material for silica particles includes trimethoxysilane, tetramethoxysilane, triethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, and other trialkyls having a lower alkyl group having 1 to 4 carbon atoms. Alternatively, tetraalkoxysilane or oligomer thereof may be mentioned, and tetramethoxysilane, tetraethoxysilane and oligomer thereof are preferable. Since the above silicon alkoxide can be easily purified by distillation, it is suitable as a raw material for high-purity silica particles. The total content of metal impurities in the silicon alkoxide is usually preferably 100 ppm or less, more preferably 10 ppm or less. The content of metal impurities can be measured by the same method as the method for measuring impurities in silica particles.
[0021]
The hydrolysis of the silicon alkoxide is usually performed using 2 to 20 mol, preferably 3 to 10 mol, particularly preferably 4 to 8 mol, of water with respect to 1 mol of the silicon alkoxide. Hydrolysis of the silicon alkoxide produces silica hydrogel and alcohol. This hydrolysis reaction is usually from room temperature to about 100 ° C., but it can also be performed at a higher temperature by maintaining the liquid phase under pressure. The reaction time depends on the composition of the reaction solution (type of silicon alkoxide and molar ratio with water) and the reaction temperature, and since the time until gelation varies, it is not generally specified. In addition, hydrolysis can be accelerated | stimulated by adding an acid, an alkali, salts, etc. to a reaction system as a catalyst.
[0022]
In the above silicon alkoxide hydrolysis reaction, the silicon alkoxide is hydrolyzed to produce a silicate. Subsequently, a condensation reaction of the silicate occurs, the viscosity of the reaction solution rises, and finally gelates to form a silica hydrogel. Become. The hydrogel of silica produced by hydrolysis is immediately subjected to hydrothermal treatment without substantially aging. As conditions for this hydrothermal treatment, the state of water may be either liquid or gas, and it may be diluted with a solvent or other gas, but preferably liquid water is used. 0.1 to 10 times by weight, preferably 0.5 to 5 times by weight, particularly preferably 1 to 3 times by weight water is added to the silica hydrogel to form a slurry, usually 40 to 250 ° C., preferably Is carried out at a temperature of 50 to 200 ° C. for usually 0.1 to 100 hours, preferably 1 to 10 hours. The water used for the hydrothermal treatment may contain lower alcohols, methanol, ethanol, propanol and the like.
[0023]
The amount of the fluorescent complex inserted into the porous inorganic particles is 9 wt% or more, preferably 10 wt% or more, and the upper limit is 100 wt% or less, preferably 75 wt% or less. When the insertion amount of the fluorescent complex is small, it is difficult to obtain sufficient luminance. Conversely, even if the amount is too large, the luminance approaches the saturation value as the insertion amount increases, so that luminance corresponding to the insertion amount cannot be obtained. Absent.
[0024]
As the fluorescent complex, a rare earth ion complex-based phosphor is preferably used, and as the rare earth element, elements such as Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb can be used. Eu is preferably used.
The rare earth ion complex-based phosphor is not particularly limited, but among the rare earth ion complexes, a europium complex is preferable as a red phosphor that emits light with high brightness when irradiated with near ultraviolet light, which is difficult with inorganic phosphors. . The rare earth ion complex is preferably a complex having a ligand of an anion of β-diketone having a substituent containing an aromatic ring or a carboxylate ion having a substituent containing an aromatic group.
[0025]
The complex having a β-diketone anion having a substituent containing an aromatic ring as a ligand is represented by any one of the following general formulas (1), (2) and (3), for example. Examples include europium complexes.
[0026]
[Chemical 1]
(R₅)₃Eu (1)
(R₅)₃Eu (R₆)₂            (2)
[(R₅)₄Eu]⁻R₇ ⁺            (3)
[0027]
(In the formulas (1), (2) and (3), R₅Is an anion of a β-diketone having a substituent containing an aromatic ring, and R₆Is an auxiliary ligand comprising a Lewis base and R₇ ⁺Is a quaternary ammonium ion. )
The β-diketone having a substituent containing an aromatic ring in the formulas (1), (2) and (3) preferably has at least one aromatic group, and the aromatic group may be substituted. An aromatic hydrocarbon compound or an aromatic heterocyclic compound that may have a group may be mentioned. Examples of the aromatic hydrocarbon compound include benzene, naphthalene, phenanthrene, and the like. Examples of the aromatic heterocyclic compound include heterocyclic compounds containing oxygen, nitrogen, and sulfur atoms such as furan, thiophene, pyrazoline, pyridine, carbazole, dibenzofuran, and dibenzothiophene.
[0028]
Examples of the substituent of these aromatic hydrocarbon compounds or aromatic heterocyclic compounds include alkyl groups such as methyl, ethyl, propyl, and butyl; fluoroalkyl groups such as trifluoromethyl and pentafluoromethyl; methoxy, Alkoxy groups such as ethoxy; aryloxy groups such as benzyl and phenethyl; hydroxyl groups; allyl groups; acyl groups such as acetyl and propionyl; acyloxy groups such as acetoxy, propionyloxy and benzoyloxy; alkoxycarbonyls such as methoxycarbonyl and ethoxycarbonyl Group; aryloxycarbonyl group such as phenoxycarbonyl; carboxyl group; carbamoyl group; amino group; substituted amino such as dimethylamino, diethylamino, methylbenzylamino, diphenylamino, acetylmethylamino Groups; methylthio, ethylthio, phenylthio, substituted thio group such as benzylthio; a mercapto group; ethylsulfonyl, substituted sulfonyl groups such as phenylsulfonyl; cyano group; fluoro, chloro, bromo, and the like halogen groups iodine and the like. These substituents may be bonded to each other to form a ring.
[0029]
Examples of the substituent other than the aromatic group constituting the β-diketone include the same substituents as those of the aromatic hydrocarbon compound or aromatic heterocyclic compound described above (however, the halogen group is excluded). Specific examples (1 to 19) of β-diketone having a substituent containing an aromatic ring are shown below. Note that the present embodiment is not limited to these.
[0030]
[Chemical formula 2]

[0031]
Specific examples (1 to 7) of the europium complex represented by the general formula (1) are shown below.
Note that the present embodiment is not limited to these.
[0032]
[Chemical Formula 3]

[0033]
Next, the europium complex represented by the general formula (2) will be described. Auxiliary ligand (R) consisting of a Lewis base in the general formula (2)₆) Is not particularly limited, but is usually selected from Lewis base compounds having a nitrogen atom or an oxygen atom capable of coordinating with the europium ion. Examples thereof include amines, amine oxides, phosphine oxides, sulfoxides and the like that may have a substituent.
The two Lewis base compounds used as auxiliary ligands may be different from each other, or two compounds may form one compound.
[0034]
Specifically, for example, amines include pyridine, pyrazine, quinoline, isoquinoline, phenanthridine, 2,2'-bipyridine, 1,10-phenanthroline, and the like. Examples of the amine oxide include N-oxides of the above amines such as pyridine-N-oxide and 2,2'-bipyridine-N, N'-dioxide. Examples of the phosphine oxide include triphenylphosphine oxide, trimethylphosphine oxide, and trioctylphosphine oxide.
Examples of the sulfoxide include diphenyl sulfoxide and dioctyl sulfoxide. Examples of the substituent that substitutes for these include the substituents described above.
Among these, an alkyl group, an aryl group, an alkoxyl group, an aralkyl group, an aryloxy group, a halogen group and the like are particularly preferable.
[0035]
Among these Lewis base compounds, when two atoms coordinated in the molecule, such as a nitrogen atom, such as bipyridine and phenanthroline, are present, two auxiliary ligands can be combined with one Lewis base compound. You may do the same work. In addition, as a substituent substituted by these Lewis base compounds, the substituent mentioned above is illustrated.
Among these, an alkyl group, an aryl group, an alkoxyl group, an aralkyl group, an aryloxy group, a halogen group and the like are particularly preferable.
[0036]
Lewis base compounds used as auxiliary ligands (R₆Specific examples (1 to 23) of) are exemplified below. Note that the Lewis base compound used in the present embodiment is not limited to these.
[0037]
[Formula 4]

[0038]
Specific examples (1 to 13) of the europium complex represented by the general formula (2) are shown below. Note that the present embodiment is not limited to these.
[0039]
[Chemical formula 5]

[0040]
Next, the europium complex represented by the general formula (3) will be described. Examples of ammonium ions in general formula (3) include quaternary ammonium salts derived from alkylamines, arylamines, and aralkyl ions. Examples of amine substituents include alkyl groups such as methyl, ethyl, propyl, butyl, hexyl and octyl; substituted alkyl groups such as hydroxyethyl and methoxyethyl; aryl groups such as phenyl and tolyl; arylalkyls such as benzyl and phenethyl groups Groups and the like.
[0041]
Specific examples (1-5) of the europium complex represented by the general formula (3) are shown below. Note that the present embodiment is not limited to these.
[0042]
[Chemical 6]

[0043]
Examples of the complex having a carboxylate ion having a substituent containing an aromatic group, which is another compound of the rare earth ion complex, include a europium complex represented by the following general formula (4). .
[0044]
[Chemical 7]
(R₈-(X)_n-COO)₃Eu (R₉)₂          (4)
(Wherein R₈Is a group containing at least one aromatic hydrocarbon ring or aromatic heterocyclic ring which may have a substituent, X is a divalent linking group, n is 0 or 1, R₉Is an auxiliary ligand comprising a Lewis base. )
The ligand represented by the general formula (4) includes at least one aromatic ring, 8 or more π electrons, and a carboxylate ion constituting a π electron conjugated system is used as the ligand. From the point of absorption wavelength range, it is preferable. The number of aromatic rings is not particularly limited as long as the triplet energy of the carboxylate ion base compound is higher than the europium ion excited state energy level. It is preferable to use a group heterocycle. When the number of aromatic rings is 4 or more, for example, a compound such as pyrene having 4 or more aromatic rings has low triplet energy excited by absorbing light from the first light emitter. The europium complex may not emit light.
[0045]
R in the general formula (4)₈Is preferably a monovalent group derived from a tricyclic or lower aromatic ring or a heteroaromatic ring which may have a substituent. Examples of the aromatic ring include aromatic monocyclic hydrocarbons or aromatic condensed polycyclic hydrocarbons such as benzene, naphthalene, indene, biphenylene, acenaphthene, fluorene, phenanthrene, tetralin, indane, and indene; benzoquinone, naphthoquinone, And compounds derived from aromatic hydrocarbons such as anthraquinone. Heteroaromatic rings include aromatic monocyclic heterocycles or aromatics such as furan, pyrrole, thiophene, oxazole, isoxazole, thiazole, imidazole, pyridine, benzofuran, benzothiophene, coumarin, benzopyran, carbazole, xanthene, quinoline, triazine. Group condensed polycyclic heterocycle and the like.
[0046]
R₈Substituents that may have include alkyl groups such as methyl, ethyl, propyl, and butyl; fluoroalkyl groups such as trifluoromethyl and pentafluoroethyl; cycloalkyl groups such as cyclohexyl group; ethynyl groups; phenylethynyl, pyridyl Arylethynyl groups such as ethynyl and thienylethynyl; alkoxy groups such as methoxy and ethoxy; aryl groups such as phenyl and naphthyl; aralkyl groups such as benzyl and phenethyl; aryloxy groups such as phenoxy, naphthoxy and biphenyloxy; hydroxyl groups; Groups; acyl groups such as acetyl, propionyl, benzoyl, toluoyl and biphenylcarbonyl; acyloxy groups such as acetoxy, propionyloxy and benzoyloxy; alcohols such as methoxycarbonyl and ethoxycarbonyl Sicarbonyl group; aryloxycarbonyl group such as phenoxycarbonyl; carboxyl group; carbamoyl group; amino group; substituted amino group such as dimethylamino, diethylamino, methylbenzylamino, diphenylamino, acetylmethylamino; methylthio, ethylthio, phenylthio, benzylthio Substituted thio groups such as: mercapto groups; substituted sulfonyl groups such as ethylsulfonyl and phenylsulfonyl groups; cyano groups; halogen groups such as fluoro, chloro, bromo and iodo. Among these, an alkyl group, an alkoxy group, an aryl group, a cycloalkyl group, a cycloalkyl group, an aryloxy group, an aralkyl group, an ethynyl group, and a halogen group are preferable. R₈Is not limited to these substituents. Moreover, these substituents may further have a substituent.
[0047]
Next, the carboxylate ion in General formula (4) is divided into the case where it does not have X which is a bivalent coupling group (n = 0), and the case where it has (n = 1). Furthermore, when it has X which is a bivalent coupling group (n = 1), X is divided into two types, when it has a carbonyl group and when it does not. Therefore, the carboxylate ion in the general formula (4) is further represented by the following general formula (5) having no carbonyl group and the general formula (6) having a carbonyl group. As the europium complex, any of complex structures having these carboxylate ions as ligands can be used.
[0048]
[Chemical 8]

[0049]
In general formula (5) and general formula (6), R₁₀Can be any divalent linking group, for example, an alkylene group, a divalent linking group derived from a ring-assembled hydrocarbon, an aliphatic ring, an aromatic ring, or a heterocyclic ring. Valent linking groups and the like. In general formula (6), m is 0 or 1. R₁₀Examples of the alkylene group include methylene and ethylene. Examples of the ring assembly hydrocarbon include biphenyl, terphenyl, binaphthyl, cyclohexylbenzene, and phenylnaphthalene. Examples of the aliphatic ring include cyclopentane, cyclohexane, cycloheptane, norbornane, bicyclohexyl and the like. Examples of the aromatic ring include the same compounds as the specific examples of the aromatic ring described above. Examples of the heterocyclic ring include aliphatic heterocyclic rings such as pyrazoline, piperazine, imidazolidine, and morpholine in addition to the aromatic heterocyclic ring described above. Other -SCH₂Thioalkylene such as -OCH;₂-Oxyalkylene such as-; vinylene (-C = C-) and the like. R₁₀Is not limited to these divalent substituents. These divalent substituents may further have a substituent.
[0050]
Specific examples of the carboxylic acid from which the carboxylic acid ion in general formula (4) is derived are illustrated below. In addition, the carboxylic acid used in this Embodiment is not limited to these. The following carboxylic acid (1-10) is mentioned as a compound in case n is 0 in General formula (4).
[0051]
[Chemical 9]

[0052]
Next, in general formula (4), n is 1 and X is R₁₀The following carboxylic acid (11-15) is mentioned as a compound of (Formula (5)).
[0053]
[Chemical Formula 10]

[0054]
Next, in the general formula (6), examples of the compound when m is 0 include the following carboxylic acids (16 and 17).
[0055]
Embedded image

[0056]
In the general formula (6), m is 1, and R₈Is a phenyl group, R₁₀Examples of the compound in the case where is a phenyl group include the following carboxylic acids (18 to 30).
[0057]
Embedded image

[0058]
In the general formula (6), m is 1, and R₈Is a phenyl group, R₁₀The following carboxylic acid (31-34) is mentioned as a compound in case that is a naphthyl group.
[0059]
Embedded image

[0060]
In the general formula (6), m is 1, and R₈Is a phenyl group, R₁₀The following carboxylic acid (35-37) is mentioned as a compound when is other group.
[0061]
Embedded image

[0062]
In the general formula (6), m is 1, and R₈Is a naphthyl group, R₁₀The following carboxylic acid (38-41) is mentioned as a compound when is an aromatic ring.
[0063]
Embedded image

[0064]
In the general formula (6), m is 1, and R₈Is a naphthyl group, R₁₀The following carboxylic acid (42-44) is mentioned as a compound when is other group.
[0065]
Embedded image

[0066]
In the general formula (6), m is 1, and R₈Is an acenaphthyl group, R₁₀Examples of the compound in the case of a phenyl group include the following carboxylic acids (45 to 48).
[0067]
Embedded image

[0068]
In the general formula (6), m is 1, and R₈Is a fluorenyl group, R₁₀The following carboxylic acid (49-55) is mentioned as a compound when is a phenyl group.
[0069]
Embedded image

[0070]
In the general formula (6), m is 1, and R₈Is a phenanthrenyl group, R₁₀Examples of the compound in the case of a phenyl group include the following carboxylic acids (56 to 59).
[0071]
Embedded image

[0072]
In the general formula (6), m is 1, and R₈Is a heterocyclic group, R₁₀Examples of the compound in which is a phenyl group include the following carboxylic acids (60 and 61).
[0073]
Embedded image

[0074]
The carboxylic acid from which the carboxylate ion as the ligand in the general formula (4) is derived can be synthesized by a known synthesis method. As for the synthesis method, for example, New Experimental Chemistry Course Volume 14 “Synthesis and Reaction of Organic Compounds (II)”, page 921 (1977), edited by The Chemical Society of Japan, or 4th edition Experimental Chemistry Course Volume 22 “Organic Synthesis” IV ", page 1 (1992) edited by the Chemical Society of Japan. Typical examples of the synthesis method include oxidation reaction of the corresponding primary alcohol or aldehyde, hydrolysis reaction of ester or nitrile, Friedel-Crafts reaction with acid anhydride, and the like.
[0075]
In particular, cyclic anhydrides of dicarboxylic acids such as phthalic anhydride, naphthalic anhydride, succinic anhydride, diphenic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 2,3-pyridazine dicarboxylic anhydride were used. In the Friedel-Crafts reaction, a carboxylic acid having a carbonyl group in the molecule can be synthesized. For example, according to the Friedel-Crafts reaction using an aromatic hydrocarbon or aromatic heterocycle and phthalic anhydride, a carboxylic acid having a carbonyl group bonded to the ortho position of the benzene ring is represented by the following reaction formula: Easy to synthesize. A carboxylic acid having a carbonyl group bonded to the ortho position of the benzene ring is preferable because a complex having higher luminance than that of the para-substituted product can be easily obtained. In the formula, Ar represents an aromatic hydrocarbon or an aromatic heterocyclic ring.
[0076]
Embedded image

[0077]
Auxiliary ligand (R) consisting of a Lewis base in the general formula (4)₉) As an auxiliary ligand (R) composed of a Lewis base in the general formula (2) described above.₆) And the same compounds.
In the present invention, the light-emitting substance is excited as a second light emitter by light of 350 to 415 nm from the first light emitter, and generates visible light. The luminescent material has good color rendering properties and emits visible light having a strong luminescence intensity when excited with light having a wavelength of 350 to 415 nm. In particular, the present inventors have discovered that 400 nm excitation light emitted from a GaN-based semiconductor as the first light emitter emits fluorescence having high color rendering properties and high luminance.
[0078]
In this invention, the said fluorescent substance can be used suitably for light-emitting devices, such as an illuminating device and an image display apparatus. The first light emitter that emits light generates light having a wavelength of 350 to 415 nm. Preferably, a light emitter that generates light having a peak wavelength in the wavelength range of 350 to 415 nm is used. Specific examples of the first light emitter include a light emitting diode (LED) or a laser diode (LD). A laser diode is more preferable because it consumes less power. Of these, GaN LEDs and LDs using GaN compound semiconductors are preferred. This is because GaN-based LEDs and LDs have significantly higher light emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely bright with very low power when combined with the phosphor. This is because light emission can be obtained. For example, for a current load of 20 mA, the GaN system usually has a light emission intensity 100 times or more that of the SiC system. In GaN LED and LD, Al_XGa_YN light emitting layer, GaN light emitting layer, or In_XGa_YWhat has N light emitting layer is preferable. Among GaN-based LEDs, In_XGa_YThose having an N light emitting layer are particularly preferable because the light emission intensity is very strong._XGa_YA multi-quantum well structure of an N layer and a GaN layer is particularly preferable because the emission intensity is very strong. In the above, the value of X + Y is usually a value in the range of 0.8 to 1.2. In the GaN-based LED, those in which the light emitting layer is doped with Zn or Si or those without a dopant are preferable for adjusting the light emission characteristics. A GaN-based LED has these light-emitting layer, p-layer, n-layer, electrode, and substrate as basic components, and the light-emitting layer is made of n-type and p-type Al._XGa_YN layer, GaN layer, or In_XGa_YThose having a heterostructure sandwiched between N layers and the like have high luminous efficiency, and those having a heterostructure having a quantum well structure further have high luminous efficiency, and are more preferable.
[0079]
In the present invention, it is particularly preferable to use a surface-emitting type illuminant, particularly a surface-emitting GaN-based laser diode, as the first illuminant because the luminous efficiency of the entire light-emitting device is increased. A surface-emitting type illuminant is an illuminant that emits strong light in the surface direction of a film. In a surface-emitting GaN-based laser diode, the crystal growth of a light-emitting layer or the like is controlled, and a reflective layer or the like is successfully performed. By devising, the light emission in the surface direction can be made stronger than the edge direction of the light emitting layer. When the surface emitting type is used, the light emission cross-sectional area per unit light emission amount can be increased compared to the type that emits light from the edge of the light emitting layer. As a result, the phosphor of the second light emitter is irradiated with the light. Since the irradiation area can be made very large with the same amount of light and the irradiation efficiency can be improved, stronger light emission can be obtained from the phosphor that is the second light emitter.
[0080]
When a surface-emitting type is used as the first light emitter, the second light emitter is preferably a film. As a result, the cross-sectional area of the light from the surface-emitting type light emitter is sufficiently large. Therefore, when the second light emitter is formed into a film in the direction of the cross section, the irradiation cross-section area of the phosphor from the first light emitter is irradiated. Becomes larger per unit amount of phosphor, so that the intensity of light emitted from the phosphor can be further increased.
[0081]
Further, when a surface-emitting type is used as the first light emitter and a film-like one is used as the second light emitter, the second light emitter directly in the form of a film on the light-emitting surface of the first light emitter. It is preferable to have a shape in which is contacted. Contact here means to create a state in which the first light emitter and the second light emitter are in perfect contact with each other without air or gas. As a result, it is possible to avoid a light amount loss in which light from the first light emitter is reflected by the film surface of the second light emitter and oozes out, so that the light emission efficiency of the entire apparatus can be improved.
[0082]
The light from the first illuminant and the light from the second illuminant are usually directed in all directions. However, when the phosphor powder of the second illuminant is dispersed in the resin, the light is out of the resin. A part of the light is reflected when exiting, so the direction of the light can be adjusted to some extent. Accordingly, since light can be guided to a certain degree in an efficient direction, it is preferable to use a phosphor in which the phosphor powder is dispersed in a resin as the second luminous body. Further, when the phosphor is dispersed in the resin, the total irradiation area of the light from the first light emitter to the second light emitter is increased, so that the light emission intensity from the second light emitter can be increased. It also has the advantage of being able to. Examples of resins that can be used in this case include epoxy resins, polyvinyl resins, polyethylene resins, polypropylene resins, polyester resins, and the like. From the viewpoint of good dispersibility of the phosphor powder, epoxy resins are preferable. It is. When the powder of the second luminous body is dispersed in the resin, the weight ratio of the powder of the second luminous body to the whole of the resin is usually 10 to 95%, preferably 20 to 90%, more preferably. Is 30-80%. If the phosphor is too much, the luminous efficiency may be reduced due to aggregation of the powder, and if it is too little, the luminous efficiency may be lowered due to light absorption or scattering by the resin.
[0083]
It is preferable that the light emitting substance which is the second light emitter used in the light emitting device to which the present invention is applied is shielded from light of substantially 350 nm or less with respect to the light from the first light emitter. (1) A method of providing an ultraviolet absorbing layer containing an ultraviolet absorbing material that substantially absorbs ultraviolet light of 350 nm or less between the luminescent material and the luminescent material, and blocking light of 350 nm or less; (2) 350 nm or less There is a method in which a semiconductor light emitter made of LED or LD that does not substantially emit light of wavelength is used as a light source.
[0084]
For ultraviolet light from external light, a method of blocking an ultraviolet light of external light by providing an ultraviolet absorbing layer between the light emitting substance and the external light can be mentioned. In this case, it is necessary to arrange the light emitting material so as not to shield light from the light emitting material. In addition, it is desirable that ultraviolet light from outside light be shielded from ultraviolet light having a wavelength of 400 nm or less in consideration of measures against light deterioration of organic compounds such as resins coexisting in addition to the fluorescent complex.
[0085]
In the light emitting device to which the present invention is applied, when an LED or LD is used as a light emitter, a film made of a resin composition in which a light emitting substance containing a fluorescent complex is mixed or dispersed in a resin on the upper side of the light emitter element The phosphor layer is formed, or the phosphor is mixed or dispersed in a sealing resin such as an epoxy resin covering the LED and LD. In the former case, ultraviolet rays from external light can be blocked by laminating an ultraviolet absorbing layer on the light emitting material layer or by containing an ultraviolet absorbing material in a sealing resin provided on the light emitting material layer. In the latter case, for example, the ultraviolet absorbing layer is formed so as to cover the outside of the sealing resin body provided with the light emitter and the light emitting substance. In either case, ultraviolet light from outside light in a wavelength region of 400 nm or less where the luminescent material or resin may be deteriorated is shielded, and extremely good light fastness can be obtained.
[0086]
Furthermore, in the case of a lamp-type light emitting device using a light transmissive material such as glass or resin glass, an ultraviolet absorber is mixed with the light transmissive material used for the lamp vessel, and an ultraviolet absorbing layer is provided on the outside or inside of the lamp vessel. By performing ultraviolet absorption treatment such as providing, it is possible to cut ultraviolet rays having a wavelength of 350 nm or less, preferably 400 nm or less. In the case of a lamp-type light emitting device, the light resistance can be dramatically improved by making the inside of the lamp a low oxygen concentration atmosphere by vacuum or inert gas replacement. The oxygen concentration is 1000 ppm or less, preferably 100 ppm or less, more preferably 20 ppm or less.
[0087]
The light-emitting device of the present invention includes the light-emitting substance as a wavelength conversion material and a light-emitting element that emits light of 350 to 415 nm, and the light-emitting substance absorbs light of 350 to 415 nm emitted from the light-emitting element. In addition, it is a light emitting device that has good color rendering properties and can generate high-intensity visible light regardless of the use environment, and a light source such as a backlight light source and a traffic light, and an image display device such as a color liquid crystal display. And suitable for light sources such as lighting devices such as surface emitting.
[0088]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
A method for analyzing silica particles, an amine treatment method, and a method for evaluating characteristics when a phosphor is used are described below.
1) Average pore size of silica particles
From the isothermal desorption curve measured by the nitrogen gas adsorption / desorption method, P. Barrett, L.M. G. Joyner, P.M. H. Haklenda, J .; Amer. Chem. Soc. , Vol. 73, 373 (1951).
2) Average particle diameter of silica particles
It measured using the particle size distribution analyzer LA-920 made from HORIBA.
[0089]
3) Pore volume and specific surface area of silica particles
The BET nitrogen adsorption isotherm was measured with AS-1 manufactured by Cantachrome, and the pore volume and specific surface area were determined. Specifically, the pore volume is relative pressure P / P₀= 0.98 is adopted, and the specific surface area is P / P₀= Calculated using the BET multipoint method from three points of nitrogen adsorption amounts of 0.1, 0.2, and 0.3. Further, the pore distribution curve and the differential pore volume at the mode diameter (Dmax) were determined by the BJH method. The interval between each point of the relative pressure to be measured was 0.025.
[0090]
4) Content of metal impurities in silica particles
After adding hydrofluoric acid to 2.5 g of silica particles and heating to dryness, water was added to make 50 ml. ICP emission analysis was performed using this aqueous solution. Sodium and potassium were analyzed by flame flame light method.
5) Powder X-ray diffraction
Using a RAD-RB apparatus manufactured by Rigaku Corporation, measurement was performed using CuKα as a radiation source. The divergence slit was ½ deg, the scattering slit was ½ deg, and the light receiving slit was 0.15 mm.
[0091]
6) Amine treatment
A 50 ml eggplant flask was charged with 0.15 g of aminopropyltriethoxysilane and 10 g of ethanol, stirred at room temperature for 15 minutes, and then added with 3 g of mesoporous silica. After stirring at room temperature for 30 hours, the silica particles were filtered off and washed thoroughly with ethanol. The obtained silica particles were heated at 50 ° C. for 6 hours and then allowed to stand at room temperature for 3 days for curing. Thereafter, drying under reduced pressure was performed to obtain silica particles having aminopropyl groups introduced on the surface. -NH₂Coloration (confirmation of the presence of amino groups) was confirmed with ninhydrin as a color reagent.
[0092]
7) Fluorescent complex content
It calculated from the weight increase after fluorescent complex insertion.
8) Luminance measurement
Hitachi's fluorescence spectrometer F-4500 was used. Approximately 200 mg of powder is packed in a powder holder (Hitachi Instrument Service Co., Ltd. powder cell (fluorescence)), the excitation wavelength is 400 nm, the fluorescence intensity is the peak intensity value at 610 nm of the emission peak, and the inorganic red fluorescence Substance Y₂O₂S: The value of Eu is shown as 100.
[0093]
Example 1
As silica particles, mesoporous silica manufactured by Mitsubishi Chemical (average pore size: 7 nm, average particle size: 3 μm, specific surface area: 685 m)²/ G, pore volume; 1.0 cc / g). The impurity concentration of the silica particles was 0.2 ppm sodium, 0.1 ppm potassium, 0.2 ppm calcium, and magnesium, aluminum, titanium, and zirconium were not detected. Further, when powder X-ray diffraction measurement was performed, no crystalline peak appeared in the powder X-ray diffraction pattern, and no peak on the low angle side (2θ ≦ 5 deg) due to the periodic structure was observed. . This mesoporous silica was amine-treated as described above. Eu complex represented by the following structural formula (Eu (TTA)₃Phen complex) 0.2 g was dissolved in 40 cc of THF, and 1.0 g of amine-treated silica particles were mixed and stirred overnight. The solvent was stripped by heating to 40 ° C., followed by vacuum degassing at room temperature for 5 hr to obtain a luminescent material.
[0094]
The insertion amount of the Eu complex is 16.5 wt%, and the emission luminance upon excitation at 400 nm by fluorescence spectroscopy is an inorganic red fluorescent substance Y₂O₂S: The value of Eu was set to 100, which was 900.
[0095]
Embedded image

[0096]
(Example 2)
Eu (TTA)₃A luminescent material was obtained in the same manner as in Example 1 except that the amount of the Phen complex was 0.4 g. The insertion amount of the Eu complex is 28.5 wt%, and the emission luminance upon excitation at 400 nm by fluorescence spectroscopy is an inorganic red fluorescent substance Y₂O₂The value of S: Eu was 1100, taken as 100.
(Example 3)
Eu (TTA)₃A luminescent material was obtained in the same manner as in Example 1 except that the amount of the Phen complex was 1.0 g. The insertion amount of the Eu complex is 50.0 wt%, and the emission luminance upon excitation at 400 nm by fluorescence spectroscopy is an inorganic red fluorescent substance Y₂O₂The value of S: Eu was 100, which was 2100.
Example 4
Eu (TTA)₃Eu (DBM) represented by the following structural formula instead of the Phen complex₃A luminescent material was obtained in the same manner as in Example 1 except that 0.1 g of Phen complex was used.
[0097]
The insertion amount of the Eu complex is 10.0 wt%, and the emission luminance upon excitation at 400 nm by fluorescence spectroscopy is an inorganic red fluorescent substance Y₂O₂S: The value of Eu was set to 100 and was 1000.
[0098]
Embedded image

[0099]
(Comparative Example 1)
As silica particles, mesoporous silica manufactured by Mitsubishi Chemical (average pore size: 4 nm, average particle size: 300 μm, specific surface area: 850 m)²/ G, pore volume; 0.88 cc / g). The impurity concentration of the silica particles was 0.2 ppm sodium, 0.1 ppm potassium, 0.2 ppm calcium, and magnesium, aluminum, titanium, and zirconium were not detected. Further, when powder X-ray diffraction measurement was performed, no crystalline peak appeared in the powder X-ray diffraction pattern, and no peak on the low angle side (2θ ≦ 5 deg) due to the periodic structure was observed. . This mesoporous silica was amine-treated as described above. Eu (DBM)₃Phen complex (0.1 g) was dissolved in 40 cc of THF, and 1.0 g of the amine-treated silica particles were mixed and stirred overnight. The solvent was evaporated by heating to 40 ° C., and vacuum degassing was further performed at room temperature for 5 hours to obtain the desired product. The insertion amount of the Eu complex is 10 wt%, and the emission luminance upon excitation at 400 nm by fluorescence spectroscopy is an inorganic red fluorescent substance Y₂O₂S: The value of Eu was set to 100, which was 700.
[0100]
【The invention's effect】
According to the present invention, it is possible to provide a light-emitting substance having high color rendering properties and high emission intensity, and a light-emitting device, a lighting device, and an image display device using the same.

Claims (12)

A luminescent substance comprising a fluorescent complex in porous inorganic particles having an average pore size of 5 to 500 nm. The light-emitting substance according to claim 1, comprising 9 wt% or more of a fluorescent complex. The luminescent substance according to claim 1 or 2, wherein the fluorescent complex is bonded to porous inorganic particles. The luminescent substance according to any one of claims 1 to 3, wherein the fluorescent complex is a rare earth ion complex-based phosphor. The luminescent material according to claim 1, wherein the porous inorganic particles are silica particles. 6. The luminescent material according to claim 5, wherein the silica particles have an average particle diameter in the range of 1 to 300 [mu] m and a specific surface area of 50 to 800 m < ² > / g. The luminescent material according to claim 5 or 6, wherein the pore volume of the silica particles is 0.6 to 1.6 ml / g and is amorphous. 8. The luminescent material according to claim 1, wherein the content of metal impurities other than the metal constituting the fluorescent complex is 500 ppm or less. The fluorescent complex is a complex having a ligand an anion derived from a β-diketone having a substituent containing an aromatic ring or a carboxylic acid having a substituent containing an aromatic ring. The luminescent material according to any one of 1 to 8. In a light-emitting device including a first light-emitting body that generates light of 350 to 415 nm and a second light-emitting body that generates visible light by irradiation of light from the first light-emitting body, A light-emitting device using the light-emitting substance according to claim 1. A lighting device comprising the light emitting device according to claim 10. An image display device comprising the light emitting device according to claim 10.