JP2004018768A

JP2004018768A - Method for producing fluorescent substance and apparatus for forming fluorescent substance precursor

Info

Publication number: JP2004018768A
Application number: JP2002178380A
Authority: JP
Inventors: Hideki Hoshino; 星野　秀樹; Satoshi Ito; 伊藤　聡; Naoko Furusawa; 古澤　直子; Takayuki Suzuki; 鈴木　隆行; Hisahiro Okada; 岡田　尚大
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2002-06-19
Filing date: 2002-06-19
Publication date: 2004-01-22

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a fluorescent substance having small particle diameters, a narrow particle diameter distribution and excellent emission intensity in the method for producing the fluorescent substance, in which a fluorescent substance precursor formed by using a liquid-phase method is fired. <P>SOLUTION: In the method for producing the fluorescent substance, in which the fluorescent substance precursor is formed in a liquid phase and the fluorescent substance precursor is fired, the method for producing the fluorescent substance comprises forming the fluorescent substance precursor while controlling pH, temperature and ion concentration of at least one kind of an element of constituent elements of the fluorescent substance precursor for at least a part of time from the start to the end of the formation of the fluorescent substance precursor. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は液相法を用いて生成された蛍光体前駆体及び該蛍光体前駆体を焼成して製造された蛍光体、さらには該蛍光体前駆体生成装置に関する。さらに、本発明は、プラズマディスプレイパネルなどの各種のフラットパネルディスプレイ、陰極線管、蛍光ランプ、放射線増感紙、インクジェット用インク、電子写真トナー、ハロゲン化銀写真材料に好適に用いることができる蛍光体に関する。
【０００２】
【従来の技術】
近年、情報化社会の進展の中でプラズマディスプレイパネルなどの各種のフラットパネルディスプレイやカラーブラウン管などのカラー陰極線管は、ハイビジョン用ブラウン管や高精細ディスプレイ管に象徴されるように大画面化、高コントラスト化が進むとともに、高精細化された画面を形成し得るように、より細かい画素をフェースプレート上に形成することが必要になっている。このため、蛍光体は発光輝度向上やフェースプレート面との付着力の向上など様々な特性の向上が求められている。
【０００３】
これまでのフラットパネルディスプレイ用蛍光体はカラー陰極線管用に開発された粒径２〜７μｍ程度の粒子が用いられており、励起波長も各フラットパネルディスプレイ用に最適化されたものの開発が進んでいないため、様々な特性の向上が求められている。特に、今後のディスプレイの高精細化に伴って小粒径且つ単分散で高い輝度を持った蛍光体が求められている。
【０００４】
一般的な蛍光体の製造方法として、蛍光体母体を構成する元素を含む化合物と賦活剤元素を含む化合物とを所定量混合した後に焼成して固体間反応を行う固相法と、蛍光体母体を構成する元素を含む溶液と賦活剤元素を含む溶液を共に混合して得られた蛍光体前駆体沈殿を固液分離してから焼成を行う液相法がある。
【０００５】
蛍光体の発光効率と収率を高めるためには、蛍光体組成をできるだけ化学量論的な組成に近づける必要があるが、固相法では純粋に化学量論的な組成を有する蛍光体を製造することは難しい。固相法は固体間反応であるために、反応しない余剰の不純物や反応によって生ずる副塩等が残留することが往々にして起こり、化学量論的に高純度な蛍光体を得にくい。
【０００６】
また、固相法によって得られる蛍光体は、比較的広い粒度分布を有し、特に多量の融剤を用いて焼成するときには、正規分布に近い広い粒度分布を有する蛍光体が得られる。そして、そういった蛍光体を用いて蛍光膜を形成するときには、輝度が高く、緻密な蛍光膜を得るためには、微細粒子や粗大粒子が多量に存在するのは好ましくない。これらの微細粒子や粗大粒子は必要に応じて分級操作により除去されるが、分級操作は作業性が悪く、収率を低下させ、特に、粗大粒子の形成は所望粒径の粒子の収率に大きく影響し、また、必ずしも確実に除去することができない。したがって、高精細陰極線管用蛍光膜の形成には、不要な微細粒子や粗大粒子、特に粗大粒子を焼成時に生成させないことが重要となる。
【０００７】
また、固相法によって得られる蛍光体は、粒径が小さくなるほど、発光効率、発光輝度が低下するため、１μｍ以下で十分な発光効率、発光輝度を持った蛍光体はほとんど供給されてないのが実情である。粒径１μｍ以下の蛍光体に関する製造方法もいくつか開示されているが、特開平８−８１６７８号等のように分級操作により１μｍ以下の粒子を得ており、分級操作による蛍光体輝度の低下と収率の低下という問題が生じる。
【０００８】
また、蛍光体製造の各工程において、凝集は粒子の粒径を増大させてしまい、蛍光体の微粒化に対して大きな妨げとなっていたが、これを防止する観点での発明は少なく、特開平６−３０６３５８号等に焼結防止剤の記述が存在するのみであり、その効果については十分とはいえない。
【０００９】
一方、液相法により蛍光体を製造する場合は、先ず、蛍光体前駆体である沈殿物を生成させた後、この蛍光体前駆体を焼成して蛍光体とする。液相法では、蛍光体を構成する元素イオンにより反応が生じるため、化学量論的に高純度な蛍光体が得やすいものの蛍光体の粒径や粒子形状、粒子径分布、発光特性などの諸特性は蛍光体前駆体の性状に大きく左右される。そのため、所望の蛍光体を得るには、蛍光体前駆体の生成時における粒子形状や粒子径分布の制御、不純物排除等に配慮することが必要である。
【００１０】
それ故、液相法による蛍光体の製造に関する改良法が数多く提案されている。例えば特開２００１−１７２６２７には蛍光ランプ用の希土類燐酸塩蛍光体の製造方法について、希土類元素のイオン及び燐酸イオンが共存する溶液をｐＨ１．０から２．０に制御された水溶液中に添加して希土類燐酸塩蛍光体前駆体を生成する旨が開示されている。また、特開平９−７１４１５号には希土類酸化物の製造方法について、希土類イオンと蓚酸イオンとの反応を−５℃以上２０℃以下に保った状態で反応させて球状希土類酸化物を生成する旨が開示されている。しかしながら、これらの方法では、固相法で得られる蛍光体と比べると高純度組成が得られる、球状粒子が得られる等のメリットがあるものの、小粒径と高い輝度を両立する蛍光体を得るにはまだ不十分であった。
【００１１】
【発明が解決しようとする課題】
本発明は、液相法を用いて生成される蛍光体前駆体を焼成することによって得られる蛍光体の製造方法において、粒子径が小さく、且つ粒子径分布が狭く、さらには発光強度が良好な蛍光体の製造方法を提供するものである。
【００１２】
【課題を解決するための手段】
本発明者等は、上記目的を達成するために液相法による蛍光体の製造方法について鋭意検討した結果、この蛍光体前駆体の生成条件をコントロールすることによって、粒子径が小さく、且つ粒子径分布が狭い発光強度の良好な蛍光体が製造できることを見出し、本発明を完成させるに至った。
【００１３】
本発明の構成は次のとおりである。
（１）　液相中で蛍光体前駆体を生成させた後、該蛍光体前駆体を焼成することにより蛍光体を得る蛍光体の製造方法において、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部をｐＨ制御しながら蛍光体前駆体を生成させることを特徴とする蛍光体の製造方法。
【００１４】
（２）　前記ｐＨ制御をｐＨ７からｐＨ１４の範囲で行うことを特徴とする（１）に記載の蛍光体の製造方法。
【００１５】
（３）　前記ｐＨ制御を２回以上行うことを特徴とする（１）または（２）に記載の蛍光体の製造方法。
【００１６】
（４）　液相中で蛍光体前駆体を生成させた後、該蛍光体前駆体を焼成することにより蛍光体を得る蛍光体の製造方法において、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部を温度制御しながら蛍光体前駆体を生成させることを特徴とする蛍光体の製造方法。
【００１７】
（５）　前記温度制御を３０℃から７０℃の範囲で行うことを特徴とする（４）に記載の蛍光体の製造方法。
【００１８】
（６）　前記温度制御を２回以上行うことを特徴とする（４）または（５）に記載の蛍光体の製造方法。
【００１９】
（７）　液相中で蛍光体前駆体を生成させた後、該蛍光体前駆体を焼成することにより蛍光体を得る蛍光体の製造方法において、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部を蛍光体前駆体の構成元素の少なくとも一種類の元素のイオン濃度を制御しながら該蛍光体前駆体を生成させることを特徴とする蛍光体の製造方法。
【００２０】
（８）　前記イオン濃度制御を２回以上行うことを特徴とする（７）に記載の蛍光体の製造方法。
【００２１】
（９）　前記蛍光体前駆体をバインダー存在下で生成させることを特徴とする（１）乃至（８）のいずれか１項に記載の蛍光体の製造方法。
【００２２】
（１０）　蛍光体前駆体を液相法により生成する蛍光体前駆体生成装置であって、該蛍光体前駆体を生成する反応容器中にｐＨセンサーが具備されていることを特徴とする蛍光体前駆体生成装置。
【００２３】
（１１）　蛍光体前駆体を液相法により生成する蛍光体前駆体生成装置であって、該蛍光体前駆体を生成する反応容器中に温度センサーが具備されていることを特徴とする蛍光体前駆体生成装置。
【００２４】
（１２）　蛍光体前駆体を液相法により生成する蛍光体前駆体生成装置であって、該蛍光体前駆体を生成する反応容器中にセンサーが少なくとも２種類以上具備されていることを特徴とする蛍光体前駆体生成装置。
【００２５】
（１３）　前記センサーが、温度センサー、ｐＨセンサー、金属イオン濃度センサーから選ばれる少なくとも２種類であることを特徴とする（１２）に記載の蛍光体前駆体生成装置。
【００２６】
【発明の実施の形態】
以下、本発明について詳細に説明する。
【００２７】
蛍光体前駆体とは、蛍光体の中間生成物であり、この蛍光体前駆体を所定の温度で焼成することにより蛍光体が得られる。
【００２８】
本発明に用いられる蛍光体の製造方法について説明する。
本発明者等は、蛍光体前駆体の生成条件、特に蛍光体前駆体の生成開始から終了までの時間におけるｐＨ、温度、蛍光体前駆体構成元素のイオン濃度、バインダー等の諸条件をコントロールすることによって、粒子径が小さく且つ粒子径分布が狭い発光強度の優れた蛍光体を製造出来ることを見出した。本発明の蛍光体の製造方法としては、蛍光体母体を構成する元素を含む溶液と賦活剤元素を含む溶液を共に混合して溶液中で蛍光体前駆体の沈殿を生成させ、この蛍光体前駆体を固液分離してから焼成する液相法が好ましく用いられる。
【００２９】
本発明においては、蛍光体前駆体の沈殿方法に特に限定はなく、反応晶析法や共沈法、Ｓｏｌ−Ｇｅｌ法等のいずれの方法によっても好ましく生成することが出来る。また、蛍光体の種類や所望の特性を得るために、原料溶液等の添加速度や添加位置、撹拌条件などは適宜調整することが好ましい。
【００３０】
図１に本発明における蛍光体前駆体の生成装置の概念図の一例を示すが、本発明はこの一例に限定されず、あらゆる態様が好ましく用いられる。図１において、容器１は最初に原料溶液［Ａ］を含有している。撹拌機構２は、回転可能な軸に翼が付設されたものとして図示されているが、この機構を任意の常用の形状とすることが可能である。撹拌機構２を運転しながら、注加ノズル３を通して蛍光体原料溶液［Ｂ］を容器１に、そしてこれと同時に注加ノズル４を通して蛍光体原料溶液［Ｃ］を容器１にそれぞれ注加する。このとき、センサー６により反応に伴って変化する容器１内の特性値を測定し、所望の特性値になるように調整液添加装置等（図示せず）に必要な添加量をフィードバックして注加ノズル５から調整液を容器１に注加することでリアルタイムに特性値を制御する。特性値は原料溶液の添加時間中は変更しなくてもよいし、必要に応じて適宜変更してもよい。原料溶液の添加終了後、一定時間熟成処理を施して蛍光体前駆体の生成が終了する。熟成時においては、ｐＨ、温度、イオン濃度等の特性値は原料溶液添加時と同じでもよく、また、必要に応じて適宜変更してもよい。
【００３１】
本発明でいう原料溶液とは、蛍光体の構成元素イオンまたは溶媒またはバインダーのうちの少なくとも一種類が含有されているものをいう。
【００３２】
本発明では、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部をｐＨ制御しながら蛍光体前駆体を生成させることが好ましく、さらにはｐＨ値をｐＨ７からｐＨ１４の範囲で制御しながら蛍光体前駆体を生成することが好ましく、ｐＨ制御を少なくとも２回以上行って蛍光体前駆体を生成することが最も好ましい態様である。
【００３３】
本発明では、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部を温度制御しながら蛍光体前駆体を生成することが好ましく、さらには温度を３０℃から７０℃の範囲で制御しながら蛍光体前駆体を生成することが好ましく、温度制御を少なくとも２回以上行って蛍光体前駆体を生成することが最も好ましい態様である。
【００３４】
本発明では、蛍光体前駆体の生成開始から終了までの時間の少なくとも一部を蛍光体の構成元素の少なくとも一種類のイオン濃度を制御しながら蛍光体前駆体を生成することが好ましく、さらにはイオン濃度を１×１０^−６ｍｏｌ／ｌから１×１０^２ｍｏｌ／ｌの範囲で制御しながら蛍光体前駆体を生成することが好ましく、イオン濃度制御を少なくとも２回以上行って蛍光体前駆体を生成することが最も好ましい態様である。
【００３５】
本発明は、注加ノズル数は３系統に限定されるものではなく、製造すべき蛍光体の種類や特性に応じて適宜増減することができる。本発明は、センサーに用いられるものとしてｐＨセンサーを用いることが好ましい。また、別の態様では、本発明は、センサーに用いられるものとして温度センサーを用いることが好ましい。さらに別の態様では、本発明は、センサーに用いられるものとして蛍光体の構成元素の少なくとも一種類のイオン濃度を測定するイオン濃度センサーを用いることが好ましい。本発明の好ましい態様では、センサーは１種類に限定されるものではなく、少なくとも２種類以上使用する。蛍光体の種類や特性に応じて、ｐＨ、温度、イオン濃度、を適宜組み合わせて使用することができる。最も好ましくは全てのセンサーを用いて蛍光体前駆体を生成することである。
【００３６】
また、予め別の容器で生成した結晶核を容器１に注加してもよく、さらには別の混合機で連続的に反応を生じさせた結晶核を連続的に容器１に供給する態様であってもよい。
【００３７】
本発明は、バインダーの存在下で蛍光体前駆体を生成することが好ましい。本発明におけるバインダーは、粒子同士の凝集を防ぐために機能しており、特開２００１−３２９２６２に開示されている晶癖制御に用いられている有機ポリマーとは明らかに機能が異なる。
【００３８】
本発明におけるバインダーとしては、天然、合成を問わず公知の高分子化合物を用いることができる。その際、バインダーの平均分子量は、１０，０００以上が好ましく、１０，０００以上３００，０００以下がより好ましく、１０，０００以上３０，０００以下が特に好ましい。また、本発明におけるバインダーは、タンパク質が好ましく、ゼラチンが特に好ましい。また、単一の組成である必要はなく、各種バインダーを混合してもよい。
【００３９】
本発明においては、蛍光体前駆体の固液分離方法に特に限定はなく、遠心分離、吸引濾過法等が好ましく用いられる。また、蛍光体前駆体溶液を乾燥機または噴霧熱分解炉のような焼成炉で直接処理してもよい。また、本発明においては、蛍光体前駆体の乾燥方法に特に限定はなく、真空乾燥、気流乾燥、流動層乾燥、噴霧乾燥等あらゆる方法が用いられる。
【００４０】
さらに、本発明において、蛍光体前駆体の焼成温度、焼成時間に特に限定はなく、蛍光体の種類に応じて適宜選択することができる。焼成時のガス雰囲気は酸化性雰囲気、還元性雰囲気、または不活性雰囲気のいずれでもよく、目的に応じて適宜選択できる。また、焼成装置としては、特に限定はなく、公知の焼成装置を使用することができる。例えば、箱型炉や坩堝炉、ロータリーキルン、噴霧熱分解炉等が好ましく用いられる。
【００４１】
本発明においては、燒結防止剤を添加しても添加しなくともよい。添加する場合は蛍光体前駆体生成時にスラリーとして添加してもよく、また、粉状のものを乾燥済蛍光体前駆体と共に混合して焼成する方法でも好ましく用いられる。さらに燒結防止剤に特に限定はなく、蛍光体の種類、焼成条件によって適宜選択される。例えば、蛍光体の焼成温度域によって８００℃以下での焼成にはＴｉＯ_２等の金属酸化物が、１，０００℃以下での焼成にはＳｉＯ_２が、１，７００℃以下での焼成にはＡｌ_２Ｏ_３が好ましく使用される。本発明においては、焼成後の蛍光体を洗浄することが望ましいが、必ずしも洗浄する必要はない。
【００４２】
本発明に係る蛍光体は、平均粒径が１．０μｍ以下であることが好ましく、０．８μｍ以下であることがより好ましく、０．５μｍ以下であることがさらに好ましく、０．０１μｍ以上０．３μｍ以下であることが最も好ましい。ここで示す平均粒径とは、粒子が立方体或いは八面体のいわゆる正常晶である場合には、粒子の稜の長さをいう。また、正常晶でない場合、例えば球状、棒状、或いは平板状の粒子の場合には、粒子の体積と同等な球を考えたときの直径を示す。
【００４３】
本発明において、蛍光体粒子の形状に特に限定はないが、立方体形状が好ましく、さらには八面体形状が好ましく、球形状がより好ましい態様である。
【００４４】
本発明の蛍光体は、粒径分布の変動係数が１００％以下であることが好ましく、５０％以下であることがさらに好ましく、３０％以下であることが最も好ましい。ここで粒子サイズの変動係数とは、下式によって定義される値である。
【００４５】
（粒子サイズの標準偏差／粒子サイズの平均値）×１００＝粒子分布の広さ（変動係数）［％］
本発明において、蛍光体は、必要に応じて表面改質剤や界面活性剤、微粒子シリカゲル、エアロジル、アルミナ等のマット化剤等により表面改質や分散性の向上を図ってもよい。
【００４６】
本発明に係る無機蛍光体粒子の組成は例えば、特開昭５０−６４１０号、同６１−６５２２６号、同６４−２２９８７号、同６４−６０６７１号、特開平１−１６８９１１号等に記載されており、特に制限はないが、結晶母体であるＹ_２Ｏ_２Ｓ、Ｚｎ_２ＳｉＯ_４、Ｃａ_５（ＰＯ_４）_３Ｃｌ等に代表される金属酸化物及びＺｎＳ、ＳｒＳ、ＣａＳ等に代表される硫化物に、Ｃｅ、Ｐｒ、Ｎｄ、Ｐｍ、Ｓｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ、Ｔｍ、Ｙｂ等の希土類金属のイオンやＡｇ、Ａｌ、Ｍｎ、Ｓｂ等の金属のイオンを賦活剤または共賦活剤として組み合わせたものが好ましい。
【００４７】
結晶母体の好ましい例としては、例えば、ＺｎＳ、Ｙ_２Ｏ_２Ｓ、Ｙ_３Ａｌ_５Ｏ_１２、Ｙ_２ＳｉＯ_５、Ｚｎ_２ＳｉＯ_４、Ｙ_２Ｏ_３、ＢａＭｇＡｌ_１０Ｏ_１７、ＢａＡｌ_１２Ｏ_１９、（Ｂａ，Ｓｒ，Ｍｇ）Ｏ・ＢａＡｌ_２Ｏ_３、（Ｙ，Ｇｄ）ＢＯ_３、ＹＯ_３、（Ｚｎ，Ｃｄ）Ｓ、ＳｒＧａ_２Ｓ_４、ＳｒＳ、ＧａＳ、ＳｎＯ_２、Ｃａ_１０（ＰＯ_４）_６（Ｆ，Ｃｌ）_２、（Ｂａ，Ｓｒ）（Ｍｇ、Ｍｎ）Ａｌ_１０Ｏ_１７、（Ｓｒ，Ｃａ，Ｂａ，Ｍｇ）_１０（ＰＯ_４）_６Ｃｌ_２、（Ｌａ，Ｃｅ）ＰＯ_４、ＣｅＭｇＡｌ_１１Ｏ_１９、ＧｄＭｇＢ_５Ｏ_１０、Ｓｒ_２Ｐ_２Ｏ_７、Ｓｒ_４Ａｌ_１４Ｏ_２５等が挙げられる。
【００４８】
以上の結晶母体及び賦活剤または共賦活剤は、同族の元素と一部置き換えたものでも構わないし、とくに元素組成に制限はない。
【００４９】
以下に無機蛍光体粒子の化合物例を示すが、本発明はこれらの化合物に限定されるものではない。
【００５０】
［青色発光無機蛍光化合物］
（ＢＬ−１）　Ｓｒ_２Ｐ_２Ｏ_７：Ｓｎ^４＋
（ＢＬ−２）　Ｓｒ_４Ａｌ_１４Ｏ_２５：Ｅｕ^２＋
（ＢＬ−３）　ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋
（ＢＬ−４）　ＳｒＧａ_２Ｓ_４：Ｃｅ^３＋
（ＢＬ−５）　ＣａＧａ_２Ｓ_４：Ｃｅ^３＋
（ＢＬ−６）　（Ｂａ，Ｓｒ）（Ｍｇ，Ｍｎ）Ａｌ_１０Ｏ_１７：Ｅｕ^２＋
（ＢＬ−７）　（Ｓｒ，Ｃａ，Ｂａ，Ｍｇ）_１０（ＰＯ_４）_６Ｃｌ_２：Ｅｕ^２＋
（ＢＬ−８）　ＺｎＳ：Ａｇ
（ＢＬ−９）　ＣａＷＯ_４
（ＢＬ−１０）　Ｙ_２ＳｉＯ_５：Ｃｅ^３＋
（ＢＬ−１１）　ＺｎＳ：Ａｇ，Ｇａ，Ｃｌ
（ＢＬ−１２）　Ｃａ_２Ｂ_５Ｏ_９Ｃｌ：Ｅｕ^２＋
（ＢＬ−１３）　ＢａＭｇＡｌ_１４Ｏ_２３：Ｅｕ^２＋
（ＢＬ−１４）　ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋，Ｔｂ^３＋，Ｓｍ^２＋
（ＢＬ−１５）　ＢａＭｇＡｌ_１４Ｏ_２３：Ｓｍ^２＋
（ＢＬ−１６）　Ｂａ_２Ｍｇ_２Ａｌ_１２Ｏ_２２：Ｅｕ^２＋
（ＢＬ−１７）　Ｂａ_２Ｍｇ_４Ａｌ_８Ｏ_１８：Ｅｕ^２＋
（ＢＬ−１８）　Ｂａ_３Ｍｇ_５Ａｌ_１８Ｏ_３５：Ｅｕ^２＋
（ＢＬ−１９）　（Ｂａ，Ｓｒ，Ｃａ）（Ｍｇ，Ｚｎ，Ｍｎ）Ａｌ_１０Ｏ_１７：Ｅｕ^２＋
［緑色発光無機蛍光体粒子］
（ＧＬ−１）　（Ｂａ，Ｍｇ）Ａｌ_１６Ｏ_２７：Ｅｕ^２＋，Ｍｎ^２＋
（ＧＬ−２）　Ｓｒ_４Ａｌ_１４Ｏ_２５：Ｅｕ^２＋
（ＧＬ−３）　（Ｓｒ，Ｂａ）Ａｌ_２Ｓｉ_２Ｏ_８：Ｅｕ^２＋
（ＧＬ−４）　（Ｂａ，Ｍｇ）_２ＳｉＯ_４：Ｅｕ^２＋
（ＧＬ−５）　Ｙ_２ＳｉＯ_５：Ｃｅ^３＋，Ｔｂ^３＋
（ＧＬ−６）　Ｓｒ_２Ｐ_２Ｏ_７−Ｓｒ_２Ｂ_２Ｏ_５：Ｅｕ^２＋
（ＧＬ−７）　（Ｂａ，Ｃａ，Ｍｇ）_５（ＰＯ_４）_３Ｃｌ：Ｅｕ^２＋
（ＧＬ−８）　Ｓｒ_２Ｓｉ_３Ｏ_８−_２ＳｒＣｌ_２：Ｅｕ^２＋
（ＧＬ−９）　Ｚｒ_２ＳｉＯ_４，ＭｇＡｌ_１１Ｏ_１９：Ｃｅ^３＋，Ｔｂ^３＋
（ＧＬ−１０）　Ｂａ_２ＳｉＯ_４：Ｅｕ^２＋
（ＧＬ−１１）　ＺｎＳ：Ｃｕ，Ａｌ
（ＧＬ−１２）　（Ｚｎ，Ｃｄ）Ｓ：Ｃｕ，Ａｌ
（ＧＬ−１３）　ＺｎＳ：Ｃｕ，Ａｕ，Ａｌ
（ＧＬ−１４）　Ｚｎ_２ＳｉＯ_４：Ｍｎ^２＋
（ＧＬ−１５）　ＺｎＳ：Ａｇ，Ｃｕ
（ＧＬ−１６）　（Ｚｎ，Ｃｄ）Ｓ：Ｃｕ
（ＧＬ−１７）　ＺｎＳ：Ｃｕ
（ＧＬ−１８）　Ｇｄ_２Ｏ_２Ｓ：Ｔｂ^３＋
（ＧＬ−１９）　Ｌａ_２Ｏ_２Ｓ：Ｔｂ^３＋
（ＧＬ−２０）　Ｙ_２ＳｉＯ_５：Ｃｅ^３＋，Ｔｂ^３＋
（ＧＬ−２１）　Ｚｎ_２ＧｅＯ_４：Ｍｎ^２＋
（ＧＬ−２２）　ＣｅＭｇＡｌ_１１Ｏ_１９：Ｔｂ^３＋
（ＧＬ−２３）　ＳｒＧａ_２Ｓ_４：Ｅｕ^２＋
（ＧＬ−２４）　ＺｎＳ：Ｃｕ，Ｃｏ
（ＧＬ−２５）　ＭｇＯ・ｎＢ_２Ｏ_３：Ｃｅ^３＋，Ｔｂ^３＋
（ＧＬ−２６）　ＬａＯＢｒ：Ｔｂ^３＋，Ｔｍ^３＋
（ＧＬ−２７）　Ｌａ_２Ｏ_２Ｓ：Ｔｂ^３＋
（ＧＬ−２８）　ＳｒＧａ_２Ｓ_４：Ｅｕ^２＋，Ｔｂ^３＋，Ｓｍ^２＋
［赤色発光無機蛍光体粒子］
（ＲＬ−１）　Ｙ_２Ｏ_２Ｓ：Ｅｕ^３＋
（ＲＬ−２）　（Ｂａ，Ｍｇ）_２ＳｉＯ_４：Ｅｕ^３＋
（ＲＬ−３）　Ｃａ_２Ｙ_８（ＳｉＯ_４）_６Ｏ_２：Ｅｕ^３＋
（ＲＬ−４）　ＬｉＹ_９（ＳｉＯ_４）_６Ｏ_２：Ｅｕ^３＋
（ＲＬ−５）　（Ｂａ，Ｍｇ）Ａｌ_１６Ｏ_２７：Ｅｕ^３＋
（ＲＬ−６）　（Ｂａ，Ｃａ，Ｍｇ）_５（ＰＯ_４）_３Ｃｌ：Ｅｕ^３＋
（ＲＬ−７）　ＹＶＯ_４：Ｅｕ^３＋
（ＲＬ−８）　ＹＶＯ_４：Ｅｕ^３＋，Ｂｉ^３＋
（ＲＬ−９）　ＣａＳ：Ｅｕ^３＋
（ＲＬ−１０）　Ｙ_２Ｏ_３：Ｅｕ^３＋
（ＲＬ−１１）　３．５ＭｇＯ，０．５ＭｇＦ_２ＧｅＯ_２：Ｍｎ^４＋
（ＲＬ−１２）　ＹＡｌＯ_３：Ｅｕ^３＋
（ＲＬ−１３）　ＹＢＯ_３：Ｅｕ^３＋
（ＲＬ−１４）　（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋
等。
【００５１】
以下で、本発明に係る蛍光体の用途を例示するが、これに限定されるものではない。本発明に係る無機蛍光体は、プラズマディスプレイパネル、フィールドエミッションディスプレイ、紫外発光有機エレクトロルミネッセンスディスプレイをはじめとするフラットパネルディスプレイ用蛍光体、カラー陰極線管用蛍光体、インクジェット用インク、電子写真トナー、ハロゲン化銀写真材料等の色材・メディア用蛍光体、増感紙用蛍光体として用いることが出来る。
【００５２】
【実施例】
以下、実施例を挙げて本発明を詳細に説明するが、本発明の態様はこれに限定されるものではない。
【００５３】
（実施例１）
〈蛍光体１の製造〉
水１，０００ｍｌを溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００５４】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］、溶液［Ｃ］をそれぞれ溶液［Ａ］の入った容器１の注加ノズル３、４より１００ｍｌ／ｍｉｎの速度で等速添加を行った。添加後４５分間熟成を行い、蛍光体前駆体１を得た。その後、蛍光体前駆体１を濾過乾燥し乾燥蛍光体前駆体１を得た。さらに、乾燥蛍光体前駆体１を１，４００℃酸化条件下で２時間焼成し蛍光体１を得た。
【００５５】
〈蛍光体２の製造〉
水１，０００ｍｌに硝酸を加えてｐＨ５．５とした溶液を溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００５６】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］、溶液［Ｃ］をそれぞれ溶液［Ａ］の入った容器１の注加ノズル３、４より１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５からアンモニアを加えながらｐＨ５．５に制御して反応を行った。添加終了後４５分間熟成を行い、蛍光体前駆体２を得た。その後、蛍光体前駆体２を濾過乾燥し乾燥蛍光体前駆体２を得た。さらに、乾燥蛍光体前駆体２を１，４００℃酸化条件下で２時間焼成し蛍光体２を得た。
【００５７】
〈蛍光体３の製造〉
水１，０００ｍｌにアンモニアを加えてｐＨ８．０とした溶液を溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００５８】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］、溶液［Ｃ］をそれぞれ溶液［Ａ］の入った容器１の注加ノズル３、４より１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５からアンモニアを加えながらｐＨ８．０に制御して反応を行った。添加終了後４５分間熟成を行い、蛍光体前駆体３を得た。その後、蛍光体前駆体３を濾過乾燥し乾燥蛍光体前駆体３を得た。さらに、乾燥蛍光体前駆体３を１，４００℃酸化条件下で２時間焼成し蛍光体３を得た。
【００５９】
〈蛍光体４の製造〉
水１，０００ｍｌにアンモニアを加えてｐＨ８．０とした溶液を溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００６０】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］、溶液［Ｃ］をそれぞれ溶液［Ａ］の入った容器１の注加ノズル３、４より１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５からアンモニアを加えながらｐＨ８．０に制御して反応を行った。添加終了後、アンモニアを用いてｐＨ１１．０にして４５分間熟成を行い、蛍光体前駆体４を得た。熟成時もセンサー６からの信号をアンモニア添加装置（図示せず）にフィードバックして、適宜アンモニアを加えながらｐＨ１１．０に制御した。その後、蛍光体前駆体４を濾過乾燥し乾燥蛍光体前駆体４を得た。さらに、乾燥蛍光体前駆体４を１，４００℃酸化条件下で２時間焼成し蛍光体４を得た。
【００６１】
〈蛍光体５の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解した溶液を溶液［Ａ］としたこと以外は蛍光体２の製造方法と同様にして、蛍光体５を得た。
【００６２】
〈蛍光体６の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解した溶液を溶液［Ａ］としたこと以外は蛍光体３の製造方法と同様にして、蛍光体６を得た。
【００６３】
〈蛍光体７の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解した溶液を溶液［Ａ］としたこと以外は蛍光体４の製造方法と同様にして、蛍光体７を得た。
【００６４】
得られた蛍光体１〜７は粉末Ｘ線回折装置で組成を確認した結果、（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋であった。蛍光体（蛍光体１〜７）に真空紫外線（１４６ｎｍ）を照射し、それぞれの発光強度を求めた。次いで、蛍光体１を１００％としたときのそれぞれの蛍光体の相対発光強度を算出した。また、電子顕微鏡により粒子の写真を撮影して平均粒径及び変動係数を算出した。結果を表１に示す。
【００６５】
【表１】

【００６６】
表１から明らかなように、本発明の製造方法を用いることにより小粒径、単分散且つ高発光強度な蛍光体を得ることが可能となった。
【００６７】
（実施例２）
〈蛍光体８の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００６８】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。添加後１２０分間熟成を行い、蛍光体前駆体８を得た。その後、蛍光体前駆体８を濾過乾燥し乾燥蛍光体前駆体８を得た。さらに、乾燥蛍光体前駆体８を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体８を得た。
【００６９】
〈蛍光体９の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００７０】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。添加後１２０分間熟成を行い、蛍光体前駆体９を得た。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号を硝酸添加装置（図示せず）にフィードバックして、注加ノズル５から硝酸を加えながらｐＨ６．５に制御して反応を行った。添加終了後１２０分間熟成を行い、蛍光体前駆体９を得た。その後、蛍光体前駆体９を濾過乾燥し乾燥蛍光体前駆体９を得た。さらに、乾燥蛍光体前駆体９を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体９を得た。
【００７１】
〈蛍光体１０の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００７２】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５からアンモニアを加えながらｐＨ１１．０に制御して反応を行った。添加終了後１２０分間熟成を行い、蛍光体前駆体１０を得た。その後、蛍光体前駆体１０を濾過乾燥し乾燥蛍光体前駆体１０を得た。さらに、乾燥蛍光体前駆体１０を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体１０を得た。
【００７３】
〈蛍光体１１の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００７４】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。このとき、センサー６（この場合はｐＨセンサーを用いた）からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５からアンモニアを加えながらｐＨ１１．０に制御して反応を行った。添加終了後、アンモニアを用いてｐＨ１３．０にして１２０分間熟成を行い、蛍光体前駆体１１を得た。熟成時もセンサー６からの信号をアンモニア添加装置（図示せず）にフィードバックして、注加ノズル５から適宜アンモニアを加えながらｐＨ１３．０に制御した。その後、蛍光体前駆体１１を濾過乾燥し乾燥蛍光体前駆体１１を得た。さらに、乾燥蛍光体前駆体１１を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体１１を得た。
【００７５】
〈蛍光体１２の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体９の製造方法と同様にして蛍光体１２を得た。
【００７６】
〈蛍光体１３の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体１０の製造方法と同様にして蛍光体１３を得た。
【００７７】
〈蛍光体１４の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体１１の製造方法と同様にして蛍光体１４を得た。
【００７８】
得られた蛍光体８〜１４は粉末Ｘ線回折装置で組成を確認した結果、Ｚｎ_２ＳｉＯ_４：Ｍｎ^２＋であった。蛍光体（蛍光体８〜１４）に真空紫外線（１４６ｎｍ）を照射し、それぞれの発光強度を求めた。次いで、蛍光体８を１００％としたときのそれぞれの蛍光体の相対発光強度を算出した。また、電子顕微鏡により粒子の写真を撮影して平均粒径及び変動係数を算出した。結果を表２に示す。
【００７９】
【表２】

【００８０】
表２から明らかなように、本発明の製造方法を用いることにより小粒径、単分散且つ高発光強度な蛍光体を得ることが可能となった。
【００８１】
（実施例３）
〈蛍光体１５の製造〉
水１，０００ｍｌを溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００８２】
図１の容器１に溶液［Ａ］を入れ温度を１５℃に保ち、撹拌機構２を用いて撹拌を行った。その状態で同じく１５℃に保った溶液［Ｂ］及び溶液［Ｃ］を溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合は温度センサーを用いた）からの信号を温度制御装置（図示せず）にフィードバックして、１５℃に制御しながら反応を行った。添加終了後４５分間熟成を行い、蛍光体前駆体１５を得た。その後、蛍光体前駆体１５を濾過乾燥し乾燥蛍光体前駆体１５を得た。さらに、乾燥蛍光体前駆体１５を１，４００℃酸化条件下で２時間焼成し蛍光体１５を得た。
【００８３】
〈蛍光体１６の製造〉
水１，０００ｍｌを溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００８４】
図１の容器１に溶液［Ａ］を入れ温度を４５℃に保ち、撹拌機構２を用いて撹拌を行った。その状態で同じく４５℃に保った溶液［Ｂ］及び溶液［Ｃ］を溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合は温度センサーを用いた）からの信号を温度制御装置（図示せず）にフィードバックして、４５℃に制御しながら反応を行った。添加終了後４５分間熟成を行い、蛍光体前駆体１６を得た。その後、蛍光体前駆体１６を濾過乾燥し乾燥蛍光体前駆体１６を得た。さらに、乾燥蛍光体前駆体１６を１，４００℃酸化条件下で２時間焼成し蛍光体１６を得た。
【００８５】
〈蛍光体１７の製造〉
水１，０００ｍｌを溶液［Ａ］とした。水５００ｍｌにイットリウムのイオン濃度が０．４６５９ｍｏｌ／ｌ、ガドリニウムのイオン濃度が０．２７１６ｍｏｌ／ｌ、ユウロピウムのイオン濃度が０．０３８８ｍｏｌ／ｌとなるように硝酸イットリウム六水和物、硝酸ガドリニウム、硝酸ユウロピウム六水和物を溶解し溶液［Ｂ］とした。水５００ｍｌにホウ素のイオン濃度が０．７７６３ｍｏｌ／ｌとなるようにホウ酸を溶解し溶液［Ｃ］とした。
【００８６】
図１の容器１に溶液［Ａ］を入れ温度を４５℃に保ち、撹拌機構２を用いて撹拌を行った。その状態で同じく４５℃に保った溶液［Ｂ］及び溶液［Ｃ］を溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ１００ｍｌ／ｍｉｎの速度で等速添加して白色沈殿を得た。このとき、センサー６（この場合は温度センサーを用いた）からの信号を温度制御装置（図示せず）にフィードバックして、４５℃に制御しながら反応を行った。添加終了後、８０℃に加温して４５分間熟成を行い、蛍光体前駆体１７を得た。熟成時もセンサー６からの信号を温度制御装置（図示せず）にフィードバックして８０℃に制御した。その後、蛍光体前駆体１７を濾過乾燥し乾燥蛍光体前駆体１７を得た。さらに、乾燥蛍光体前駆体１７を１，４００℃酸化条件下で２時間焼成し蛍光体１７を得た。
【００８７】
〈蛍光体１８の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解して溶液［Ａ］を調整したこと以外は蛍光体１５の製造方法と同様にして、蛍光体１８を得た。
【００８８】
〈蛍光体１９の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解して溶液［Ａ］を調整したこと以外は蛍光体１６の製造方法と同様にして、蛍光体１９を得た。
【００８９】
〈蛍光体２０の製造〉
水１，０００ｍｌに低分子ゼラチン３０ｇ（平均分子量約１０万）を溶解して溶液［Ａ］を調整したこと以外は蛍光体１７の製造方法と同様にして、蛍光体２０を得た。
【００９０】
得られた蛍光体１５〜２０は粉末Ｘ線回折装置で組成を確認した結果、（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋であった。蛍光体（蛍光体１５〜２０）に真空紫外線（１４６ｎｍ）を照射し、それぞれの発光強度を求めた。次いで、実施例１で製造した蛍光体１を１００％としたときのそれぞれの蛍光体の相対発光強度を算出した。また、電子顕微鏡により粒子の写真を撮影して平均粒径及び変動係数を算出した。結果を表３に示す。
【００９１】
【表３】

【００９２】
表３から明らかなように、本発明の製造方法を用いることにより小粒径、単分散且つ高発光強度な蛍光体を得ることが可能となった。
【００９３】
（実施例４）
〈蛍光体２１の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００９４】
図１の容器１に溶液［Ａ］を入れ温度を２５℃に保ち、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、同じく２５℃に保った溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、同じく２５℃に保った溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。添加後１２０分間熟成を行い、蛍光体前駆体２１を得た。その後、蛍光体前駆体２１を濾過乾燥し乾燥蛍光体前駆体２１を得た。さらに、乾燥蛍光体前駆体２１を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体２１を得た。
【００９５】
〈蛍光体２２の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００９６】
図１の容器１に溶液［Ａ］を入れ、温度を５５℃に保ち撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、同じく５５℃に保った溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、同じく５５℃に保った溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。添加後１２０分間熟成を行い、蛍光体前駆体２２を得た。このとき、センサー６（この場合は温度センサーを用いた）からの信号を温度制御装置（図示せず）にフィードバックして、５５℃に制御しながら反応を行った。添加終了後１２０分間熟成を行い、蛍光体前駆体２２を得た。その後、蛍光体前駆体２２を濾過乾燥し乾燥蛍光体前駆体２２を得た。さらに、乾燥蛍光体前駆体２２を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体２２を得た。
【００９７】
〈蛍光体２３の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【００９８】
図１の容器１に溶液［Ａ］を入れ、温度を５５℃に保ち撹拌機構２を用いて撹拌を行った。その状態で溶液［Ａ］の入った容器１の注加ノズル３、４からそれぞれ、同じく５５℃に保った溶液［Ｂ］を８０ｍｌ／ｍｉｎの速度で、同じく５５℃に保った溶液［Ｃ］を２０ｍｌ／ｍｉｎの速度で等速添加を行った。このとき、センサー６（この場合は温度センサーを用いた）からの信号を温度制御装置（図示せず）にフィードバックして、５５℃に制御しながら反応を行った。添加終了後、８０℃に加温して１２０分間熟成を行い、蛍光体前駆体２３を得た。熟成時も温度センサー６からの信号を温度制御装置（図示せず）にフィードバックして８０℃に制御した。その後、蛍光体前駆体２３を濾過乾燥し乾燥蛍光体前駆体２３を得た。さらに、乾燥蛍光体前駆体２３を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体２３を得た。
【００９９】
〈蛍光体２４の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２１の製造方法と同様にして蛍光体２４を得た。
【０１００】
〈蛍光体２５の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２２の製造方法と同様にして蛍光体２５を得た。
【０１０１】
〈蛍光体２６の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２３の製造方法と同様にして蛍光体２６を得た。
【０１０２】
得られた蛍光体２１〜２６は粉末Ｘ線回折装置で組成を確認した結果、Ｚｎ_２ＳｉＯ_４：Ｍｎ^２＋であった。蛍光体（蛍光体２１〜２６）に真空紫外線（１４６ｎｍ）を照射し、それぞれの発光強度を求めた。次いで、実施例２で製造した蛍光体８を１００％としたときのそれぞれの蛍光体の相対発光強度を算出した。また、電子顕微鏡により粒子の写真を撮影して平均粒径及び変動係数を算出した。結果を表４に示す。
【０１０３】
【表４】

【０１０４】
表４から明らかなように、本発明の製造方法を用いることにより小粒径、単分散且つ高発光強度な蛍光体を得ることが可能となった。
【０１０５】
（実施例５）
〈蛍光体２７の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【０１０６】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］を溶液［Ａ］の入った容器の注加ノズル３から添加した。このとき、センサー６（この場合は亜鉛イオン濃度センサーを用いた）からの信号を塩化亜鉛添加装置（図示せず）にフィードバックして、亜鉛イオン濃度が２．２×１０^−１ｍｏｌ／ｌになるように制御しながら反応を行った。溶液［Ｃ］は２０ｍｌ／ｍｉｎの速度で注加ノズル４から等速添加を行った。添加終了後１２０分間熟成を行い、蛍光体前駆体２７を得た。その後、蛍光体前駆体２７を濾過乾燥し乾燥蛍光体前駆体２７を得た。さらに、乾燥蛍光体前駆体２７を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体２７を得た。
【０１０７】
〈蛍光体２８の製造〉
亜鉛イオン濃度が４．８×１０^−２ｍｏｌ／ｌになるように制御しながら反応を行うこと以外は、蛍光体２７の製造方法と同様にして蛍光体２８を得た。
【０１０８】
〈蛍光体２９の製造〉
水８００ｍｌに珪素のイオン濃度が０．４６５５ｍｏｌ／ｌとなるようにメタ珪酸ナトリウムを溶解し溶液［Ａ］とした。水８００ｍｌに亜鉛のイオン濃度が０．８８４５ｍｏｌ／ｌとなるように塩化亜鉛を溶解し溶液［Ｂ］とした。水２００ｍｌにマンガンのイオン濃度が０．１８６２ｍｏｌ／ｌとなるように塩化マンガン四水和物を溶解し溶液［Ｃ］とした。
【０１０９】
図１の容器１に溶液［Ａ］を入れ、撹拌機構２を用いて撹拌を行った。その状態で溶液［Ｂ］を溶液［Ａ］の入った容器の注加ノズル３から添加した。このとき、センサー６（この場合は亜鉛イオン濃度センサーを用いた）からの信号を塩化亜鉛添加装置（図示せず）にフィードバックして、亜鉛イオン濃度が４．８×１０^−２ｍｏｌ／ｌになるように制御しながら反応を行った。溶液［Ｃ］は注加ノズル４から２０ｍｌ／ｍｉｎの速度で等速添加を行った。添加終了後、亜鉛イオン濃度を１×１０^−５ｍｏｌ／ｌに変更して１２０分間熟成を行い、蛍光体前駆体２９を得た。熟成時もセンサー６からの信号を塩化亜鉛添加装置（図示せず）にフィードバックして６．７×１０^−４ｍｏｌ／ｌに制御した。その後、蛍光体前駆体２９を濾過乾燥し乾燥蛍光体前駆体２９を得た。さらに、乾燥蛍光体前駆体２９を１，０５０℃窒素雰囲気下で３時間焼成し蛍光体２９を得た。
【０１１０】
〈蛍光体３０の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２７の製造方法と同様にして蛍光体３０を得た。
【０１１１】
〈蛍光体３１の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２８の製造方法と同様にして蛍光体３１を得た。
【０１１２】
〈蛍光体３２の製造〉
低分子ゼラチン（平均分子量約１０万）を溶液［Ａ］、溶液［Ｂ］、溶液［Ｃ］にそれぞれ３質量％ずつ加えて溶解したこと以外は、蛍光体２９の製造方法と同様にして蛍光体３２を得た。
【０１１３】
得られた蛍光体２７〜３２は粉末Ｘ線回折装置で組成を確認した結果、Ｚｎ_２ＳｉＯ_４：Ｍｎ^２＋であった。蛍光体（蛍光体２７〜３２）に真空紫外線（１４６ｎｍ）を照射し、それぞれの発光強度を求めた。次いで、実施例２で製造した蛍光体８を１００％としたときのそれぞれの蛍光体の相対発光強度を算出した。また、電子顕微鏡により粒子の写真を撮影して平均粒径及び変動係数を算出した。結果を表５に示す。
【０１１４】
【表５】

【０１１５】
表５から明らかなように、本発明の製造方法を用いることにより小粒径、単分散且つ高発光強度な蛍光体を得ることが可能となった。
【０１１６】
【発明の効果】
粒子径が小さく、且つ粒子径分布が狭く、さらには発光強度が良好な蛍光体の製造方法を提供することができた。
【図面の簡単な説明】
【図１】本発明における蛍光体前駆体の生成装置の一例を示す概念図である。
【符号の説明】
１　容器
２　撹拌機構
３、４、５　注加ノズル
６　センサー[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a phosphor precursor produced using a liquid phase method, a phosphor produced by firing the phosphor precursor, and an apparatus for producing the phosphor precursor. Further, the present invention is applicable to various flat panel displays such as plasma display panels, cathode ray tubes, fluorescent lamps, radiographic intensifying screens, inkjet inks, electrophotographic toners, and phosphors that can be suitably used for silver halide photographic materials. About.
[0002]
[Prior art]
In recent years, with the progress of the information society, various flat panel displays such as plasma display panels and color cathode ray tubes such as color cathode ray tubes have large screens and high contrast as symbolized by high definition cathode ray tubes and high definition display tubes. With the progress of image formation, it is necessary to form finer pixels on a face plate so as to form a high-definition screen. For this reason, the phosphor has been required to have various improved properties such as improved light emission luminance and improved adhesion to the face plate surface.
[0003]
The conventional phosphors for flat panel displays use particles having a particle size of about 2 to 7 μm developed for color cathode ray tubes, and the excitation wavelengths optimized for each flat panel display have not been developed. Therefore, improvement of various characteristics is required. In particular, a phosphor having a small particle size, monodispersion, and high luminance has been demanded in accordance with high definition of a display in the future.
[0004]
As a general method for producing a phosphor, a solid phase method in which a compound containing the element constituting the phosphor matrix and a compound containing the activator element are mixed in a predetermined amount and then fired to perform a solid-solid reaction, There is a liquid phase method in which a phosphor precursor precipitate obtained by mixing together a solution containing the element constituting the above and a solution containing the activator element is subjected to solid-liquid separation and then fired.
[0005]
In order to increase the luminous efficiency and yield of the phosphor, it is necessary to make the phosphor composition as close as possible to the stoichiometric composition, but the solid phase method produces a phosphor with a purely stoichiometric composition. Difficult to do. Since the solid-phase method is a solid-solid reaction, surplus impurities that do not react and secondary salts generated by the reaction often remain, making it difficult to obtain a stoichiometrically high-purity phosphor.
[0006]
In addition, the phosphor obtained by the solid phase method has a relatively wide particle size distribution, and particularly when fired using a large amount of flux, a phosphor having a wide particle size distribution close to a normal distribution can be obtained. When a phosphor film is formed using such a phosphor, it is not preferable that a large amount of fine particles or coarse particles exist in order to obtain a high-luminance and dense phosphor film. These fine particles and coarse particles are removed by a classification operation as necessary, but the classification operation is poor in workability and lowers the yield.In particular, the formation of coarse particles reduces the yield of particles having a desired particle size. It has a significant effect and cannot always be reliably removed. Therefore, it is important that unnecessary fine particles and coarse particles, especially coarse particles are not generated during firing in forming a fluorescent film for a high definition cathode ray tube.
[0007]
In addition, the phosphor obtained by the solid phase method has lower luminous efficiency and luminous luminance as the particle size becomes smaller. Therefore, phosphors having sufficient luminous efficiency and luminous luminance at 1 μm or less are hardly supplied. Is the fact. Several methods for producing a phosphor having a particle size of 1 μm or less have been disclosed, but particles having a size of 1 μm or less have been obtained by a classification operation as disclosed in Japanese Patent Application Laid-Open No. 8-81678 or the like. The problem of reduced yield occurs.
[0008]
In addition, in each step of the phosphor production, agglomeration increases the particle size of the particles, which is a great hindrance to the atomization of the phosphor. There is only a description of a sintering inhibitor in Japanese Unexamined Patent Publication No. Hei 6-306358 or the like, and its effect is not sufficient.
[0009]
On the other hand, in the case of producing a phosphor by a liquid phase method, first, a precipitate that is a phosphor precursor is generated, and then the phosphor precursor is fired to be a phosphor. In the liquid phase method, a reaction occurs due to element ions constituting the phosphor, so that it is easy to obtain a stoichiometrically high-purity phosphor, but the phosphor particle size, particle shape, particle size distribution, emission characteristics, etc. The properties greatly depend on the properties of the phosphor precursor. Therefore, in order to obtain a desired phosphor, it is necessary to consider control of the particle shape and particle size distribution, elimination of impurities, and the like during the generation of the phosphor precursor.
[0010]
Therefore, a number of improved methods for producing a phosphor by a liquid phase method have been proposed. For example, Japanese Patent Application Laid-Open No. 2001-172627 discloses a method for producing a rare earth phosphate phosphor for a fluorescent lamp by adding a solution in which ions of a rare earth element and phosphate ions coexist to an aqueous solution whose pH is controlled from 1.0 to 2.0. To produce a rare earth phosphate phosphor precursor. Japanese Patent Application Laid-Open No. Hei 9-71415 discloses a method for producing a rare earth oxide, in which a reaction between a rare earth ion and an oxalate ion is carried out in a state maintained at -5 ° C or more and 20 ° C or less to produce a spherical rare earth oxide. Is disclosed. However, in these methods, although a high purity composition is obtained as compared with a phosphor obtained by a solid phase method, and there are advantages such as obtaining spherical particles, a phosphor having both a small particle size and high brightness is obtained. Was still inadequate.
[0011]
[Problems to be solved by the invention]
The present invention provides a method for producing a phosphor obtained by calcining a phosphor precursor produced using a liquid phase method, wherein the particle diameter is small, the particle diameter distribution is narrow, and the emission intensity is good. A method for producing a phosphor is provided.
[0012]
[Means for Solving the Problems]
The present inventors have intensively studied a method for producing a phosphor by a liquid phase method in order to achieve the above object, and as a result, by controlling the conditions for producing the phosphor precursor, the particle diameter is small, and the particle diameter is small. The present inventors have found that a phosphor having a narrow distribution and good emission intensity can be manufactured, and have completed the present invention.
[0013]
The configuration of the present invention is as follows.
(1) In the method for producing a phosphor in which a phosphor is obtained by baking the phosphor precursor after the phosphor precursor is generated in a liquid phase, the time from the start to the end of the production of the phosphor precursor Producing a phosphor precursor while controlling the pH of at least a part of the phosphor.
[0014]
(2) The method for producing a phosphor according to (1), wherein the pH control is performed in a range of pH 7 to pH 14.
[0015]
(3) The method for producing a phosphor according to (1) or (2), wherein the pH control is performed twice or more.
[0016]
(4) In the method for producing a phosphor in which a phosphor is obtained by baking the phosphor precursor after producing the phosphor precursor in the liquid phase, the time from the start to the end of the production of the phosphor precursor Producing a phosphor precursor while controlling the temperature of at least a part of the phosphor.
[0017]
(5) The method for producing a phosphor according to (4), wherein the temperature control is performed in a range of 30 ° C. to 70 ° C.
[0018]
(6) The method for producing a phosphor according to (4) or (5), wherein the temperature control is performed twice or more.
[0019]
(7) In the method for producing a phosphor in which a phosphor is obtained by baking the phosphor precursor after producing the phosphor precursor in the liquid phase, the time from the start to the end of the production of the phosphor precursor A method for producing a phosphor, characterized in that the phosphor precursor is generated while controlling the ion concentration of at least one of the constituent elements of the phosphor precursor at least in part.
[0020]
(8) The method for producing a phosphor according to (7), wherein the ion concentration control is performed twice or more.
[0021]
(9) The method for producing a phosphor according to any one of (1) to (8), wherein the phosphor precursor is generated in the presence of a binder.
[0022]
(10) A phosphor precursor producing apparatus for producing a phosphor precursor by a liquid phase method, wherein a pH sensor is provided in a reaction vessel for producing the phosphor precursor. Precursor generator.
[0023]
(11) A phosphor precursor producing apparatus for producing a phosphor precursor by a liquid phase method, wherein a temperature sensor is provided in a reaction vessel for producing the phosphor precursor. Precursor generator.
[0024]
(12) A phosphor precursor producing apparatus for producing a phosphor precursor by a liquid phase method, wherein at least two or more types of sensors are provided in a reaction vessel for producing the phosphor precursor. Phosphor precursor generating apparatus.
[0025]
(13) The phosphor precursor generator according to (12), wherein the sensors are at least two types selected from a temperature sensor, a pH sensor, and a metal ion concentration sensor.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
[0027]
The phosphor precursor is an intermediate product of the phosphor, and the phosphor is obtained by firing the phosphor precursor at a predetermined temperature.
[0028]
The method for producing the phosphor used in the present invention will be described.
The present inventors control the conditions for producing the phosphor precursor, in particular, various conditions such as pH, temperature, ion concentration of the constituent elements of the phosphor precursor, and binder in the time from the start to the end of the production of the phosphor precursor. As a result, it has been found that a phosphor having a small particle size and a narrow particle size distribution and excellent light emission intensity can be manufactured. In the method for producing a phosphor of the present invention, a solution containing an element constituting a phosphor matrix and a solution containing an activator element are mixed together to generate a precipitate of a phosphor precursor in a solution, A liquid phase method in which the body is separated into solid and liquid and then fired is preferably used.
[0029]
In the present invention, the method for precipitating the phosphor precursor is not particularly limited, and it can be preferably produced by any method such as a reaction crystallization method, a coprecipitation method, and a Sol-Gel method. In addition, in order to obtain the kind and desired characteristics of the phosphor, it is preferable to appropriately adjust the addition speed, the addition position, the stirring conditions, and the like of the raw material solution and the like.
[0030]
FIG. 1 shows an example of a conceptual diagram of an apparatus for producing a phosphor precursor according to the present invention. However, the present invention is not limited to this example, and all aspects are preferably used. In FIG. 1, the container 1 initially contains the raw material solution [A]. Although the stirring mechanism 2 is illustrated as having a rotatable shaft with wings attached thereto, the mechanism can have any conventional shape. While operating the stirring mechanism 2, the phosphor raw material solution [B] is poured into the container 1 through the pouring nozzle 3, and at the same time, the phosphor raw material solution [C] is poured into the container 1 through the pouring nozzle 4. At this time, the characteristic value in the container 1 that changes with the reaction is measured by the sensor 6, and the necessary addition amount is fed back to the adjustment liquid adding device or the like (not shown) so that the desired characteristic value is obtained. The characteristic value is controlled in real time by pouring the adjustment liquid into the container 1 from the addition nozzle 5. The characteristic value may not be changed during the addition time of the raw material solution, or may be changed as needed. After completion of the addition of the raw material solution, aging treatment is performed for a certain period of time to complete the generation of the phosphor precursor. During aging, characteristic values such as pH, temperature, and ion concentration may be the same as those at the time of adding the raw material solution, or may be appropriately changed as necessary.
[0031]
The raw material solution referred to in the present invention refers to a solution containing at least one of the constituent element ions of the phosphor, a solvent, and a binder.
[0032]
In the present invention, it is preferable to generate the phosphor precursor while controlling the pH at least a part of the time from the start to the end of the production of the phosphor precursor, and further, while controlling the pH value in the range of pH 7 to pH 14. It is preferable to generate a phosphor precursor, and it is the most preferable embodiment to perform pH control at least twice or more to generate a phosphor precursor.
[0033]
In the present invention, it is preferable to generate the phosphor precursor while controlling the temperature at least a part of the time from the start to the end of the production of the phosphor precursor, and further control the temperature in the range of 30 ° C to 70 ° C. It is preferable to generate the phosphor precursor while performing the temperature control at least twice or more to generate the phosphor precursor.
[0034]
In the present invention, it is preferable to generate the phosphor precursor while controlling the ion concentration of at least one type of the constituent elements of the phosphor for at least a part of the time from the start to the end of the production of the phosphor precursor. Ion concentration of 1 × 10^-61 x 10 from mol / l²It is preferable to generate the phosphor precursor while controlling it in the mol / l range, and it is the most preferable embodiment to control the ion concentration at least twice or more to generate the phosphor precursor.
[0035]
In the present invention, the number of injection nozzles is not limited to three systems, but can be appropriately increased or decreased according to the type and characteristics of the phosphor to be manufactured. In the present invention, it is preferable to use a pH sensor as that used for the sensor. In another aspect, the present invention preferably uses a temperature sensor as that used for the sensor. In still another aspect, the present invention preferably uses an ion concentration sensor for measuring the ion concentration of at least one kind of the constituent elements of the phosphor as the sensor. In a preferred embodiment of the present invention, the type of sensor is not limited to one type, and at least two types are used. Depending on the type and characteristics of the phosphor, pH, temperature, and ion concentration can be appropriately used in combination. Most preferably, all sensors are used to generate the phosphor precursor.
[0036]
Further, the crystal nuclei generated in another container may be poured into the container 1 in advance, and further, the crystal nuclei continuously reacted by another mixer may be continuously supplied to the container 1. There may be.
[0037]
The present invention preferably produces a phosphor precursor in the presence of a binder. The binder in the present invention functions to prevent agglomeration of the particles, and clearly has a different function from the organic polymer used for crystal habit control disclosed in JP-A-2001-329262.
[0038]
As the binder in the present invention, a known polymer compound, whether natural or synthetic, can be used. At that time, the average molecular weight of the binder is preferably 10,000 or more, more preferably 10,000 or more and 300,000 or less, and particularly preferably 10,000 or more and 30,000 or less. The binder in the present invention is preferably a protein, and particularly preferably gelatin. Further, it is not necessary to have a single composition, and various binders may be mixed.
[0039]
In the present invention, the solid-liquid separation method of the phosphor precursor is not particularly limited, and centrifugation, suction filtration, and the like are preferably used. Further, the phosphor precursor solution may be directly processed in a baking furnace such as a dryer or a spray pyrolysis furnace. In the present invention, the method for drying the phosphor precursor is not particularly limited, and any method such as vacuum drying, flash drying, fluidized bed drying, and spray drying may be used.
[0040]
Furthermore, in the present invention, the firing temperature and the firing time of the phosphor precursor are not particularly limited, and can be appropriately selected according to the type of the phosphor. The gas atmosphere during firing may be any of an oxidizing atmosphere, a reducing atmosphere, or an inert atmosphere, and can be appropriately selected according to the purpose. The firing device is not particularly limited, and a known firing device can be used. For example, a box furnace, a crucible furnace, a rotary kiln, a spray pyrolysis furnace and the like are preferably used.
[0041]
In the present invention, a sintering inhibitor may or may not be added. When it is added, it may be added as a slurry at the time of producing the phosphor precursor, or a method in which a powdery substance is mixed with a dried phosphor precursor and fired is also preferably used. Furthermore, the sintering inhibitor is not particularly limited, and is appropriately selected depending on the type of the phosphor and the sintering conditions. For example, when firing at 800 ° C. or less depending on the firing temperature range of the phosphor, TiO 2 is used.₂Metal oxides such as SiO 2 for baking below 1,000 ° C.₂However, for sintering below 1,700 ° C, Al₂O₃Is preferably used. In the present invention, it is desirable to wash the phosphor after firing, but it is not always necessary to wash.
[0042]
The phosphor according to the present invention preferably has an average particle size of 1.0 μm or less, more preferably 0.8 μm or less, further preferably 0.5 μm or less, and more preferably 0.01 μm or more and 0.1 μm or less. Most preferably, it is 3 μm or less. The term “average particle size” as used herein refers to the length of the edge of a particle when the particle is a cubic or octahedral so-called normal crystal. In the case of non-normal crystals, for example, in the case of spherical, rod-shaped, or tabular particles, the diameter indicates the diameter of a sphere equivalent to the particle volume.
[0043]
In the present invention, the shape of the phosphor particles is not particularly limited, but is preferably a cubic shape, more preferably an octahedral shape, and more preferably a spherical shape.
[0044]
In the phosphor of the present invention, the coefficient of variation of the particle size distribution is preferably 100% or less, more preferably 50% or less, and most preferably 30% or less. Here, the variation coefficient of the particle size is a value defined by the following equation.
[0045]
(Standard deviation of particle size / average value of particle size) × 100 = Area of particle distribution (coefficient of variation) [%]
In the present invention, the surface of the phosphor may be modified or the dispersibility may be improved by a surface modifier, a surfactant, a matting agent such as fine particle silica gel, aerosil, or alumina, if necessary.
[0046]
The composition of the inorganic phosphor particles according to the present invention is described in, for example, JP-A-50-6410, JP-A-61-65226, JP-A-64-22987, JP-A-64-60671, and JP-A-1-168911. And there is no particular limitation, but the crystal parent Y₂O₂S, Zn₂SiO₄, Ca₅(PO₄)₃Metal oxides represented by Cl and the like and sulfides represented by ZnS, SrS, CaS and the like, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, etc. It is preferable to use a rare earth metal ion or a metal ion such as Ag, Al, Mn or Sb as an activator or a coactivator.
[0047]
Preferred examples of the crystal base include, for example, ZnS, Y₂O₂S, Y₃Al₅O₁₂, Y₂SiO₅, Zn₂SiO₄, Y₂O₃, BaMgAl₁₀O₁₇, BaAl₁₂O₁₉, (Ba, Sr, Mg) O.BaAl₂O₃, (Y, Gd) BO₃, YO₃, (Zn, Cd) S, SrGa₂S₄, SrS, GaS, SnO₂, Ca₁₀(PO₄)₆(F, Cl)₂, (Ba, Sr) (Mg, Mn) Al₁₀O₁₇, (Sr, Ca, Ba, Mg)₁₀(PO₄)₆Cl₂, (La, Ce) PO₄, CeMgAl₁₁O₁₉, GdMgB₅O₁₀, Sr₂P₂O₇, Sr₄Al₁₄O₂₅And the like.
[0048]
The above-mentioned crystal base and activator or co-activator may be partially replaced with homologous elements, and there is no particular limitation on the element composition.
[0049]
Examples of the compound of the inorganic phosphor particles are shown below, but the present invention is not limited to these compounds.
[0050]
[Blue-emitting inorganic fluorescent compound]
(BL-1) @Sr₂P₂O₇: Sn⁴⁺
(BL-2) Sr₄Al₁₄O₂₅: Eu²⁺
(BL-3) BaMgAl₁₀O₁₇: Eu²⁺
(BL-4) @SrGa₂S₄: Ce³⁺
(BL-5) @CaGa₂S₄: Ce³⁺
(BL-6) (Ba, Sr) (Mg, Mn) Al₁₀O₁₇: Eu²⁺
(BL-7) (Sr, Ca, Ba, Mg)₁₀(PO₄)₆Cl₂: Eu²⁺
(BL-8) ZnS: Ag
(BL-9) @CaWO₄
(BL-10) @Y₂SiO₅: Ce³⁺
(BL-11) ZnS: Ag, Ga, Cl
(BL-12) @Ca₂B₅O₉Cl: Eu²⁺
(BL-13) BaMgAl₁₄O₂₃: Eu²⁺
(BL-14) BaMgAl₁₀O₁₇: Eu²⁺, Tb³⁺, Sm²⁺
(BL-15) BaMgAl₁₄O₂₃: Sm²⁺
(BL-16) @Ba₂Mg₂Al₁₂O₂₂: Eu²⁺
(BL-17) @Ba₂Mg₄Al₈O₁₈: Eu²⁺
(BL-18) Ba₃Mg₅Al₁₈O₃₅: Eu²⁺
(BL-19) (Ba, Sr, Ca) (Mg, Zn, Mn) Al₁₀O₁₇: Eu²⁺
[Green-emitting inorganic phosphor particles]
(GL-1) (Ba, Mg) Al₁₆O₂₇: Eu²⁺, Mn²⁺
(GL-2) Sr₄Al₁₄O₂₅: Eu²⁺
(GL-3) (Sr, Ba) Al₂Si₂O₈: Eu²⁺
(GL-4) (Ba, Mg)₂SiO₄: Eu²⁺
(GL-5) Y₂SiO₅: Ce³⁺, Tb³⁺
(GL-6) Sr₂P₂O₇-Sr₂B₂O₅: Eu²⁺
(GL-7) (Ba, Ca, Mg)₅(PO₄)₃Cl: Eu²⁺
(GL-8) Sr₂Si₃O₈−₂SrCl₂: Eu²⁺
(GL-9) Zr₂SiO₄, MgAl₁₁O₁₉: Ce³⁺, Tb³⁺
(GL-10) Ba₂SiO₄: Eu²⁺
(GL-11) ZnS: Cu, Al
(GL-12) (Zn, Cd) S: Cu, Al
(GL-13) ZnS: Cu, Au, Al
(GL-14) Zn₂SiO₄: Mn²⁺
(GL-15) ZnS: Ag, Cu
(GL-16) (Zn, Cd) S: Cu
(GL-17) ZnS: Cu
(GL-18) Gd₂O₂S: Tb³⁺
(GL-19) @La₂O₂S: Tb³⁺
(GL-20) Y₂SiO₅: Ce³⁺, Tb³⁺
(GL-21) @Zn₂GeO₄: Mn²⁺
(GL-22) CeMgAl₁₁O₁₉: Tb³⁺
(GL-23) SrGa₂S₄: Eu²⁺
(GL-24) ZnS: Cu, Co
(GL-25) MgO · nB₂O₃: Ce³⁺, Tb³⁺
(GL-26) @LaOBr: Tb³⁺, Tm³⁺
(GL-27) @La₂O₂S: Tb³⁺
(GL-28) SrGa₂S₄: Eu²⁺, Tb³⁺, Sm²⁺
[Red-emitting inorganic phosphor particles]
(RL-1) Y₂O₂S: Eu³⁺
(RL-2) (Ba, Mg)₂SiO₄: Eu³⁺
(RL-3) @Ca₂Y₈(SiO₄)₆O₂: Eu³⁺
(RL-4) @LiY₉(SiO₄)₆O₂: Eu³⁺
(RL-5) (Ba, Mg) Al₁₆O₂₇: Eu³⁺
(RL-6) (Ba, Ca, Mg)₅(PO₄)₃Cl: Eu³⁺
(RL-7) @YVO₄: Eu³⁺
(RL-8) @YVO₄: Eu³⁺, Bi³⁺
(RL-9) @CaS: Eu³⁺
(RL-10) Y₂O₃: Eu³⁺
(RL-11) 3.5MgO, 0.5MgF₂GeO₂: Mn⁴⁺
(RL-12) @YAlO₃: Eu³⁺
(RL-13) @YBO₃: Eu³⁺
(RL-14) (Y, Gd) BO₃: Eu³⁺
etc.
[0051]
Hereinafter, the use of the phosphor according to the present invention will be exemplified, but the present invention is not limited thereto. The inorganic phosphor according to the present invention includes a flat panel display phosphor including a plasma display panel, a field emission display, an ultraviolet light emitting organic electroluminescence display, a color cathode ray tube phosphor, an ink jet ink, an electrophotographic toner, It can be used as a phosphor for color materials and media such as silver photographic materials, and a phosphor for intensifying screen.
[0052]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples, but embodiments of the present invention are not limited thereto.
[0053]
(Example 1)
<Production of phosphor 1>
1,000 ml of water was used as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0054]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] and the solution [C] were added at a constant rate of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A]. After the addition, the mixture was aged for 45 minutes to obtain a phosphor precursor 1. Thereafter, the phosphor precursor 1 was filtered and dried to obtain a dried phosphor precursor 1. Further, the dried phosphor precursor 1 was fired at 1,400 ° C. under oxidizing conditions for 2 hours to obtain phosphor 1.
[0055]
<Production of phosphor 2>
A solution [A] was prepared by adding nitric acid to 1,000 ml of water to adjust the pH to 5.5. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0056]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] and the solution [C] were added at a constant speed of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] to obtain a white precipitate. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to an ammonia adding device (not shown) to control the reaction to pH 5.5 while adding ammonia from the injection nozzle 5 to perform the reaction. went. After completion of the addition, the mixture was aged for 45 minutes to obtain phosphor precursor 2. Thereafter, the phosphor precursor 2 was filtered and dried to obtain a dried phosphor precursor 2. Further, the dried phosphor precursor 2 was fired at 1,400 ° C. under oxidizing conditions for 2 hours to obtain phosphor 2.
[0057]
<Production of phosphor 3>
A solution adjusted to pH 8.0 by adding ammonia to 1,000 ml of water was designated as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0058]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] and the solution [C] were added at a constant rate of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] to obtain a white precipitate. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to an ammonia adding device (not shown), and the pH is controlled to 8.0 while adding ammonia from the injection nozzle 5 to perform a reaction. went. After completion of the addition, aging was performed for 45 minutes to obtain phosphor precursor 3. Thereafter, the phosphor precursor 3 was filtered and dried to obtain a dried phosphor precursor 3. Further, the dried phosphor precursor 3 was fired at 1,400 ° C. under oxidizing conditions for 2 hours to obtain phosphor 3.
[0059]
<Production of phosphor 4>
A solution adjusted to pH 8.0 by adding ammonia to 1,000 ml of water was designated as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0060]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] and the solution [C] were added at a constant speed of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] to obtain a white precipitate. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to an ammonia adding device (not shown), and the pH is controlled to 8.0 while adding ammonia from the injection nozzle 5 to perform a reaction. went. After completion of the addition, aging was performed for 45 minutes at a pH of 11.0 using ammonia to obtain a phosphor precursor 4. During aging, the signal from the sensor 6 was fed back to an ammonia addition device (not shown) to control the pH to 11.0 while appropriately adding ammonia. Thereafter, the phosphor precursor 4 was filtered and dried to obtain a dried phosphor precursor 4. Further, the dried phosphor precursor 4 was calcined at 1,400 ° C. under oxidizing conditions for 2 hours to obtain phosphor 4.
[0061]
<Manufacture of phosphor 5>
Phosphor 5 was obtained in the same manner as in the method for producing Phosphor 2, except that a solution [A] was prepared by dissolving 30 g (average molecular weight: about 100,000) of low-molecular gelatin in 1,000 ml of water.
[0062]
<Production of phosphor 6>
Phosphor 6 was obtained in the same manner as in the method of producing Phosphor 3, except that a solution obtained by dissolving 30 g of low-molecular gelatin (average molecular weight: about 100,000) in 1,000 ml of water was used as solution [A].
[0063]
<Production of phosphor 7>
Phosphor 7 was obtained in the same manner as in the method of producing Phosphor 4, except that a solution [A] was prepared by dissolving 30 g of low-molecular gelatin (average molecular weight: about 100,000) in 1,000 ml of water.
[0064]
The compositions of the obtained phosphors 1 to 7 were confirmed by a powder X-ray diffractometer, and as a result, (Y, Gd) BO₃: Eu³⁺Met. The phosphors (phosphors 1 to 7) were irradiated with vacuum ultraviolet rays (146 nm), and the emission intensity of each was determined. Next, the relative luminous intensity of each phosphor when the phosphor 1 was taken as 100% was calculated. Further, a photograph of the particles was taken with an electron microscope to calculate the average particle size and the coefficient of variation. Table 1 shows the results.
[0065]
[Table 1]

[0066]
As is clear from Table 1, the use of the production method of the present invention makes it possible to obtain a phosphor having a small particle size, a monodispersion and a high emission intensity.
[0067]
(Example 2)
<Production of phosphor 8>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0068]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] is added at a constant speed of 80 ml / min and the solution [C] is added at a constant speed of 20 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A]. Was. After the addition, aging was performed for 120 minutes to obtain a phosphor precursor 8. Thereafter, the phosphor precursor 8 was filtered and dried to obtain a dried phosphor precursor 8. Further, the dried phosphor precursor 8 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 8.
[0069]
<Production of phosphor 9>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0070]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] is added at a constant speed of 80 ml / min and the solution [C] is added at a constant speed of 20 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A]. Was. After the addition, the mixture was aged for 120 minutes to obtain a phosphor precursor 9. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to a nitric acid addition device (not shown), and the reaction is controlled by controlling the pH to 6.5 while adding nitric acid from the injection nozzle 5. went. After completion of the addition, aging was performed for 120 minutes to obtain a phosphor precursor 9. Thereafter, the phosphor precursor 9 was filtered and dried to obtain a dried phosphor precursor 9. Further, the dried phosphor precursor 9 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 9.
[0071]
<Production of phosphor 10>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0072]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] is added at a constant speed of 80 ml / min and the solution [C] is added at a constant speed of 20 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A]. Was. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to an ammonia adding device (not shown), and the pH is controlled to 11.0 while adding ammonia from the injection nozzle 5 to carry out the reaction. went. After completion of the addition, aging was performed for 120 minutes to obtain a phosphor precursor 10. Thereafter, the phosphor precursor 10 was filtered and dried to obtain a dried phosphor precursor 10. Further, the dried phosphor precursor 10 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain a phosphor 10.
[0073]
<Production of phosphor 11>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0074]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] is added at a constant speed of 80 ml / min and the solution [C] is added at a constant speed of 20 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A]. Was. At this time, a signal from the sensor 6 (in this case, a pH sensor is used) is fed back to an ammonia adding device (not shown), and the pH is controlled to 11.0 while adding ammonia from the injection nozzle 5 to carry out the reaction. went. After completion of the addition, aging was performed for 120 minutes by adjusting the pH to 13.0 with ammonia to obtain a phosphor precursor 11. During aging, the signal from the sensor 6 was fed back to an ammonia addition device (not shown) to control the pH to 13.0 while appropriately adding ammonia from the injection nozzle 5. Thereafter, the phosphor precursor 11 was filtered and dried to obtain a dried phosphor precursor 11. Further, the dried phosphor precursor 11 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 11.
[0075]
<Production of phosphor 12>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the method for producing phosphor 9, and Body 12 was obtained.
[0076]
<Production of phosphor 13>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the method for producing phosphor 10, and Body 13 was obtained.
[0077]
<Production of phosphor 14>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the production method of phosphor 11, and Obtained body 14.
[0078]
The compositions of the obtained phosphors 8 to 14 were confirmed by a powder X-ray diffractometer.₂SiO₄: Mn²⁺Met. The phosphors (phosphors 8 to 14) were irradiated with vacuum ultraviolet rays (146 nm), and the emission intensities of the respective phosphors were determined. Next, the relative emission intensity of each phosphor when the phosphor 8 was set to 100% was calculated. Further, a photograph of the particles was taken with an electron microscope to calculate the average particle size and the coefficient of variation. Table 2 shows the results.
[0079]
[Table 2]

[0080]
As is clear from Table 2, the use of the production method of the present invention makes it possible to obtain a phosphor having a small particle size, a monodispersion and a high emission intensity.
[0081]
(Example 3)
<Production of phosphor 15>
1,000 ml of water was used as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0082]
The solution [A] was placed in the container 1 of FIG. 1 and the temperature was maintained at 15 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] and the solution [C], which were also kept at 15 ° C., were added at a constant rate of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a constant speed, and a white precipitate was formed. Got. At this time, a signal from the sensor 6 (in this case, a temperature sensor was used) was fed back to a temperature controller (not shown), and the reaction was performed while controlling the temperature to 15 ° C. After completion of the addition, the mixture was aged for 45 minutes to obtain a phosphor precursor 15. Thereafter, the phosphor precursor 15 was filtered and dried to obtain a dried phosphor precursor 15. Further, the dried phosphor precursor 15 was baked at 1,400 ° C. under oxidizing conditions for 2 hours to obtain phosphor 15.
[0083]
<Production of phosphor 16>
1,000 ml of water was used as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0084]
The solution [A] was placed in the container 1 of FIG. 1 and the temperature was maintained at 45 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] and the solution [C] which were also kept at 45 ° C. were added at a constant rate of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a constant speed, and a white precipitate was formed. Got. At this time, a signal from the sensor 6 (in this case, a temperature sensor was used) was fed back to a temperature controller (not shown), and the reaction was performed while controlling the temperature at 45 ° C. After completion of the addition, the mixture was aged for 45 minutes to obtain a phosphor precursor 16. Thereafter, the phosphor precursor 16 was filtered and dried to obtain a dried phosphor precursor 16. Further, the dried phosphor precursor 16 was baked under an oxidation condition of 1,400 ° C. for 2 hours to obtain a phosphor 16.
[0085]
<Production of phosphor 17>
1,000 ml of water was used as solution [A]. Yttrium nitrate hexahydrate, gadolinium nitrate, nitric acid so that the ion concentration of yttrium is 0.4659 mol / l, the ion concentration of gadolinium is 0.2716 mol / l, and the ion concentration of europium is 0.0388 mol / l in 500 ml of water. Europium hexahydrate was dissolved to obtain a solution [B]. Boric acid was dissolved in 500 ml of water such that the ion concentration of boron was 0.7763 mol / l to obtain a solution [C].
[0086]
The solution [A] was placed in the container 1 of FIG. 1 and the temperature was maintained at 45 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] and the solution [C] which were also kept at 45 ° C. were added at a constant rate of 100 ml / min from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a constant speed, and a white precipitate was formed. Got. At this time, a signal from the sensor 6 (in this case, a temperature sensor was used) was fed back to a temperature controller (not shown), and the reaction was performed while controlling the temperature at 45 ° C. After completion of the addition, the mixture was heated to 80 ° C. and aged for 45 minutes to obtain a phosphor precursor 17. During aging, the signal from the sensor 6 was fed back to a temperature controller (not shown) to control the temperature to 80 ° C. Thereafter, the phosphor precursor 17 was filtered and dried to obtain a dried phosphor precursor 17. Further, the dried phosphor precursor 17 was baked under an oxidation condition of 1,400 ° C. for 2 hours to obtain phosphor 17.
[0087]
<Production of phosphor 18>
Phosphor 18 was obtained in the same manner as in the method of producing Phosphor 15, except that 30 g of low-molecular gelatin (average molecular weight: about 100,000) was dissolved in 1,000 ml of water to prepare solution [A].
[0088]
<Production of phosphor 19>
Phosphor 19 was obtained in the same manner as in the method of producing Phosphor 16, except that 30 g of low-molecular gelatin (average molecular weight: about 100,000) was dissolved in 1,000 ml of water to prepare solution [A].
[0089]
<Manufacture of phosphor 20>
Phosphor 20 was obtained in the same manner as in the method for producing phosphor 17, except that 30 g of low-molecular gelatin (average molecular weight: about 100,000) was dissolved in 1,000 ml of water to prepare solution [A].
[0090]
The composition of the obtained phosphors 15 to 20 was confirmed by a powder X-ray diffractometer, and as a result, (Y, Gd) BO₃: Eu³⁺Met. The phosphors (phosphors 15 to 20) were irradiated with vacuum ultraviolet rays (146 nm), and the emission intensities of the respective phosphors were determined. Next, the relative luminous intensity of each phosphor when the phosphor 1 produced in Example 1 was taken as 100% was calculated. Further, a photograph of the particles was taken with an electron microscope to calculate the average particle size and the coefficient of variation. Table 3 shows the results.
[0091]
[Table 3]

[0092]
As is clear from Table 3, the use of the production method of the present invention makes it possible to obtain a phosphor having a small particle size, a monodispersion and a high emission intensity.
[0093]
(Example 4)
<Manufacture of phosphor 21>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0094]
The solution [A] was placed in the container 1 of FIG. 1 and the temperature was kept at 25 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] also kept at 25 ° C. from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a rate of 80 ml / min. Was added at a constant speed of 20 ml / min. After the addition, aging was performed for 120 minutes to obtain a phosphor precursor 21. Thereafter, the phosphor precursor 21 was filtered and dried to obtain a dried phosphor precursor 21. Further, the dried phosphor precursor 21 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 21.
[0095]
<Production of phosphor 22>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0096]
The solution [A] was put in the container 1 of FIG. 1, and the temperature was kept at 55 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] also kept at 55 ° C. from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a rate of 80 ml / min. Was added at a constant speed of 20 ml / min. After the addition, the mixture was aged for 120 minutes to obtain a phosphor precursor 22. At this time, a signal from the sensor 6 (in this case, a temperature sensor was used) was fed back to a temperature controller (not shown), and the reaction was performed while controlling the temperature to 55 ° C. After completion of the addition, aging was performed for 120 minutes to obtain a phosphor precursor 22. Thereafter, the phosphor precursor 22 was filtered and dried to obtain a dried phosphor precursor 22. Further, the dried phosphor precursor 22 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain a phosphor 22.
[0097]
<Production of phosphor 23>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0098]
The solution [A] was put in the container 1 of FIG. 1, and the temperature was kept at 55 ° C., and stirring was performed using the stirring mechanism 2. In this state, the solution [B] also kept at 55 ° C. from the pouring nozzles 3 and 4 of the container 1 containing the solution [A] at a rate of 80 ml / min. Was added at a constant speed of 20 ml / min. At this time, a signal from the sensor 6 (in this case, a temperature sensor was used) was fed back to a temperature controller (not shown), and the reaction was performed while controlling the temperature to 55 ° C. After completion of the addition, the mixture was heated to 80 ° C. and aged for 120 minutes to obtain a phosphor precursor 23. During aging, the signal from the temperature sensor 6 was fed back to a temperature controller (not shown) to control the temperature to 80 ° C. Thereafter, the phosphor precursor 23 was filtered and dried to obtain a dried phosphor precursor 23. Further, the dried phosphor precursor 23 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 23.
[0099]
<Manufacture of phosphor 24>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the method for producing phosphor 21. Body 24 was obtained.
[0100]
<Manufacture of phosphor 25>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the method of manufacturing phosphor 22. A body 25 was obtained.
[0101]
<Production of phosphor 26>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the production method of phosphor 23, A body 26 was obtained.
[0102]
The composition of the obtained phosphors 21 to 26 was confirmed by a powder X-ray diffractometer.₂SiO₄: Mn²⁺Met. The phosphors (phosphors 21 to 26) were irradiated with vacuum ultraviolet rays (146 nm), and the emission intensities of the respective phosphors were determined. Next, the relative luminous intensity of each phosphor when the phosphor 8 produced in Example 2 was taken as 100% was calculated. Further, a photograph of the particles was taken with an electron microscope to calculate the average particle size and the coefficient of variation. Table 4 shows the results.
[0103]
[Table 4]

[0104]
As is clear from Table 4, the use of the production method of the present invention makes it possible to obtain a phosphor having a small particle size, a monodispersion and a high emission intensity.
[0105]
(Example 5)
<Production of phosphor 27>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0106]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] was added from the pouring nozzle 3 of the container containing the solution [A]. At this time, a signal from the sensor 6 (in this case, a zinc ion concentration sensor was used) is fed back to a zinc chloride adding device (not shown) to reduce the zinc ion concentration to 2.2 × 10 2^-1The reaction was performed while controlling to be mol / l. The solution [C] was added at a constant speed of 20 ml / min from the injection nozzle 4. After completion of the addition, aging was performed for 120 minutes to obtain a phosphor precursor 27. Thereafter, the phosphor precursor 27 was filtered and dried to obtain a dried phosphor precursor 27. Further, the dried phosphor precursor 27 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 27.
[0107]
<Production of phosphor 28>
The zinc ion concentration is 4.8 × 10^-2Phosphor 28 was obtained in the same manner as in the method for producing phosphor 27, except that the reaction was carried out while controlling to be mol / l.
[0108]
<Production of phosphor 29>
Sodium metasilicate was dissolved in 800 ml of water such that the ion concentration of silicon was 0.4655 mol / l, to obtain a solution [A]. Zinc chloride was dissolved in 800 ml of water such that the ion concentration of zinc was 0.8845 mol / l to obtain a solution [B]. Manganese chloride tetrahydrate was dissolved in 200 ml of water such that the manganese ion concentration was 0.1862 mol / l, to obtain a solution [C].
[0109]
The solution [A] was placed in the container 1 of FIG. 1 and stirred using the stirring mechanism 2. In this state, the solution [B] was added from the pouring nozzle 3 of the container containing the solution [A]. At this time, a signal from the sensor 6 (in this case, a zinc ion concentration sensor was used) is fed back to a zinc chloride adding device (not shown) so that the zinc ion concentration is 4.8 × 10^-2The reaction was performed while controlling to be mol / l. The solution [C] was added at a constant speed of 20 ml / min from the pouring nozzle 4. After the addition is completed, the zinc ion concentration is reduced to 1 × 10^-5The mixture was changed to mol / l and aged for 120 minutes to obtain a phosphor precursor 29. At the time of ripening, the signal from the sensor 6 is fed back to a zinc chloride adding device (not shown) to obtain 6.7 × 10^-4mol / l. Thereafter, the phosphor precursor 29 was filtered and dried to obtain a dried phosphor precursor 29. Further, the dried phosphor precursor 29 was fired at 1,050 ° C. in a nitrogen atmosphere for 3 hours to obtain phosphor 29.
[0110]
<Manufacture of phosphor 30>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the method of manufacturing phosphor 27. The body 30 was obtained.
[0111]
<Production of phosphor 31>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the production method of phosphor 28, Body 31 was obtained.
[0112]
<Production of phosphor 32>
Except that low-molecular-weight gelatin (average molecular weight: about 100,000) was added and dissolved in solution [A], solution [B], and solution [C] by 3% by mass, respectively, in the same manner as in the production method of phosphor 29, Body 32 was obtained.
[0113]
The composition of the obtained phosphors 27 to 32 was confirmed by a powder X-ray diffractometer.₂SiO₄: Mn²⁺Met. The phosphors (phosphors 27 to 32) were irradiated with vacuum ultraviolet rays (146 nm), and the emission intensities of the respective phosphors were determined. Next, the relative luminous intensity of each phosphor when the phosphor 8 produced in Example 2 was taken as 100% was calculated. Further, a photograph of the particles was taken with an electron microscope to calculate the average particle size and the coefficient of variation. Table 5 shows the results.
[0114]
[Table 5]

[0115]
As is clear from Table 5, the use of the production method of the present invention makes it possible to obtain a phosphor having a small particle size, a monodispersion and a high emission intensity.
[0116]
【The invention's effect】
A method for producing a phosphor having a small particle size, a narrow particle size distribution, and good emission intensity can be provided.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing an example of a phosphor precursor generating apparatus according to the present invention.
[Explanation of symbols]
1 container
2 stirring mechanism
3, 4, 5 pouring nozzle
6 sensor

Claims

In a method for producing a phosphor, in which a phosphor is obtained by calcining the phosphor precursor after producing the phosphor precursor in the liquid phase, at least one time from the start to the end of the production of the phosphor precursor is obtained. A method for producing a phosphor, comprising producing a phosphor precursor while controlling the pH of a part.

The method according to claim 1, wherein the pH control is performed in a range of pH 7 to pH 14.

3. The method for producing a phosphor according to claim 1, wherein the pH control is performed twice or more.

In a method for producing a phosphor, in which a phosphor is obtained by calcining the phosphor precursor after producing the phosphor precursor in a liquid phase, at least one time from the start to the end of the production of the phosphor precursor is obtained. A method for producing a phosphor, comprising: producing a phosphor precursor while controlling the temperature of a part.

The method according to claim 4, wherein the temperature control is performed in a range of 30C to 70C.

The method according to claim 4, wherein the temperature control is performed twice or more.

In a method for producing a phosphor, in which a phosphor is obtained by calcining the phosphor precursor after producing the phosphor precursor in a liquid phase, at least one time from the start to the end of the production of the phosphor precursor is obtained. A method for producing a phosphor, characterized in that the phosphor precursor is produced while controlling the ion concentration of at least one of the constituent elements of the phosphor precursor.

The method according to claim 7, wherein the ion concentration control is performed twice or more.

The method for producing a phosphor according to any one of claims 1 to 8, wherein the phosphor precursor is generated in the presence of a binder.

What is claimed is: 1. A phosphor precursor generating apparatus for producing a phosphor precursor by a liquid phase method, wherein a pH sensor is provided in a reaction vessel for producing the phosphor precursor. apparatus.

What is claimed is: 1. A phosphor precursor generating apparatus for producing a phosphor precursor by a liquid phase method, wherein a temperature sensor is provided in a reaction vessel for producing the phosphor precursor. apparatus.

What is claimed is: 1. A phosphor precursor generating apparatus for producing a phosphor precursor by a liquid phase method, wherein at least two types of sensors are provided in a reaction vessel for producing said phosphor precursor. Precursor generator.

13. The phosphor precursor generating apparatus according to claim 12, wherein the sensors are at least two types selected from a temperature sensor, a pH sensor, and a metal ion concentration sensor.