JP2004063239A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel improving emission efficiency of a phosphor and having high luminance even if definition is higher. <P>SOLUTION: The plasma display panel 1 comprises a front surface side substrate 10 having an information display surface 10b, a back surface side substrate 20, a barrier rib 30 disposed between the substrates 10, 20, a discharge cell 31 formed surrounded by the barrier rib 30 and the substrates 10, 20, and a phosphor layer 35. The sum of the surface area of the phosphor particles forming the phosphor layer 35 is between 100mm<SP>2</SP>/mm<SP>2</SP>and 3,000mm<SP>2</SP>/mm<SP>2</SP>per unit area of the information display surface 10b. <P>COPYRIGHT: (C)2004,JPO

Description

【０１４５】
表１から明らかなように、比較例１の相対輝度を１００としたときの、ＰＤＰ１−１の相対輝度は１３６、ＰＤＰ１−２の相対輝度は１８６と比較例１に対して本発明のＰＤＰは極めて高い相対輝度値を得ることができた。
【０１４６】
ＰＤＰ１−１、ＰＤＰ１−２及び比較例のＰＤＰのいずれについても、最小発光単位あたりの蛍光体ペーストの量は平均０．０６３５ｍｇと等しく、蛍光体層中に含有する蛍光体の質量は０．０２５４ｍｇと等しい。このように、最小発光単位あたりの蛍光体付量は等しいのにも関わらず、相対輝度が著しく異なるのは、表１からも明らかなように、使用した蛍光体の平均粒径が異なり、それにより情報表示面１０ｂの１ｍｍ^２あたりの蛍光体粒子の表面積の総和が大きく異なるためである。
【０１４７】
比較例１では、固相合成法で製造された平均粒径が２．１０〜２．１６μｍの蛍光体を使用し、それにより、情報表示面１０ｂの１ｍｍ^２あたりの蛍光体粒子の表面積が８６〜８８ｍｍ^２である。これに対して、ＰＤＰ１−１は、液相合成法で製造された平均粒径が０．７７〜０．８２μｍの蛍光体を使用し、それにより、情報表示面１０ｂの１ｍｍ^２あたりの蛍光体粒子の表面積が２２６〜２４０ｍｍ^２である。ＰＤＰ１−２は、同じく液相合成法で製造された平均粒径が０．３８〜０．３９μｍの蛍光体を使用し、それにより、情報表示面１０ｂの１ｍｍ^２あたりの表面積が４７５〜４８７ｍｍ^２である。
このように、蛍光体層３５を構成する蛍光体を微粒化して、その表面積を増大することによって、蛍光体付量が等しい場合でも、紫外線を効率よく受光して、発光量を増大し、ＰＤＰの相対輝度を向上させることができる。
【０１４８】
〔実施例２〕
次に、実施例２について説明する。本実施例２では、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数を１０００万個／ｍｍ^２以上としたＰＤＰ２−１と、８０００万個／ｍｍ^２以上としたＰＤＰ２−２とを製造した。これらと比較するために、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数を７００万個／ｍｍ^２未満とした比較例２を製造した。
まず、蛍光体の製造について説明する。
【０１４９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−４の製造
実施例１の１（１）において、Ｂ液とＣ液のＡ液への添加速度を５．１０ｃｃ／ｍｉｎとした以外は、実施例１の１（１）と同様にして青色発光蛍光体Ｂ−４を製造した。
焼成後、得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７８μｍであった。
【０１５０】
（２）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−５の製造
実施例１の１（２）において、Ｂ液とＣ液のＡ液への添加速度を９．９ｃｃ／ｍｉｎにした以外は、実施例１の１（２）と同様にして青色発光蛍光体Ｂ−５を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．４１μｍであった。
【０１５１】
（３）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−４の製造
上記実施例１の１（３）において、Ｂ液とＣ液のＡ液への添加速度を９．７２ｃｃ／ｍｉｎとした以外は、実施例１の１（３）と同様にして緑色発光蛍光体Ｇ−４を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７７μｍであった。
【０１５２】
（４）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−５の製造
上記実施例１の１（４）において、Ｂ液とＣ液のＡ液への添加速度を９．７２ｃｃ／ｍｉｎとした以外は、実施例１の１（４）と同様に、コロイダルシリカを用いて緑色発光蛍光体Ｇ−６を製造した。
得られた蛍光体Ｂ−６の平均粒径を顕微鏡観察により求めたところ、０．３９μｍであった。
【０１５３】
（５）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−４の製造
上記実施例１の１（５）において、Ｂ液とＣ液のＡ液への添加速度を１０．３ｃｃ／ｍｉｎとした以外は、実施例１の１（５）と同様にして赤色発光蛍光体Ｒ−４を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７６μｍであった。
【０１５４】
（６）赤色蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−５の製造
上記実施例１の１（６）において、Ｂ液とＣ液のＡ液への添加速度を２９．８ｃｃ／ｍｉｎとした以外は、実施例１の１（６）と同様にして赤色発光蛍光体Ｒ−５を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．４０μｍであった。
【０１５５】
２．蛍光体ペーストの調整
上記で製造した青色発光蛍光体Ｂ−４、Ｂ−５、Ｇ−４、Ｇ−５、Ｒ−４、Ｒ−５を用いて、実施例１の２と同様の方法で、青色発光蛍光体ペーストＢ−４、Ｂ−５、緑色発光蛍光体ペーストＧ−４、Ｇ−５、赤色発光蛍光体ペーストＲ−４、Ｒ−５をそれぞれ調整した。
【０１５６】
３．ＰＤＰの製造
（１）ＰＤＰ２−１の製造
上記で調整した青色発光蛍光体ペーストＢ−４，緑色発光蛍光体ペーストＧ−４、赤色発光蛍光体ペーストＲ−４を用いた以外は、実施例１の３（１）と同様な方法でＰＤＰ２−１を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−４、Ｒ−４、Ｇ−４は実施例１の３（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇ（含蛍光体量０．０２５４ｍｇ）である。
このとき、青色発光蛍光体Ｂ−４の情報表示面１０ｂの単位面積あたりの蛍光体の個数は、１２４×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−４については、１２９×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−４については１３４×１０^６個／ｍｍ^２となった。
【０１５７】
（２）ＰＤＰ２−２の製造
上記で調整した青色発光蛍光体ペーストＢ−５，緑色発光蛍光体ペーストＧ−５、赤色発光蛍光体ペーストＲ−５を用いた以外は、実施例１の３（１）と同様な方法でＰＤＰ２−２を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−５、Ｒ−５、Ｇ−５は実施例１の３（１）と同様に一つの最小発光単位あたりについて平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−５の情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数は、８５４×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−５については、９９３×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−５については９２０×１０^６個／ｍｍ^２となった。
【０１５８】
〔比較例２〕
上記の実施例２で製造したＰＤＰ２−１、２−２と比較するために、固相合成法により蛍光体を製造して、得られた蛍光体を用いて情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数が７×１０^６個／ｍｍ^２以下となるようにＰＤＰを製造した。
まず、各色の蛍光体の製造方法について説明する。
【０１５９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−６の製造
比較例１の１（１）と同様にして蛍光体を製造し、平均粒径２．１７μｍのものを分級して青色発光蛍光体Ｂ−６とした。
【０１６０】
（２）緑色発光蛍光体（ＺｎＳｉＯ_４：Ｍｎ）Ｇ−６の製造
比較例１の１（２）と同様にして蛍光体を製造し、平均粒径２．１７μｍのものを分級して緑色発光蛍光体Ｂ−６とした。
【０１６１】
（３）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−６の製造
比較例１の１（３）と同様にして蛍光体を製造し、平均粒径２．０８μｍのものを分級して赤色発光蛍光体Ｒ−６とした。
【０１６２】
２．蛍光体ペーストの調整
上記で得た蛍光体Ｂ−６、Ｇ−６、Ｒ−６を用いた以外は、実施例１の２と同様に各色発光蛍光体ペーストＢ−６、Ｇ−６、Ｒ−６をそれぞれ調整した。
【０１６３】
３．ＰＤＰの製造
上記の２で調整した青色発光蛍光体ペーストＢ−６，緑色発光蛍光体ペーストＧ−６、赤色発光蛍光体ペーストＲ−６を用いた以外は、実施例１の３（１）と同様にＰＤＰを製造した。なお、塗布の際に用いた蛍光体ペーストＢ−６、Ｒ−６、Ｇ−６は実施例１の３（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−６の情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数は５．７×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−６については、５．７×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−６については６．５×１０^６個／ｍｍ^２となった。これを比較例２のＰＤＰとした。
【０１６４】
〔評価２〕
上記で製造したＰＤＰ２−１、ＰＤＰ２−２と比較例２について、情報表示面１０ｂの単位面積当たりの蛍光体粒子の個数（個／ｍｍ^２）と、ＰＤＰの相対輝度について、評価１と同様な方法で評価した。結果を表２に示す。
【表２】

【０１６５】
表２から明らかなように、比較例２の相対輝度を１００としたときの、ＰＤＰ２−１の相対輝度は１３２、ＰＤＰ２−２の相対輝度は１７６と比較例２に対して本発明のＰＤＰは極めて高い相対輝度値を得ることができた。
【０１６６】
ＰＤＰ２−１、ＰＤＰ２−２及び比較例２のＰＤＰのいずれについても、最小発光単位あたりの蛍光体ペーストの量は平均０．０６３５ｍｇと等しく、蛍光体層３５中に含有する蛍光体の質量は０．０２５４ｍｇと等しい。このように、最小発光単位あたりの蛍光体付量は等しいのにも関わらず、相対輝度が著しくことなるのは、表２からも明らかなように、使用した蛍光体の平均粒径が異なり、それにより、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数が大きく異なるためである。
【０１６７】
比較例２は、固相合成法で製造された平均粒径が２．０８〜２．１７μｍの蛍光体を使用し、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数は、５．７×１０^６〜６．５×１０^６個／ｍｍ^２である。
これに対して、ＰＤＰ２−１は、液相合成法で製造された平均粒径が０．７６〜０．７８μｍの蛍光体を使用し、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数は１２４×１０^６〜１３４×１０^６個／ｍｍ^２、ＰＤＰ２−２は、平均粒径が０．３９〜０．４１μｍの蛍光体粒子を使用し、情報表示面１０ｂの単位面積あたりの蛍光体粒子の個数は、８５４×１０^６〜９９３×１０^６個／ｍｍ^２である。
このように、蛍光体層３５を構成する蛍光体粒子を微粒化して個数を増加することによって、紫外線を効率よく受光して、発光量を増大し、それによりＰＤＰの相対輝度を著しく向上させることができる。
【０１６８】
〔実施例３〕
次に、実施例３について説明する。本実施例３では、放電セル３１内の蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の表面積の総和が異なる２つのＰＤＰを製造した。一つ目のＰＤＰ３−１は、蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和を８０ｍｍ^２以上とした。二つ目のＰＤＰ３−２は、同蛍光体粒子の表面積の総和を１５０ｍｍ^２以上とした。これらと比較するために、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の表面積の総和を４０ｍｍ^２未満としたＰＤＰを製造して比較例３とした。
まず、蛍光体の製造について説明する。
【０１６９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−７の製造
実施例１の１（１）において、Ｂ液とＣ液のＡ液への添加速度を５．０５ｃｃ／ｍｉｎとした以外は、実施例１の１（１）と同様にして青色発光蛍光体Ｂ−７を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７６μｍであった。
【０１７０】
（２）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−８の製造
実施例１の１（２）において、Ｂ液とＣ液のＡ液への添加速度を１０．５ｃｃ／ｍｉｎとした以外は、実施例１の１（２）と同様にして青色発光蛍光体Ｂ−８を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．４１μｍであった。
【０１７１】
（３）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−７の製造
実施例１の１（３）において、Ｂ液とＣ液のＡ液への添加速度を１０．１ｃｃ／ｍｉｎとした以外は実施例１の１（３）と同様にして緑色発光蛍光体Ｇ−７を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７７μｍであった。
【０１７２】
（４）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−８の製造
上記実施例１の１（４）において、Ｂ液とＣ液のＡ液への添加速度を１０．１ｃｃ／ｍｉｎとした以外は実施例１の１（４）と同様にコロイダルシリカを用いて緑色発光蛍光体Ｇ−８を製造した。
得られた蛍光体Ｇ−８の平均粒径を顕微鏡観察により求めたところ、０．３８μｍであった。
【０１７３】
（５）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−７の製造
上記の実施例１の１（５）において、Ｂ液とＣ液のＡ液への添加速度を１０．３ｃｃ／ｍｉｎとした以外は、実施例１の１（５）と同様にして赤色発光蛍光体Ｒ−７を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７６μｍであった。
【０１７４】
（６）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−８の製造
上記の実施例１の１（６）において、Ｂ液とＣ液のＡ液への添加速度を２９．９ｃｃ／ｍｉｎにした以外は、実施例１の１（６）と同様にして赤色発光蛍光体Ｒ−８を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．４２μｍであった。
【０１７５】
２．蛍光体ペーストの調整
上記１で製造した青色発光蛍光体Ｂ−７、Ｂ−８、Ｇ−７、Ｇ−８、Ｒ−７、Ｒ−８を用いて、実施例１の２と同様の方法で、青色発光蛍光体ペーストＢ−７、Ｂ−８、緑色発光蛍光体ペーストＧ−７、Ｇ−８、赤色発光蛍光体ペーストＲ−７、Ｒ−８をそれぞれ調整した。
【０１７６】
３．ＰＤＰの製造
（１）ＰＤＰ３−１の製造
上記で調整した青色発光蛍光体ペーストＢ−７，緑色発光蛍光体ペーストＧ−７、赤色発光蛍光体ペーストＲ−７を用いた以外は、実施例１の３（１）と同様な方法でＰＤＰ３−１を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−７、Ｒ−７、Ｇ−７は実施例１の３（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇ（含蛍光体量０．０２５４ｍｇ）である。
このとき、青色発光蛍光体Ｂ−７の蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和は、８８ｍｍ^２となった。また、緑色発光蛍光体Ｇ−７については、８７ｍｍ^２、赤色発光蛍光体Ｒ−７については８８ｍｍ^２となった。
【０１７７】
（２）ＰＤＰ３−２の製造
上記で調整した青色発光蛍光体ペーストＢ−８，緑色発光蛍光体ペーストＧ−８、赤色発光蛍光体ペーストＲ−８を用いた以外は、実施例１の３の（１）と同様な方法でＰＤＰ３−２を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−８、Ｒ−８、Ｇ−８は実施例１の３の（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−８の蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和は、１８５ｍｍ^２となった。また、緑色発光蛍光体Ｇ−８については、１７６ｍｍ^２、赤色発光蛍光体Ｒ−８については１５９ｍｍ^２となった。
【０１７８】
〔比較例３〕
上記のＰＤＰ３−１、ＰＤＰ３−２と比較するために、固相合成法により蛍光体を製造して、得られた蛍光体を用いて蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和が４０ｍｍ^２以下となるようにＰＤＰを製造した。
まず、各色の蛍光体の製造方法について説明する。
【０１７９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−９の製造
比較例１の１（１）と同様にして蛍光体を製造し、平均粒径２．１２μｍのものを分級して青色発光蛍光体Ｂ−９とした。
【０１８０】
（２）緑色発光蛍光体（ＺｎＳｉＯ_４：Ｍｎ）Ｇ−９の製造
比較例１の１（２）と同様にして蛍光体を製造し、平均粒径２．１０μｍのものを分級して緑色発光蛍光体Ｇ−９とした。
【０１８１】
（３）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）の製造
比較例１の１（３）と同様にして蛍光体を製造し、平均粒径２．０８μｍのものを分級して赤色発光蛍光体Ｒ−９とした。
【０１８２】
２．蛍光体ペーストの調整
上記で得た各色発光蛍光体Ｂ−９、Ｇ−９、Ｒ−９を用いた以外は、実施例１の２と同様に各色発光蛍光体ペーストＢ−９、Ｇ−９、Ｒ−９をそれぞれ調整した。
【０１８３】
３．ＰＤＰの製造
上記の２で調整した青色発光蛍光体ペーストＢ−９，緑色発光蛍光体ペーストＧ−９、赤色発光蛍光体ペーストＲ−９を用いた以外は、実施例１の３（１）と同様にＰＤＰを製造した。なお、塗布の際に用いた蛍光体ペーストＢ−９、Ｒ−９、Ｇ−９は実施例１の３の（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−９の蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和は、３１ｍｍ^２となった。また、緑色発光蛍光体Ｇ−９については、３２ｍｍ^２、赤色発光蛍光体Ｒ−９については３２ｍｍ^２となった。これを比較例３のＰＤＰとした。
【０１８４】
〔評価３〕
上記で製造したＰＤＰ３−１、ＰＤＰ３−２と比較例３について、蛍光体層被覆可能面１ｍｍ^２あたりの蛍光体粒子の表面積の総和（ｍｍ^２）と、ＰＤＰの相対輝度について評価１と同様な方法で評価した。結果を表３に示す。
【表３】

【０１８５】
表３から明らかなように、比較例３の相対輝度を１００としたときの、ＰＤＰ３−１の相対輝度は１４１、ＰＤＰ３−２の相対輝度は１９５と比較例３に対して本発明のＰＤＰは極めて高い相対輝度値を得ることができた。
【０１８６】
ＰＤＰ３−１、ＰＤＰ３−２及び比較例３のＰＤＰのいずれについても、最小発光単位あたりの蛍光体ペーストの量は平均０．０６３５ｍｇと等しく、蛍光体層３５中の蛍光体付量は０．０２５４ｍｇと等しい。このように、最小発光単位あたりの蛍光体付量は等しいのにも関わらず、相対輝度が著しく異なるのは、表３からも明らかなように、使用した蛍光体の平均粒径が異なり、それにより蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和が大きく異なるためである。
【０１８７】
比較例３では、固相合成法により製造された平均粒径が２．０８〜２．１２μｍの蛍光体を使用し、それにより蛍光体層被覆可能面の１ｍｍ^２あたりの蛍光体粒子の表面積の総和が３１〜３２ｍｍ^２である。これに対して、ＰＤＰ３−１は、液相合成法により製造された平均粒径が０．７６〜０．７７μｍの蛍光体を使用し、それにより表面積の総和が８７〜８８ｍｍ^２である。ＰＤＰ３−２は、同じく液相合成法により製造された平均粒径が０．３６〜０．４２μｍの蛍光体を使用し、それにより表面積の総和が１５９〜１８５ｍｍ^２である。このように、蛍光体付量が等しい場合でも、微粒の蛍光体を使用し、それにより、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の表面積の総和を増大することによって、効率よく紫外線を受光して、相対輝度を著しく向上することができる。
【０１８８】
〔実施例４〕
次に、実施例４について説明する。本実施例４では、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数を３０万個／ｍｍ^２以上としたＰＤＰ４−１と、３００万個／ｍｍ^２以上としたＰＤＰ４−２とを製造した。これらと比較するために、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数を３万個／ｍｍ^２未満とした比較例４を製造した。
まず、蛍光体の製造について説明する。
【０１８９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−１０の製造
上記実施例１の１（１）において、Ｂ液とＣ液のＡ液への添加速度を４．９０ｃｃ／ｍｉｎとした以外は、実施例１の１（１）と同様に製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．８５μｍであった。
【０１９０】
（２）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−１１の製造
上記実施例１の１（２）において、Ｂ液とＣ液のＡ液への添加速度を１０．６ｃｃ／ｍｉｎとした以外は、実施例１の１（２）と同様にして青色発光蛍光体Ｂ−１１を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．３６μｍであった。
【０１９１】
（３）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−１０の製造
上記実施例１の１（３）において、Ｂ液とＣ液のＡ液への添加速度を９．５０ｃｃ／ｍｉｎとした以外は実施例１の１（３）と同様にして緑色発光蛍光体Ｇ−１０を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．８４μｍであった。
【０１９２】
（４）緑色発光蛍光体（Ｚｎ_２ＳｉＯ_４：Ｍｎ）Ｇ−１１の製造
上記実施例１の１（４）において、Ｂ液とＣ液のＡ液への添加速度を９．５０ｃｃ／ｍｉｎとした以外は実施例１の１（４）と同様にしてコロイダルシリカを用いて緑色発光蛍光体Ｇ−１１を製造した。
得られた蛍光体Ｇ−１１の平均粒径を顕微鏡観察により求めたところ、０．３９μｍであった。
【０１９３】
（５）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−１０の製造
上記実施例１の１（５）において、Ｂ液とＣ液のＡ液への添加速度を１０．７ｃｃ／ｍｉｎとした以外は、実施例１の１（５）と同様にして赤色発光蛍光体Ｒ−１０を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．７５μｍであった。
【０１９４】
（６）赤色蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−１１の製造
上記実施例１の１（６）において、Ｂ液とＣ液のＡ液への添加速度を２９．９ｃｃ／ｍｉｎとした以外は、実施例１の１（６）と同様にして赤色発光蛍光体Ｒ−１１を製造した。
得られた蛍光体の平均粒径を電子顕微鏡観察により求めたところ、０．４１μｍであった。
【０１９５】
２．蛍光体ペーストの調整
上記１で製造した青色発光蛍光体Ｂ−１０、Ｂ−１１、Ｇ−１０、Ｇ−１１、Ｒ−１０、Ｒ−１１を用いて、実施例１の２と同様の方法で、青色発光蛍光体ペーストＢ−１０、Ｂ−１１、緑色発光蛍光体ペーストＧ−１０、Ｇ−１１、赤色発光蛍光体ペーストＲ−１０、Ｒ−１０をそれぞれ調整した。
【０１９６】
３．ＰＤＰの製造
（１）ＰＤＰ４−１の製造
上記２で調整した青色発光蛍光体ペーストＢ−１０，緑色発光蛍光体ペーストＧ−１０、赤色発光蛍光体ペーストＲ−１０を用いた以外は、実施例１の３（１）と同様な方法でＰＤＰ４−１を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−１０、Ｒ−１０、Ｇ−１０は実施例１の３（１）と同様に一つの最小発光単位あたり平均０．０６３５ｍｇ（含蛍光体量０．０２５４ｍｇ）である。
このとき、青色発光蛍光体Ｂ−１０の蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数は、３４×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−１０については、３５×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−１０については５０×１０^６個／ｍｍ^２となった。
【０１９７】
（２）ＰＤＰ４−２の製造
上記で調整した青色発光蛍光体ペーストＢ−１１、緑色発光蛍光体ペーストＧ−１１、赤色発光蛍光体ペーストＲ−１１を用いた以外は、実施例１の３（１）と同様な方法でＰＤＰ４−２を製造した。なお、塗布の際に用いた蛍光体ペーストＢ−１１、Ｒ−１１、Ｇ−１１は実施例１の３（１）と同様に、一つの最小発光単位あたり平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−１１の蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数は、４５５×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−１１については、３５７×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−１１については３０８×１０^６個／ｍｍ^２となった。
【０１９８】
〔比較例４〕
上記の実施例４と比較するために、固相合成法により蛍光体を製造して、得られた蛍光体を用いて蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数が３×１０^６個／ｍｍ^２以下となるようにＰＤＰを製造した。
まず、各色の蛍光体の製造方法について説明する。
【０１９９】
１．蛍光体の製造
（１）青色発光蛍光体（ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ^２＋）Ｂ−１２の製造
比較例１の１（１）と同様にして蛍光体を製造し、平均粒径２．０５μｍの粒子を分級して青色発光蛍光体Ｂ−１２とした。
【０２００】
（２）緑色発光蛍光体（ＺｎＳｉＯ_４：Ｍｎ）Ｇ−１２の製造
比較例１の１（２）と同様にして蛍光体を製造し、平均粒径２．０７μｍの粒子を分級して緑色発光蛍光体Ｇ−１２とした。
【０２０１】
（３）赤色発光蛍光体（（Ｙ，Ｇｄ）ＢＯ_３：Ｅｕ^３＋）Ｒ−１２の製造
比較例１の１（３）と同様にして蛍光体を製造し、平均粒径２．１１μｍの粒子を分級して赤色発光蛍光体Ｒ−１２とした。
【０２０２】
２．蛍光体ペーストの調整
上記で得た蛍光体Ｂ−１２、Ｇ−１２、Ｒ−１２を用いた以外は、実施例１の２と同様に各色発光蛍光体ペーストＢ−１２、Ｇ−１２、Ｒ−１２をそれぞれ調整した。
【０２０３】
３．ＰＤＰの製造
上記の２で調整した青色発光蛍光体ペーストＢ−１２，緑色発光蛍光体ペーストＧ−１２、赤色発光蛍光体ペーストＲ−１２を用いた以外は、実施例１の３の（１）と同様にＰＤＰを製造した。なお、塗布の際に用いた蛍光体ペーストＢ−１２、Ｒ−１２、Ｇ−１２は実施例１の３（１）と同様に、一つの最小発光単位あたり平均０．０６３５ｍｇである。
このとき、青色発光蛍光体Ｂ−１２の蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数は２．４×１０^６個／ｍｍ^２となった。また、緑色発光蛍光体Ｇ−１２については、２．３×１０^６個／ｍｍ^２、赤色発光蛍光体Ｒ−１２については２．２×１０^６個／ｍｍ^２となった。これを比較例４のＰＤＰとした。
【０２０４】
〔評価４〕
上記で製造したＰＤＰ４−１、ＰＤＰ４−２と比較例４について、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数（個／ｍｍ^２）と、ＰＤＰの相対輝度について評価した。評価は上記の評価Ｉと同様にして行い、相対値により比較した。結果を表４に示す。
【表４】

【０２０５】
表４から明らかなように、比較例４の相対輝度を１００としたときの、ＰＤＰ４−１の相対輝度は１２７、ＰＤＰ４−２の相対輝度は１６７と比較例４に対して本発明のＰＤＰは極めて高い相対輝度値を得ることができた。
【０２０６】
ＰＤＰ４−１、ＰＤＰ４−２及び比較例４のＰＤＰのいずれについても、最小発光単位あたりの蛍光体ペーストの量は平均０．０６３５ｍｇと等しく、蛍光体層中に含有する蛍光体の質量は等しく、０．０２５４ｍｇである。このように、最小発光単位あたりの蛍光体付量は等しいのにも関わらず、相対輝度が著しく異なるのは、表４からも明らかなように、使用した蛍光体の平均粒径が異なり、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数が大きく異なるからである。
【０２０７】
比較例４では、固相合成法により製造された平均粒径が２．０５〜２．１１μｍの蛍光体を使用し、それにより蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数が２．２×１０^６〜２．４×１０^６個／ｍｍ^２である。
これに対して、ＰＤＰ４−１は、液相合成法により製造された平均粒径０．７５〜０．８５μｍの蛍光体を使用し、それにより、蛍光体層被覆可能面の単位面積あたりの蛍光体粒子の個数が３４×１０^６〜５０×１０^６個／ｍｍ^２である。ＰＤＰ４−２は、同じく液相合成法により製造された平均粒径が０．３６〜０．４１μｍの蛍光体を使用し、それにより蛍光体粒子の個数が３０８×１０^６〜４５５×１０^６個／ｍｍ^２である。このように、蛍光体層を構成する蛍光体の個数を増大することによって、蛍光体付量が等しい場合でも、紫外線を効率よく受光して、相対輝度を向上させることができる。
【発明の効果】
本発明によれば、蛍光体層を構成する蛍光体粒子の表面積の総和、あるいは蛍光体粒子の個数を従来に比して増大することにより、紫外線を効率よく受光して発光効率を向上することができる。それにより、蛍光体付量を増加することなく、高精細なＰＤＰであっても、高い輝度を達成することができる。また、液相合成法により蛍光体を製造することによって、化学両論的に高純度で、且つ、微粒な蛍光体を得ることができる。これにより、蛍光体粒子中の発光に寄与する体積の割合を増加して、従来よりも発光効率の高い蛍光体を得ることができる。したがって、液相合成法で合成した蛍光体を使用することにより、さらにＰＤＰの輝度を向上することができる。
【図面の簡単な説明】
【図１】本発明に係るプラズマディスプレイパネルの一例を示した斜視図である。
【図２】図１に示したプラズマディスプレイパネルに設けられた電極の配置を示した概略平面図である。
【図３】本発明に係るプラズマディスプレイパネルに設けられる放電セルの構造の他の例として、格子型のセル構造を示した概略平面図である。
【図４】本発明に係るプラズマディスプレイパネルに設けられる放電セルの構造の他の例として、ハニカム型のセル構造を示した概略平面図である。
【符号の説明】
１　　プラズマディスプレイパネル
１０　前面側基板、基板
１０ａ　情報表示面
２０　背面板側基板、（一方の）基板
３０、４０、５０　隔壁
３０ａ　隔壁表面
３１、４１、５１　放電セル
３１ａ　一方の基板表面
３５　蛍光体層[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a plasma display panel display device used for image display such as a television receiver, and more particularly, to a plasma display panel device having a phosphor layer which emits light when excited by ultraviolet rays.
[0002]
[Prior art]
2. Description of the Related Art A plasma display panel (hereinafter, abbreviated as PDP) has a glass substrate provided with two electrodes, and a large number of minute discharge spaces (hereinafter, referred to as cells) formed by partition walls provided between the substrates. ing. Phosphors that emit red (R), green (G), blue (B), and the like are applied to the side and bottom surfaces (one glass substrate) of the partition wall surrounding each cell, and Xe, Ne, or the like is a main component. Discharge gas is sealed. The cells have a predetermined shape such as a stripe shape, a lattice shape, a honeycomb shape or the like in plan view, and are arranged regularly in order to suppress the spread of discharge to a certain region. When a voltage is applied between the electrodes to cause discharge, ultraviolet light is generated, and the phosphor is excited to emit light. Desired information can be displayed by selectively discharging a predetermined cell or a part of the cell.
[0003]
In the PDP, one cell or a part of the cell which can be selectively discharged becomes a minimum light emitting unit, and three minimum light emitting units of R, G, and B which are close to each other become one pixel.
For example, in the case of a PDP having a screen size of 42 inches and a definition of VGA (Video Graphics Array), the number of pixels is 1,024 × 768, and the amount of phosphor per minimum light emission unit is about 0. 0.025 mg.
Conventionally, the particle size of a phosphor for PDP is about 2 to 10 μm, and is mainly manufactured by a solid phase synthesis method. The solid phase synthesis method is a method in which a predetermined amount of a compound containing an element constituting a phosphor matrix and a compound containing an activator element are mixed and fired at a predetermined temperature to obtain a phosphor by a solid-phase reaction.
[0004]
[Problems to be solved by the invention]
By the way, at present, PDPs tend to have higher definition. As the definition increases, the number of pixels provided on one panel increases, and images and the like can be displayed finer and more beautifully. However, as the number of pixels increases, the size of one pixel decreases, and the size of the minimum light emission unit also decreases. As a result, the amount of the phosphor that can be applied to one minimum light-emitting unit also decreases, causing a problem that the luminance decreases.
[0005]
Therefore, in order to improve the luminance, it is conceivable to increase the amount of phosphor per minimum emission unit to increase the amount of phosphor involved in light emission. However, when the amount of the fluorescent substance is increased in the cell in the limited space, the volume occupied by the fluorescent substance also increases, and the volume of the discharge space is narrowed accordingly. As a result, the amount of ultraviolet rays generated at the time of discharge is reduced, and the brightness may be further reduced.
[0006]
Further, ultraviolet rays generated by plasma discharge in the cell enter only around 100 nm near the surface of the phosphor particles. For example, in a phosphor produced by a conventional solid phase synthesis method and having an average particle size of 2 μm, the volume contributing to light emission is only about 18% of the particle volume, and the light emission efficiency is extremely low.
An object of the present invention is to provide a plasma panel display with high luminance even if the definition is improved by improving the luminous efficiency of the phosphor.
[0007]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1 includes a front substrate provided with an information display surface, a rear substrate disposed to face the front substrate at a predetermined interval, and A partition provided between the partition and a plurality of partitions between the substrates, a discharge cell formed by being surrounded by the partition and the substrate, and a phosphor layer provided inside the discharge cell, the discharge By performing plasma discharge in a cell, visible light is generated from the phosphor layer, and the phosphor layer is configured in a plasma display panel that performs information display by projecting the visible light onto the information display surface. The sum of the surface areas of the phosphor particles is 1 mm for the information display surface.²Per area, 100mm²More than 3,000mm²It is characterized by the following.
[0008]
Here, the total surface area of the phosphor particles may be obtained from the particle size distribution of the phosphor and the amount of the phosphor used to form the phosphor layer (the amount of the applied phosphor). The measurement may be performed with the body layer peeled off.
[0009]
According to the first aspect of the present invention, the sum of the surface areas of the phosphor particles constituting the phosphor layer is set to 1 mm on the information display surface.²Per area, conventional 90mm²From the extent, 100mm²More than 3,000mm²It has increased to the following. Ultraviolet light generated in the discharge cell enters only near the surface of the phosphor particles, for example, about 100 nm. Therefore, by increasing the surface area, it is possible to efficiently receive ultraviolet light and increase the amount of light emission. Therefore, luminous efficiency can be improved as compared with the related art. As a result, the luminance can be increased even for a high-definition PDP having a large number of pixels.
[0010]
According to a second aspect of the present invention, there is provided a front-side substrate having an information display surface, a rear-side substrate facing the front-side substrate at a predetermined interval, and a substrate provided between these substrates. Partitioning the space into a plurality, a discharge cell formed by being surrounded by the partition and the substrate, and a phosphor layer provided inside the discharge cell, and performing a plasma discharge in the discharge cell. By generating visible light from the phosphor layer and projecting the visible light on the information display surface to perform information display, in a plasma display panel, the number of phosphor particles constituting the phosphor layer, 7 million pieces / mm per unit area of information display surface²More than 30 billion pieces / mm²It is characterized by the following.
[0011]
Here, the number of phosphor particles can be counted using an electron microscope (for example, S-900, manufactured by Hitachi, Ltd.).
[0012]
According to the invention described in claim 2, the number of the phosphor particles constituting the phosphor layer is conventionally 700,000 / mm per unit area of the information display surface.²About 7 million pieces / mm²More than 30 billion pieces / mm²The following are extremely common. As described above, the ultraviolet rays generated in the discharge cells usually enter only near the surface of the phosphor particles. Therefore, by increasing the number of the phosphor particles, the ultraviolet rays are efficiently received and the emission amount is improved. be able to. Therefore, the luminous efficiency of the phosphor is improved, and higher luminance can be achieved even in the case of a high-definition PDP as compared with the related art.
[0013]
According to a third aspect of the present invention, there are provided two substrates which are arranged to face each other at a predetermined interval, a partition provided between the substrates to partition a space between the substrates into a plurality, and the partition and the substrate surround the partition. Display panel having a discharge cell formed by the above and a phosphor layer provided inside the discharge cell, the surface of the partition wall facing the inside of the discharge cell and the surface of one of the substrates are formed of a phosphor layer. When the surface is coatable, the total surface area of the phosphor particles constituting the phosphor layer is 1 mm in the phosphor layer coverable surface.²Around 40mm²More than 600mm²It is characterized by the following.
[0014]
Here, the surface area of the phosphor particles may be obtained from the particle size distribution of the phosphor and the amount of the phosphor used to form the phosphor layer (the amount of the phosphor), as described above. The measurement may be performed by peeling the phosphor layer from the cell.
[0015]
According to the third aspect of the present invention, the total surface area of the phosphor particles constituting the phosphor layer is reduced to 1 mm on the phosphor layer-coverable surface.²About the conventional 30mm²From the extent, 40mm²More than 600mm²It has increased to the following. As described above, since the ultraviolet rays generated in the discharge cells enter only near the surface of the phosphor particles, by increasing the surface area, it is possible to efficiently receive the ultraviolet rays and increase the light emission amount. Therefore, even with a high-definition PDP, the luminous efficiency of the phosphor is improved, so that the luminance can be improved.
[0016]
According to a fourth aspect of the present invention, there are provided two substrates which are arranged to face each other at a predetermined interval, a partition provided between the substrates to partition a space between the substrates into a plurality, and the partition and the substrate surround the partition. A plasma display panel including a discharge cell formed by the above method and a phosphor layer provided inside the discharge cell, the surface of the partition wall facing the inside of the discharge cell and the surface of one of the substrates are formed of a phosphor. When the layer can be covered, the number of the phosphor particles constituting the phosphor layer is 3,000,000 particles / mm per unit area of the phosphor layer-coverable surface.²Above, 5 billion pieces / mm²It is characterized by the following.
[0017]
Here, the number of phosphor particles can be counted using an electron microscope (for example, S-900, manufactured by Hitachi, Ltd.) in the same manner as described above.
[0018]
According to the fourth aspect of the present invention, the number of the phosphor particles constituting the phosphor layer is 2.5 million particles / mm per unit area of the phosphor layer coverable surface.²About 3 million pieces / mm²Above, 5 billion pieces / mm²The following are extremely common. As described above, since the ultraviolet rays generated in the discharge cells enter only near the surface of the phosphor particles, by increasing the number of the phosphor particles, it is possible to efficiently receive the ultraviolet rays and improve the emission amount. it can. Therefore, even with a high-definition PDP, higher luminance can be achieved as compared with the related art.
[0019]
According to a fifth aspect of the present invention, in the plasma display panel according to any one of the first to fourth aspects, the phosphor particles are formed by a liquid phase synthesis method in which a phosphor material is reacted in a liquid phase. It is characterized by being manufactured.
[0020]
Here, the liquid phase synthesis method refers to a reaction method in a liquid phase such as a reaction crystallization method, a coprecipitation method, and a sol-gel method.
[0021]
According to the fifth aspect of the present invention, the phosphor is manufactured by a liquid phase synthesis method in which the phosphor raw material is reacted in a liquid phase. Theoretically, a high-purity phosphor is easily obtained. On the other hand, in the conventional solid-phase synthesis method, since the reaction is a solid-solid reaction, surplus impurities that do not react and secondary salts generated by the reaction often remain, resulting in a stoichiometrically high-purity phosphor. Difficult to obtain. For this reason, by manufacturing a phosphor by a liquid phase synthesis method, the emission intensity of the obtained phosphor can be increased as compared with the related art, and the luminance of the PDP can be improved.
[0022]
Further, in the solid phase synthesis method, a phosphor is produced while repeatedly performing a solid phase reaction and a pulverizing step. Therefore, for example, when an attempt is made to produce a fine phosphor having a particle size of 2 μm or less, stress is applied to the phosphor at the time of pulverization, and as a result, lattice defects may occur in the crystal, and the luminous efficiency may be significantly reduced. On the other hand, in the liquid phase synthesis method, since the reaction is performed between element ions in the liquid phase, as described later, the average particle size, particle shape, particle size distribution, emission characteristics, and the like of the phosphor are more precisely controlled. And the phosphor can be atomized. Also, at this time, since no mechanical pulverization or the like is performed, even if the phosphor is atomized, a lattice defect or the like in a crystal that causes a decrease in luminous efficiency does not occur, and a phosphor with high emission intensity is obtained. be able to.
[0023]
Further, even if a phosphor having a particle size of 2 μm is formed by the solid phase synthesis method, as described above, the ultraviolet light generated in the discharge cell enters only near the surface, for example, about 100 nm. Therefore, the volume contributing to light emission was only about 18% of the volume of the phosphor particles. As the particle size of the phosphor increases, the proportion of the volume contributing to light emission in the particles decreases. Therefore, in the case of a phosphor produced by solid phase synthesis, the proportion of the volume contributing to light emission is at most about 18%. Likely to be.
[0024]
On the other hand, according to the liquid phase synthesis method, fine phosphor particles having a particle size of 2 μm or less can be favorably produced. Therefore, as compared with the phosphor particles manufactured by the solid phase synthesis method, the ratio of the volume contributing to light emission to the phosphor particle volume can be increased. Further, by making the particles fine, the number of phosphors contained in a unit mass can be increased, and the surface area of the phosphor particles can be increased. Thus, even if a phosphor having the same mass as that of the related art is used, it is possible to efficiently receive ultraviolet rays, increase the amount of emitted light, and improve the brightness of the PDP.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a plasma display panel according to the present invention will be described in detail with reference to the drawings.
A plasma display panel (PDP) of the present invention includes two substrates opposing each other at a predetermined interval, a partition provided between the substrates to partition a space between the substrates into a plurality, and the partition and the substrate. It comprises a discharge cell formed so as to be surrounded, and a phosphor layer provided inside the discharge cell. The PDP generates a plasma discharge in the discharge cell, thereby generating visible light from the phosphor. Then, the visible light is projected onto a light-transmitting substrate arranged on the display side to display various information on a display screen. In the present invention, as described later, the luminous efficiency of the phosphor particles is reduced by setting the surface area of the phosphor particles constituting the phosphor layer to a certain range or by setting the number of the phosphor particles to a certain range. The brightness of the PDP has been improved.
[0026]
First, a configuration example of a PDP according to the present invention will be described with reference to FIGS.
PDPs can be roughly classified into a DC type that applies a DC voltage and an AC type that applies an AC voltage, depending on the structure and operation mode of the electrodes. Although the PDP of the present invention may be of any type, FIG. 1 shows an AC type PDP 1.
[0027]
One of the two substrates 10 and 20 shown in FIG. 1 is a front plate 10 (front substrate) disposed on the display side, and the other is a rear plate 20 (rear substrate) disposed on the back side. is there. The front plate 10 and the rear plate 20 are opposed to each other at a predetermined interval by a partition 30 provided between the substrates 10 and 20.
[0028]
First, the configuration of the front plate 10 will be described.
The front plate 10 can be formed from a material that transmits visible light, such as soda lime glass. As shown in FIG. 2, the periphery of the front plate 10 is a storage portion 10a stored in a screen frame or the like formed of a plastic material or the like, and the inside of the storage portion 10a is an information display surface 10b. The information display surface 10b is an information display area on which information such as various images and videos is displayed. The size of the information display surface 10b is represented by the length of a diagonal line. For example, when the length of the diagonal line is 106 cm, it is 42 inches.
[0029]
As shown in FIG. 1, a discharge electrode 11, a dielectric layer 12, a protective layer 13, and the like are provided on a surface of the front plate 10 facing the back plate 20.
The discharge electrode 11 includes a scan electrode 11a and a sustain electrode 11b, and each of the electrodes 11a and 11b is formed in a band shape.
As shown in FIG. 2, the discharge electrodes 11 are provided so as to continuously traverse from the end 10c to the end 10d of the front plate 10, and are regularly arranged at predetermined intervals. Each discharge electrode 11 is connected to the panel drive circuit 15, and can apply a voltage to a desired electrode 11.
[0030]
As shown in FIG. 1, a dielectric layer 12 is provided so as to cover the entire surface of front plate 10 on which these discharge electrodes 11 are arranged. The dielectric layer 12 is made of a dielectric material, and is generally often made of a lead-based low-melting glass. In addition, the dielectric layer 12 may be formed of bismuth-based low-melting glass or a laminate of lead-based low-melting glass and bismuth-based low-melting glass.
[0031]
The surface of the dielectric layer 12 is entirely covered by the protective layer 13. The protective layer 13 is preferably a thin layer made of magnesium oxide (MgO).
[0032]
Next, the configuration of the rear plate 20 will be described.
The back plate 20 is formed to have substantially the same size as the front plate 10, and can be made of soda lime glass or the like, similarly to the front plate 10. A plurality of data electrodes 21, a dielectric layer 22, partition walls 30, and the like are provided on a surface of the back plate 20 facing the front plate 10.
[0033]
The data electrodes 21 are formed in a band shape similarly to the discharge electrodes 11, and are provided at predetermined intervals. The partition 30 is provided on both sides of the data electrode 21. As shown in FIG. 2, the data electrode 21 is divided at a central portion 24 of the back plate 20, and each is connected to the panel drive circuits 25a and 25b. By the panel drive circuit 25, a voltage can be applied to a desired electrode 21.
[0034]
As shown in FIG. 1, the entire surface of the back plate 20 on which the data electrodes 21 are arranged is covered with a dielectric layer 22. Like the dielectric layer 12, the dielectric layer 22 can be made of lead-based low-melting glass, bismuth-based low-melting glass, or a laminate of lead-based low-melting glass and bismuth-based low-melting glass. In addition, these dielectric materials are TiO₂It is preferable to mix the particles so that they also function as a visible light reflecting layer. When the dielectric layer 22 also functions as a visible light reflecting layer in this way, even if the visible light emitted from the phosphor layer 35 is irradiated on the back plate 20 side, it is reflected on the front plate 10 side, The light transmitted through the front plate 10 can be increased, and the luminance can be improved.
[0035]
A partition 30 is provided on the upper surface of the dielectric layer 22 so as to protrude from the rear plate 20 to the front plate 10. The partition 30 divides a space between the substrates 10 and 20 into a plurality of predetermined shapes, and forms the discharge cells 31 as described above. The partition 30 is formed from a dielectric material such as a glass material.
[0036]
The discharge cell 31 is a discharge space surrounded by the partition 30 and the substrates 10 and 20 as described above, and the side 30a of the partition 30 facing the inside of the discharge cell 31 and the bottom 31a of the discharge cell 31 have red. The phosphor layers 35 that emit light of any of (R), green (G), and blue (B) are regularly provided in the order of R, G, and B. A discharge gas mainly composed of a rare gas is sealed in the discharge cell 31. As the discharge gas, it is particularly preferable to use a mixed gas in which Ne is used as a main discharge gas and Xe which generates ultraviolet rays by discharge is mixed with the main discharge gas. The pressure at which the mixed gas is charged is not particularly limited, but is preferably, for example, about 66.7 mPa.
Note that the discharge cells 31 are arranged below the information display surface 10b when the substrates 10, 20 are arranged horizontally.
[0037]
The discharge cell 31 shown in FIG. 1 is of a so-called stripe type, in which partition walls 30 are provided on both sides of the data electrode 21 and formed in parallel grooves by the partition walls 30.
Here, the arrangement of the discharge cells 31 and the electrodes 11 and 21 will be described.
As shown in FIG. 2, the discharge electrode 11 and the data electrode 21 are orthogonal to each other in a plan view and are in a matrix. In one discharge cell 31, a large number of intersections between the discharge electrode 11 and the data electrode 21 are provided. Discharge can be selectively performed at the intersection of the discharge electrode 11 and the data electrode 21, whereby desired information can be displayed. Hereinafter, the space of a cell obtained by dividing the volume of one cell by the number of intersections between the discharge electrode 11 and the data electrode 21 in the cell is referred to as a minimum light emission unit. In the PDP 1, one pixel is formed by three minimum light emission units of R, G, and B adjacent to each other.
[0038]
FIG. 1 shows what is called an AC surface discharge type PDP, and sustain discharge for achieving a predetermined luminance is performed between the scan electrode 11a and the sustain electrode 11b.
[0039]
The cell structure of the PDP according to the present invention is not limited to the above-described stripe type, but is, for example, a lattice type in which partition walls 40 are provided in a grid form to form a substantially rectangular discharge cell 41 as shown in FIG. May be. In this case, at least one intersection of the discharge electrode and the data electrode is provided inside one discharge cell 41.
[0040]
Further, the cell structure may be a honeycomb type having partition walls 50 provided in a honeycomb shape as shown in FIG. In the case of a honeycomb-type cell structure, a repetitive structure divided by a partition in a substantially hexagonal shape is defined as one discharge cell 51, and a discharge electrode and a data electrode are provided inside one discharge cell 51 similarly to the lattice type. At least one intersection is provided.
Note that the lattice shape and the honeycomb shape refer to shapes in a plan view when the substrate surface of the back plate is horizontally arranged.
[0041]
Next, the composition, manufacturing method, surface area, number, and the like of the phosphor particles constituting the phosphor layer 35 will be described.
[0042]
The composition of the phosphor according to the present invention is not particularly limited, and examples thereof include JP-A-50-6410, JP-A-61-65226, JP-A-64-22987, JP-A-64-60671, and JP-A-1-168911. It is possible to apply the various known compositions described. Specifically, Y₂O₃, Zn₂SiO₄Such as metal oxides, Ca₅(PO₄) Phosphate represented by 3Cl, sulfide represented by ZnS, SrS, CaS, etc., Si, SiO₂And the like, a rare earth metal ion such as Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ag, Al , Mn, Sb, Zn or the like are preferably combined as an activator or a co-activator.
[0043]
Preferred examples of the crystal base are listed below.
ZnS, SrS, GaS, (Zn, Cd) S, SrGa₂S₄, YO₃, Y₂O₂S, Y₂O₃, Y₂SiO₃, SnO₂, Y₃Al₅O₁₂, Zn₂SiO₄, Sr₄Al₁₄O₂₅, CeMgAl₁₀O₁₉, BaAl₁₂O₁₉, BaMgAl₁₀O₁₇, BaMgAl₁₄O₂₃, Ba₂Mg₂Al₁₂O₂₂, Ba₂Mg₄Al₈O₁₈, Ba₃Mg₅Al₁₈O₃₅, (Ba, Sr, Mg) O.aAl₂O₃, (Ba, Sr) (Mg, Mn) Al₁₀O₁₇, (Ba, Sr, Ca) (Mg, Zn, Mn) Al₁₀O₁₇, Sr₂P₂O₇, (La, Ce) PO₄, Ca₁₀(PO₄)₆(F, Cl)₂, (Sr, Ca, Ba, Mg)₁₀(PO₄) 6Cl₂, GdMgB₅O₁₀, (Y, Gd) BO₃And the like.
[0044]
The compound containing the crystal host element and the activator or co-activator element is not particularly limited in terms of the composition of the element, and may be partially replaced with a homologous element, and emits visible light by absorbing excitation light in the ultraviolet region. Any combination may be used. In particular, it is preferable to use an inorganic oxide phosphor or an inorganic halide phosphor.
Specific examples of the phosphor used in the present invention are shown below, but the present invention is not limited to these compounds.
[0045]
[Blue-emitting phosphor compound]
BL1: Sr₂P₂O₇: Sn⁴⁺
BL2: Sr₄Al₁₄O₂₅: Eu²⁺
BL3: BaMgAl₁₀O₁₇: Eu²⁺
BL4: SrGa₂S₄: Ce³⁺
BL5: CaGa₂S₄: Ce³⁺
BL6: (Ba, Sr) (Mg, Mn) Al₁₀O₁₇: Eu²⁺
BL7: (Sr, Ca, Ba, Mg)₁₀(PO₄) 6Cl₂: Eu²⁺
BL8: ZnS: Ag
BL9: CaWO₄
BL10: Y₂SiO₅: Ce
BL11: ZnS: Ag, Ga, Cl
BL12: Ca₂B₅O₉Cl: Eu²⁺
BL13: BaMgAl₁₄O₂₃: Eu²⁺
BL14: BaMgAl₁₀O₁₇: Eu²⁺, Tb³⁺, Sm²⁺
BL15: BaMgAl₁₄O₂₃: Sm²⁺
BL16: Ba₂Mg₂Al₁₂O₂₂: Eu²⁺
BL17: Ba₂Mg₄Al₈O₁₈: Eu²⁺
BL18: Ba₃Mg₅Al₁₈O₃₅: Eu²⁺
BL19: (Ba, Sr, Ca) (Mg, Zn, Mn) Al₁₀O₁₇: Eu²⁺
[0046]
[Green-emitting phosphor compound]
GL1: (Ba, Mg) Al₁₆O₂₇: Eu²⁺, Mn²⁺
GL2: Sr₄Al₁₄O₂₅: Eu²⁺
GL3: (Sr, Ba) Al₂Si₂O₈: Eu²⁺
GL4: (Ba, Mg)₂SiO₄: Eu²⁺
GL5: Y₂SiO₅: Ce³⁺, Tb³⁺
GL6: Sr₂P₂O₇-Sr₂B₂O₅: Eu²⁺
GL7: (Ba, Ca, Mg)₅(PO₄)₃Cl: Eu²⁺
GL8: Sr₂Si₃O₈-2SrCl₂: Eu²⁺
GL9: Zr₂SiO₄, MgAl₁₁O₁₉: Ce³⁺, Tb³⁺
GL10: Ba₂SiO₄: Eu²⁺
GL11: ZnS: Cu, Al
GL12: (Zn, Cd) S: Cu, Al
GL13: ZnS: Cu, Au, Al
GL14: Zn₂SiO₄: Mn
GL15: ZnS: Ag, Cu
GL16: (Zn, Cd) S: Cu
GL17: ZnS: Cu
GL18: Gd₂O₂S: Tb
GL19: La₂O₂S: Tb
GL20: Y₂SiO₅: Ce, Tb
GL21: Zn₂GeO₄: Mn
GL22: CeMgAl₁₁O₁₉: Tb
GL23: SrGa₂S₄: Eu²⁺
GL24: ZnS: Cu, Co
GL25: MgO · nB₂O₃: Ce, Tb
GL26: LaOBr: Tb, Tm
GL27: La₂O₂S: Tb
GL28: SrGa₂S₄: Eu²⁺, Tb³⁺, Sm²⁺
[0047]
[Red emitting phosphor compound]
RL1: Y₂O₂S: Eu³⁺
RL2: (Ba, Mg)₂SiO₄: Eu³⁺
RL3: Ca₂Y₈(SiO₄)₆O₂: Eu³⁺
RL4: LiY₉(SiO₄)₆O₂: Eu³⁺
RL5: (Ba, Mg) Al₁₆O₂₇: Eu³⁺
RL6: (Ba, Ca, Mg)₅(PO₄)₃Cl: Eu³⁺
RL7: YVO₄: Eu³⁺
RL8: YVO₄: Eu³⁺, Bi³⁺
RL9: CaS: Eu³⁺
RL10: Y₂O₃: Eu³⁺
RL11: 3.5MgO, 0.5MgF₂GeO₂: Mn
RL12: YAlO₃: Eu³⁺
RL13: YBO₃: Eu³⁺
RL14: (Y, Gd) BO₃: Eu³⁺
[0048]
As the phosphor having the above composition, those produced by various methods such as a conventionally known solid-phase synthesis method and liquid-phase synthesis method can be applied, but the phosphor constituting the phosphor layer 35 according to the present invention can be used. The particles are preferably produced by a liquid phase synthesis method in which a phosphor material is reacted in a liquid phase to synthesize a phosphor.
[0049]
In the liquid phase synthesis method, a phosphor raw material is reacted in a liquid phase, so that the reaction is performed between element ions constituting the phosphor. Therefore, a stoichiometrically high-purity phosphor is easily obtained. On the other hand, in the conventional solid-phase synthesis method, since the reaction is a solid-solid reaction, surplus impurities that do not react and secondary salts generated by the reaction often remain, resulting in a stoichiometrically high-purity phosphor. Difficult to obtain. For this reason, by manufacturing a phosphor by a liquid phase synthesis method, the emission intensity of the obtained phosphor can be increased as compared with the related art, and the luminance of the PDP can be improved.
[0050]
Further, in the solid phase synthesis method, a phosphor is produced while repeatedly performing a solid phase reaction and a pulverizing step. Therefore, for example, when an attempt is made to produce a fine phosphor having a particle size of 2 μm or less, stress is applied to the phosphor at the time of pulverization, and as a result, lattice defects may occur in the crystal, and the luminous efficiency may be significantly reduced. On the other hand, in the liquid phase synthesis method, since the reaction is performed between element ions in the liquid phase, as described later, the average particle size, particle shape, particle size distribution, emission characteristics, and the like of the phosphor are more precisely controlled. And the phosphor can be atomized. Also, at this time, since no mechanical pulverization or the like is performed, even if the phosphor is atomized, a lattice defect or the like in a crystal that causes a decrease in luminous efficiency does not occur, and a phosphor with high emission intensity is obtained. be able to.
[0051]
Further, even if a phosphor having a particle size of 2 μm is formed by the solid phase synthesis method, as described above, the ultraviolet light generated in the discharge cell enters only near the surface, for example, about 100 nm. Therefore, the volume contributing to light emission was only about 18% of the volume of the phosphor particles. As the particle size of the phosphor increases, the proportion of the volume contributing to light emission in the particles decreases. Therefore, in the case of a phosphor produced by solid phase synthesis, the proportion of the volume contributing to light emission is at most about 18%. Likely to be.
[0052]
On the other hand, in the liquid phase synthesis method, as described below, not only phosphor particles having a particle size of 2 μm or less, but also phosphor particles having a particle size of 1.5 μm or less can be favorably produced. Therefore, as compared with the phosphor particles manufactured by the solid phase synthesis method, the ratio of the volume contributing to light emission to the phosphor particle volume can be increased. Further, by making the particles fine, the number of phosphors contained in a unit mass can be increased, and the surface area of the phosphor particles can be increased. Thus, even if a phosphor having the same mass as that of the related art is used, it is possible to efficiently receive ultraviolet rays, increase the amount of emitted light, and improve the brightness of the PDP.
[0053]
Hereinafter, a method for obtaining a phosphor having high emission intensity with fine particles by a liquid phase synthesis method will be specifically described.
The step of producing a phosphor using a liquid phase synthesis method includes a phosphor precursor forming step of mixing phosphor materials in a liquid phase to form a phosphor precursor, and a drying step of drying the phosphor precursor. And a process. After the drying step, a firing step is performed if necessary.
In producing the phosphor according to the present invention, the phosphor particles whose surfaces are coated with metal are basically obtained by baking the dried phosphor precursor. However, depending on the composition of the phosphor, the reaction conditions, and the like, the phosphor may be obtained from the phosphor precursor in the drying step without firing. In that case, the firing step may be omitted. After the firing step, a cooling step of cooling the obtained fired product, a step of performing a surface treatment of the phosphor, or the like may be performed.
Note that the phosphor precursor is an intermediate compound of the phosphor to be produced, and is a compound that becomes a phosphor by a treatment such as drying and baking as described above.
[0054]
First, the precursor forming step will be described. In the precursor forming step, a phosphor precursor is formed by a liquid phase synthesis method in which a phosphor raw material is reacted in a liquid phase.
In the present invention, the liquid phase synthesis method refers to a reaction method in a liquid phase such as a reaction crystallization method, a coprecipitation method, and a sol-gel method, and any liquid phase synthesis method may be applied. For example, for a red light emitting phosphor and a blue light emitting phosphor, it is particularly preferable to form a phosphor precursor by a reaction crystallization method in the presence of a protective colloid described below. By manufacturing in this manner, a phosphor having finer particles and a narrower particle size distribution and higher emission intensity can be obtained. Further, it is preferable that the green light emitting phosphor is formed by a coprecipitation method using silica as a phosphor matrix. By producing in this manner, fine particles having excellent emission intensity and short afterglow time can be obtained. Hereinafter, the reaction crystallization method and the coprecipitation method will be described.
[0055]
The reaction crystallization method is a method of synthesizing a phosphor precursor by mixing a solution containing an element serving as a raw material of a phosphor by utilizing a crystallization phenomenon. The crystallization phenomenon means that the solid phase precipitates out of the liquid phase when the physical or chemical environment changes due to cooling, evaporation, pH adjustment, concentration, etc., or when the state of the mixed system changes due to a chemical reaction. The phenomenon that comes.
The method for producing a phosphor precursor by the reaction crystallization method in the present invention means a production method by physical or chemical operation that can cause the above-mentioned crystallization phenomenon.
[0056]
As a solvent for applying the reaction crystallization method, any solvent may be used as long as the reaction raw materials are dissolved, but water is preferable from the viewpoint of easy control of the degree of supersaturation. When a plurality of reaction raw materials are used, the order of adding the raw materials may be simultaneous or different, and an appropriate sequence can be appropriately assembled depending on the activity.
[0057]
The coprecipitation method uses a coprecipitation phenomenon, mixes a solution or dispersion containing an element serving as a raw material of a phosphor, and further adds a precipitant, thereby becoming an activator around the phosphor matrix. It refers to a method of synthesizing a phosphor precursor in a state where a metal element or the like is deposited.
[0058]
As described above, it is preferable to use this coprecipitation method when obtaining a green phosphor composed of a silicate phosphor. In that case, a silicon compound such as silica is used as a phosphor matrix, and a solution containing a metal element such as Zn or Mn, which can constitute a green phosphor by firing, is mixed with the silicon compound. It is preferred to add a solution containing At this time, as the silica, fumed silica, wet silica, colloidal silica and the like can be preferably used.
[0059]
When synthesizing a precursor by a liquid phase synthesis method, including the above-mentioned reaction crystallization method and coprecipitation method, depending on the type of phosphor, reaction temperature, addition speed, addition position, stirring conditions, pH, etc. It is preferable to adjust physical properties. Ultrasonic waves may be applied when dispersing the phosphor matrix in the solution or during the reaction. It is also preferable to add a protective colloid, a surfactant, a polymer, etc. for controlling the average particle size. Concentration and / or aging of the liquid as needed after the addition of the raw materials is also a preferred embodiment.
[0060]
The particle size and aggregation state of the phosphor precursor particles are controlled by controlling the amount or rate of addition of the protective colloid to be added, the stirring conditions, and the like, and performing the reaction while keeping the dispersion state of the phosphor matrix in the solution in a preferable state. By controlling, the average particle size of the phosphor particles after firing can be made a desired size, and the particle size distribution can be narrowed.
In addition, when silica is used as a phosphor matrix and a phosphor precursor is formed by a coprecipitation method, firing may be performed by appropriately using colloidal silica whose dispersion state, particle size, and the like are adjusted to a desired state. The average particle diameter of the phosphor particles to be obtained can be set to a desired size.
[0061]
Next, a protective colloid which is preferably used for controlling the particle diameter particularly when forming a precursor by utilizing a reaction crystallization method will be described.
As such a protective colloid, various polymer compounds can be used regardless of whether they are natural or artificial, and proteins are particularly preferable. At that time, the average molecular weight of the protective colloid is preferably 10,000 or more, more preferably 10,000 or more and 300,000 or less, particularly preferably 10,000 or more and 30,000 or less.
[0062]
Examples of the protein include gelatin, a water-soluble protein, and a water-soluble glycoprotein. Specifically, there are albumin, ovalbumin, casein, soy protein, synthetic protein, protein synthesized by genetic engineering, and the like. Among them, gelatin can be particularly preferably used.
Examples of gelatin include lime-treated gelatin and acid-treated gelatin, and these may be used in combination. Further, hydrolysates of these gelatins and enzymatic degradation products of these gelatins may be used.
[0063]
Further, the protective colloid does not need to have a single composition, and various kinds of binders may be mixed. Specifically, for example, a graft polymer of the above gelatin and another polymer can be used.
[0064]
The protective colloid can be added to one or more of the raw material solutions. It may be added to all of the raw material solutions. By forming the phosphor precursor in the presence of the protective colloid, the phosphor precursors can be prevented from aggregating with each other, and the phosphor precursor can be made sufficiently small. This makes it possible to improve various characteristics of the phosphor, such as making the phosphor after firing finer, having a narrower particle size distribution, and improving light emission characteristics. When the reaction is performed in the presence of a protective colloid, it is necessary to sufficiently control the particle size distribution of the phosphor precursor and eliminate impurities such as secondary salts.
[0065]
As described above, in addition to adjusting the addition amount of the protective colloid, the particle size can be controlled by the addition rate of the reaction solution. At this time, the rate at which the solution containing the metal element serving as the activator is added to the mother liquor obtained by mixing or dispersing the compound containing the element serving as the phosphor matrix in the liquid may be adjusted. When the rate of adding the solution containing the metal element serving as the activator is increased, the concentration of the metal element serving as the reactant increases, so that a finer phosphor can be obtained.
[0066]
As described above, by controlling the particle size at the time of forming the precursor, it is desirable that the average particle size and the particle size distribution of the fired phosphor particles be in the following ranges.
[0067]
The preferred value of the average particle size of the phosphor particles after firing is 1.5 μm or less, more preferably 1.0 μm or less, and most preferably 0.5 μm or less.
[0068]
The average particle size of the phosphor is an average value obtained by measuring the average particle size of 300 phosphor particles in the phosphor layer using an electron microscope (for example, S-900, manufactured by Hitachi, Ltd.). Say. In addition, the particle size here refers to the length of the ridge of the phosphor particles when the phosphor particles are so-called normal crystals of a cube or an octahedron. When the phosphor particles are not normal crystals, for example, when the phosphor particles are spherical, rod-shaped, or tabular particles, the diameter refers to the diameter of a sphere equivalent to the volume of the phosphor particles.
[0069]
The particle size distribution of the phosphor particles is preferably as narrow as possible. Specifically, the variation coefficient of the particle size distribution is 300% or less. More preferably, it is 100% or less, and still more preferably 30% or less.
[0070]
The variation coefficient of the particle size distribution (width of the particle size distribution) is a value defined by the following equation (1). By using a phosphor having a narrow particle size distribution, a phosphor layer can be formed uniformly.
[Equation 1]
Size of particle size distribution (coefficient of variation) (%)
= (Standard deviation of particle size distribution / average value of particle size) × 100 (1)
[0071]
In the phosphor precursor forming step, as described above, by appropriately controlling the particle size and the like, and synthesizing the phosphor precursor, if necessary, by filtration, evaporation to dryness, centrifugation, or another method. The phosphor precursor is recovered, and then preferably washed.
[0072]
Further, it is preferable to remove impurities such as secondary salts from the phosphor precursor by passing through a desalting step prior to the drying step and the baking step.
As the desalting step, various membrane separation methods, coagulation sedimentation methods, electrodialysis methods, methods using ion-exchange resins, Nudel washing methods, and the like can be applied.
[0073]
By performing the desalting step, the electric conductivity after the desalting of the precursor is preferably in the range of 0.01 to 20 mS / cm, more preferably 0.01 to 10 mS / cm, and particularly preferably 0 to 10 mS / cm. 0.01 to 5 mS / cm.
When the electric conductivity is less than 0.01 mS / cm, the productivity is reduced. On the other hand, if it exceeds 20 mS / cm, since the by-salts and impurities cannot be sufficiently removed, the particles become coarse and the particle size distribution becomes wide, and the light emission intensity deteriorates.
Although any method can be used for measuring the electric conductivity, a commercially available electric conductivity measuring device may be used.
[0074]
In the present invention, the drying step is performed after the washing or the desalting step. 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 can be used.
Although the drying temperature is not limited, it is preferably a temperature around the temperature at which the solvent used evaporates or more, specifically, it is preferably in the range of 50 to 300 ° C. When the drying temperature is high, firing may be performed simultaneously with drying, and the phosphor may be obtained without performing the firing step described below.
[0075]
In the firing step, any method may be used, and the firing temperature and time may be appropriately adjusted. For example, a desired phosphor can be obtained by filling the phosphor precursor into an alumina boat and firing it at a predetermined temperature in a predetermined gas atmosphere. The gas atmosphere may be any condition such as a reducing atmosphere, an oxidizing atmosphere, or a sulfide, or an inert gas, and may be appropriately selected.
As an example of preferable firing conditions, firing may be performed at 600 ° C. to 1800 ° C. for an appropriate time in the air. Also effective is a method of baking at about 800 ° C. to oxidize the organic matter and then baking at 1100 ° C. for 90 minutes in the air.
[0076]
As the firing device (firing container), any device currently known can be used. For example, a box furnace, a crucible furnace, a cylindrical tube type, a boat type, a rotary kiln and the like are preferably used. As the atmosphere, an oxidizing, reducing, or inert gas can be used in accordance with the composition of the precursor.
[0077]
During firing, a sintering inhibitor may be added as necessary. When a sintering inhibitor is added, it can be added as a slurry when the phosphor precursor is formed. The powdered material may be mixed with the dried precursor and fired.
The sintering inhibitor is not particularly limited, and is appropriately selected depending on the type of the phosphor and the firing 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.₂However, firing at 1700 ° C or lower requires Al₂O₃Are each preferably used.
Further, after the firing, a reduction treatment or an oxidation treatment may be performed as necessary.
[0078]
After the firing step, various steps such as a cooling step, a surface treatment step, and a dispersion step may be performed, or classification may be performed.
[0079]
In the cooling step, a process of cooling the fired product obtained in the firing step is performed. At this time, the fired product can be cooled while being filled in the firing device.
Although the cooling treatment is not particularly limited, it can be appropriately selected from known cooling methods. For example, a method of lowering the temperature by leaving it alone or a method of forcibly lowering the temperature while controlling the temperature using a cooler can be used. Any of them may be used.
[0080]
The phosphor produced by the present invention can be subjected to surface treatment such as adsorption and coating for various purposes. The point at which the surface treatment is performed depends on the purpose, and the effect becomes more remarkable when appropriately selected. For example, when preparing a phosphor paste as described below, it is preferable to perform a surface treatment to improve the dispersibility of the phosphor. As described above, a phosphor can be manufactured.
[0081]
Next, the total and the number of the surface areas of the phosphor particles in the phosphor layer 35 will be described.
First, as one embodiment of the present invention, the surface area of the phosphor particles constituting the phosphor layer 35 is 1 mm of the information display surface 10b.²Per area, 100mm²More than 3,000mm²The following is recommended. At this time, more preferably 185 mm²More than 3,000mm²It is as follows.
[0082]
The surface area may be determined from the particle size distribution of the phosphor and the amount of the phosphor used to form the phosphor layer (the amount of the phosphor applied), and is measured by actually peeling the phosphor layer from the discharge cell. May be.
[0083]
Hereinafter, "1 mm of the information display surface²Phosphor particles constituting the phosphor layer per 1 mm of the information display surface)²Phosphor particles "or" phosphor particles per unit area of the information display surface ".
[0084]
As described above, 1 mm of the information display surface 10b²The sum of the surface area of the phosphor particles per²From the extent, 100mm²More than 3,000mm²By increasing to below, it is possible to efficiently receive ultraviolet rays and increase the amount of emitted light. In particular, by using a phosphor having an average particle size of 1.5 μm or less and having a high emission intensity produced by the above-described production method, the phosphor can be compared with a phosphor produced by a conventional solid-phase production method. The number of phosphor particles contained in the unit mass of the phosphor increases, and the surface area increases. Further, as the phosphor particles are atomized, the ratio of the volume of each phosphor particle that contributes to light emission increases, and the luminous efficiency of the phosphor improves. Therefore, even in the case of the high-definition PDP 1, the surface area of the phosphor particles can be easily increased without increasing the amount of the phosphor per unit area of the information display surface 10b. Further, since the amount of the phosphor applied does not increase, the discharge space in the discharge cell 31 is not narrowed. Therefore, the brightness of PDP 1 can be further improved.
[0085]
Further, as another aspect of the present invention, when the surface 30a and the bottom surface 31a of the partition wall 30 facing the inside of the discharge cell 31 are made to be a phosphor layer-coverable surface that can be covered with a phosphor layer, the phosphor layer 35 The total surface area of the phosphor particles constituting the phosphor layer is 1 mm.²Around 40mm²More than 600mm²The following is recommended. At this time, more preferably, 100 mm²More than 600mm²It is as follows.
[0086]
In the following, the term “phosphor particles constituting the phosphor layer per unit area of the phosphor layer-coverable surface” refers to “1 mm of the phosphor layer-coverable surface”.²Phosphor particles per unit area ”or“ phosphor particles per unit area of the phosphor layer-coverable surface ”.
[0087]
As described above, 1 mm of the phosphor layer-coverable surface²The total surface area of the phosphor particles per unit²From the extent, 40mm²More than 600mm²By increasing to below, it is possible to efficiently receive ultraviolet rays and increase the amount of emitted light. Therefore, even if the PDP 1 has a high definition, the luminous efficiency of the phosphor is improved, so that the luminance can be improved.
[0088]
Further, similarly to the above, by using a phosphor having an average particle size of 1.5 μm or less and a high emission intensity produced by a liquid phase synthesis method, the phosphor particles contained in the unit mass of the phosphor can be obtained. The number increases, the surface area increases, and the proportion of the volume that contributes to the emission of each phosphor particle increases. Therefore, even in the case of the high-definition PDP 1, the surface area of the phosphor particles can be easily increased without increasing the amount of phosphor per unit area of the phosphor layer-coverable surface. Therefore, the brightness of PDP 1 can be further improved.
[0089]
Further, as another aspect of the present invention, the number of phosphor particles per unit area of the information display surface is set at 7,000,000 / mm.²More than 30 billion pieces / mm²The following is recommended. At this time, more preferably, 100 million pieces / mm²More than 30 billion pieces / mm²It is as follows.
[0090]
Here, the number of phosphor particles can be counted using an electron microscope (for example, S-900, manufactured by Hitachi, Ltd.).
[0091]
As described above, the number of phosphor particles per unit area of the information display surface 10b is reduced to 700,000 / mm of the conventional size.²7 million pieces / mm²More than 30 billion pieces / mm²By increasing to below, the surface area of the phosphor particles increases, whereby it is possible to efficiently receive ultraviolet rays and improve the amount of emitted light. Therefore, the luminous efficiency of the phosphor is improved, and even if the PDP 1 has high definition, higher luminance can be achieved as compared with the related art.
[0092]
Further, in the same manner as described above, by using a phosphor having an average particle size of 1.5 μm or less and a high emission intensity produced by a liquid phase synthesis method, the phosphor particles contained in the unit mass of the phosphor can be obtained. The number increases, the surface area increases, and the proportion of the volume that contributes to the emission of each phosphor particle increases. Therefore, even in the case of the high-definition PDP 1, the number of phosphor particles can be easily increased without increasing the amount of phosphor per unit area of the information display surface 10b. Therefore, the brightness of PDP 1 can be further improved.
[0093]
As still another embodiment of the present invention, the number of phosphor particles per unit area of the phosphor layer-coverable surface is set to 3,000,000 particles / mm.²Above, 5 billion pieces / mm²The following may be used. At this time, more preferably, 300 million pieces / mm²Above, 5 billion pieces / mm²It is as follows.
[0094]
As described above, the number of phosphor particles per unit area of the phosphor layer-coverable surface is reduced to 2.5 million particles / mm in the related art.²3 million pieces / mm²Above, 5 billion pieces / mm²By increasing the amount below, it is possible to efficiently receive ultraviolet rays and improve the amount of emitted light. Therefore, even with the high-definition PDP 1, higher brightness can be achieved as compared with the related art.
[0095]
Also, in this case, similarly to the above, by using a phosphor having an average particle diameter of 1.5 μm or less and having a high emission intensity manufactured by a liquid phase synthesis method, the phosphor is included in the unit mass of the phosphor. As the number of phosphor particles increases, the surface area increases, and the ratio of the volume of each phosphor particle that contributes to light emission increases. Therefore, even in the case of the high-definition PDP 1, the number of phosphor particles can be easily increased without increasing the amount of phosphor per unit area of the phosphor layer coverable surface. Therefore, the brightness of PDP 1 can be further improved.
[0096]
In order to form the phosphor layer 35 as described above, a phosphor paste is prepared by mixing a phosphor and a solvent as described below, and a predetermined amount of the phosphor paste is applied to the inside of the discharge cell 31. Alternatively, after filling, the organic component in the paste may be removed by drying or baking. As a result, the phosphor layer 35 having the phosphor particles attached to the partition wall side surface 30a and the discharge cell bottom surface 31a is formed.
[0097]
Hereinafter, a method for forming the phosphor layer 35 will be described in detail.
In forming the phosphor layer 35, the phosphor paste may be adjusted as described above. The phosphor paste is obtained by dispersing a phosphor in a mixture of a binder, a solvent, a dispersant, and the like, and adjusting the viscosity to an appropriate level. The content of the phosphor in the phosphor paste is preferably in the range of 30% by mass to 60% by mass.
[0098]
Prior to the preparation of the phosphor paste, it is preferable to apply a surface treatment such as attaching or coating an oxide or a fluoride or the like to the surface of the phosphor particles in order to improve the dispersibility of the phosphor particles in the paste. Such oxides include, for example, magnesium oxide (MgO), aluminum oxide (Al₂O₃), Silicon oxide (SiO₂), Indium oxide (InO)₃), Zinc oxide (ZnO), yttrium oxide (Y₂O₃). Among them, SiO₂Is known as a negatively charged oxide, while ZnO, Al₂O₃, Y₂O₃Are known as positively charged oxides, and it is particularly effective to attach or coat these oxides.
[0099]
The average particle size of the oxide to be attached is considerably smaller than the average particle size of the phosphor particles, and the amount of these oxides attached to the surface of the phosphor particles is from 0.05% by mass to 2. It is appropriate to set it in the range of 0% by mass. This is because if it is less than this range, the effect is small, and if it is too large, vacuum ultraviolet rays generated in the plasma may be absorbed, and the panel luminance may be reduced. Examples of the fluoride to be attached or coated on the surface of the phosphor particles include magnesium fluoride (MgF₂) Or aluminum fluoride (AlF)₃).
[0100]
Next, a binder, a solvent, a dispersant, and the like that are mixed with the phosphor when preparing the phosphor paste will be described.
Ethyl cellulose or polyethylene oxide (polymer of ethylene oxide) may be mentioned as a binder suitable for dispersing the phosphor particles well, and particularly, an ethoxy group (-OC₂H₅) Is preferably used. Further, a photosensitive resin can be used as the binder. The content of the binder is preferably in the range of 0.15% by mass to 10% by mass. In order to adjust the shape of the phosphor paste applied between the partition walls, the content of the binder is preferably set to a relatively large value as long as the paste viscosity does not become too high.
[0101]
As the solvent, a mixture of an organic solvent having a hydroxyl group (OH group) is preferably used. Specific examples of the organic solvent include terpineol (C₁₀H₁₈O), butyl carbitol acetate, pentanediol (2,2,4-trimethylpentanediol monoisobutyrate), dipentene (Dipentene, also known as Limonen), butyl carbitol and the like. A mixed solvent obtained by mixing these organic solvents is excellent in solubility for dissolving the above-mentioned binder, and good in dispersibility of the phosphor paste. As such a mixed solvent, for example, a 1: 1 mixed solution of terpioneol and pentadiol is exemplified.
[0102]
In order to improve the dispersion stability of the phosphor particles in the phosphor paste, it is preferable to add a surfactant as a dispersant. The content of the surfactant in the phosphor paste is preferably 0.05% by mass to 0.3% by mass from the viewpoint of effectively improving the dispersion stability or effectively eliminating the electricity described below.
[0103]
As specific examples of the surfactant, (a) an anionic surfactant, (b) a cationic surfactant, and (c) a nonionic surfactant can be used. There is something.
(A) Examples of the anionic surfactant include fatty acid salts, alkyl sulfates, ester salts, alkyl benzene sulfonates, alkyl sulfosuccinates, and naphthalene sulfonate polycarboxylic acid polymers.
(B) Examples of the cationic surfactant include an alkylamine salt, a quaternary ammonium salt, an alkyl betaine, and an amine oxide.
(C) Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene derivative, sorbitan fatty acid ester, glycerin fatty acid ester, and polyoxyethylene alkylamine.
[0104]
Further, it is preferable to add a charge removing substance to the phosphor paste. The above-mentioned surfactants also generally have a charge eliminating action for preventing charging of the phosphor paste, and many of them correspond to charge eliminating substances. However, since the static elimination action varies depending on the type of the phosphor, the binder, and the solvent, it is preferable to conduct a test on various types of surfactants and select a surfactant having a good result.
[0105]
Examples of the charge removing substance include fine particles made of a conductive material in addition to the surfactant. As the conductive fine particles, fine carbon powders such as carbon black, fine graphite powders, fine powders of metals such as Al, Fe, Mg, Si, Cu, Sn and Ag, and fine powders of these metal oxides Is mentioned. The amount of such conductive fine particles to be added is preferably in the range of 0.05 to 1.0% by mass based on the phosphor paste.
[0106]
By adding the charge removing substance to the phosphor paste, the phosphor paste is charged, for example, the swelling of the phosphor layer 35 at the break of the data electrode 21 in the panel central portion 24 or the phosphor paste applied to the cell 31 It is possible to prevent the formation of the phosphor layer 35 from being poorly formed, such as a slight variation in the amount and the state of adhesion to the groove, and to form a uniform phosphor layer for each cell 31.
[0107]
When a surfactant or carbon fine powder is used as the charge removing substance as described above, the charge removing substance is also evaporated or burned off in the phosphor baking step of removing the solvent and the binder contained in the phosphor paste. Therefore, the charge removing substance does not remain in the phosphor layer after firing. Therefore, there is no possibility that driving (light emitting operation) of the PDP will be affected by the residual charge removing substance remaining in the phosphor layer.
[0108]
Viscosity of phosphor paste mixed with above (shear rate 100 sec at 25 ° C.)^-1Is preferably adjusted to 20 Pa · s or less, preferably 10 Pa · s to 0.1 Pa · s.
[0109]
When dispersing the phosphor in the various mixtures, for example, a medium medium such as a high-speed stirring impeller type disperser, a colloid mill, a roller mill, a ball mill, a vibration ball mill, an attritor mill, a planetary ball mill, and a sand mill are moved in the apparatus. A device that atomizes by both the collision and the shearing force, a dry disperser such as a cutter mill, a hammer mill, and a jet mill, an ultrasonic disperser, a high-pressure homogenizer, and the like can be used.
[0110]
In addition, at the time of preparing the phosphor paste, from the viewpoint of preventing deterioration of various properties such as the luminance of the phosphor, the dispersion treatment is performed while controlling the temperature of the dispersion from the start to the end so as not to exceed 70 ° C. The dispersion treatment is more preferably performed while controlling the temperature not to exceed 50 ° C.
[0111]
When the phosphor paste adjusted as described above is applied or filled in the discharge cells 31, various methods such as a screen printing method, a photoresist film method, and an ink jet method can be used.
[0112]
In particular, in the inkjet method, even when the pitch of the partition walls 30 is narrow and the discharge cells 31 are finely formed, the phosphor paste can be easily or accurately and uniformly applied between the partition walls 30 at low cost with high accuracy. It is preferred. In the present invention, since the phosphor can be manufactured into fine particles of 1.5 μm or less by the liquid phase synthesis method, clogging of the nozzle, defective ejection, and precipitation of the phosphor particles are suppressed even when the inkjet method is applied. The thin phosphor layer 35 can be formed accurately and uniformly.
[0113]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples 1 to 4, but the present invention is not limited thereto.
[0114]
[Example 1]
In the first embodiment, two PDPs 1-1 and 1-2 having different surface areas of the phosphor particles per unit area of the information display surface 10b in the PDP 1 shown in FIG. 1 were manufactured. First, the manufacture of the phosphor will be described.
[0115]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-1
As described below, a precursor was formed by a reaction crystallization method in the presence of a protective colloid, and the precursor was fired to produce a blue light-emitting phosphor B-1.
[0116]
First, 9 g of gelatin (average molecular weight: about 10,000) was dissolved in 300 g of pure water to prepare solution A. At the same time, 1.76 g of barium nitrate, 1.92 g of magnesium nitrate hexahydrate, 28.13 g of aluminum nitrate nonahydrate and 0.33 g of europium nitrate hexahydrate are dissolved in 136.48 g of pure water, and the solution B is dissolved. It was adjusted. Liquid C was prepared by mixing 23.33 g of aqueous ammonia (28%) with 124.07 g of pure water.
Next, while stirring the solution A, the solution B and the solution C were simultaneously added to the surface of the solution A by a double jet at an addition rate of 4.96 cc / min using a roller pump.
[0117]
After the completion of the addition of the liquids B and C, the solid-liquid separation was performed by suction filtration, and the liquid was sufficiently washed with pure water. Next, drying was performed at 100 ° C. for 12 hours to obtain a dried precursor.
The obtained dried precursor was baked at 600 ° C. for 1 hour in the air to remove residual organic substances such as gelatin from the precursor. Thereafter, the mixture was calcined at 1600 ° C. for 3 hours in a reducing atmosphere of 95% nitrogen and 5% hydrogen to obtain a blue light-emitting phosphor B-1. The average particle size of the obtained phosphor was 0.82 μm as determined by observation with an electron microscope.
[0118]
(2) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-2
In the same manner as in (1) above, a precursor was formed by a reaction crystallization method in the presence of a protective colloid, and the precursor was baked to produce a blue light-emitting phosphor B-2.
[0119]
First, a solution A was prepared by dissolving 15 g of gelatin (average molecular weight: about 10,000) in 300 g of pure water. At the same time, 3.55 g of barium nitrate, 3.85 g of magnesium nitrate hexahydrate, 56.27 g of aluminum nitrate nonahydrate and 0.67 g of europium nitrate hexahydrate were dissolved in 122.97 g of pure water, and the solution B was dissolved. It was adjusted. Further, 46.67 g of aqueous ammonia (28%) was mixed with 98.15 g of pure water to prepare a liquid C.
Next, while stirring the solution A, the solution B and the solution C were simultaneously added to the surface of the solution A by a double jet at an addition rate of 10.1 cc / min using a roller pump.
[0120]
After the addition of the liquids B and C was completed, solid-liquid separation, baking, etc. were performed in the same manner as in the above (1) to produce a blue light emitting phosphor B-2. When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.38 μm.
[0121]
(3) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-1
A green light-emitting phosphor G-1 was produced by forming a precursor of the green light-emitting phosphor G-1 by a coprecipitation method using silicon dioxide as a phosphor matrix, followed by firing.
[0122]
First, silicon dioxide (Aerosil 130 manufactured by Nippon Aerosil Co., Ltd., BET specific surface area 130 m²/ G) 4.51 g was mixed with 297.95 g of pure water to prepare solution A. At the same time, a solution B was prepared by dissolving 42.39 g of zinc nitrate hexahydrate and 2.15 g of manganese nitrate hexahydrate in 126.84 g of pure water. Then, 21.90 g of aqueous ammonia (28%) was mixed with 125.67 g of pure water to prepare a liquid C.
Next, while stirring the solution A, the solution B and the solution C were simultaneously added to the surface of the solution A by a double jet at an addition rate of 9.78 cc / min using a roller pump.
[0123]
After the completion of the addition of the liquids B and C, the solid-liquid separation was performed by suction filtration, and the liquid was sufficiently washed with pure water. Next, drying was performed at 100 ° C. for 12 hours to obtain a dried precursor.
The obtained precursor was fired at 1200 ° C. for 3 hours in an atmosphere of 100% nitrogen to obtain a green light-emitting phosphor G-1.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.78 μm.
[0124]
(4) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-2
In the above (3), a green light-emitting phosphor is used in the same manner as in the above (3) except that a mixture of 15.02 g of colloidal silica (KLEBOSOL30R25, 30 wt%, manufactured by Clariant) in 287.38 g of pure water is used as the liquid A. G-2 was produced.
When the average particle size of the obtained green light-emitting phosphor G-2 was determined by microscopic observation, it was 0.38 μm.
[0125]
(5) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-1
A precursor was formed by a reaction crystallization method in the presence of a protective colloid, and then calcined to produce a red light-emitting phosphor. This will be described in detail below.
[0126]
First, a solution A was prepared by dissolving 9 g of gelatin (average molecular weight 10,000) in 300 g of pure water. At the same time, 13.8 g of yttrium nitrate hexahydrate, 9.20 g of gadolinium nitrate and 1.30 g of europium nitrate hexahydrate were dissolved in pure water to prepare 150 ml of solution B. Further, boric acid (H₃BO₃3.) 3.60 g was dissolved in pure water to prepare 150 ml of solution C.
Next, while stirring the solution A, the solution B and the solution C were simultaneously added to the surface of the solution A by a double jet at an addition rate of 10.2 cc / min using a roller pump.
[0127]
After the completion of the addition of the liquids B and C, the solid-liquid separation was performed by suction filtration, and the liquid was sufficiently washed with pure water. Next, drying was performed at 100 ° C. for 12 hours to obtain a dried precursor.
The obtained precursor was calcined at 1400 ° C. for 3 hours in an air atmosphere to obtain a red light emitting phosphor R-1.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.77 μm.
[0128]
(6) Red phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-2
In the same manner as in the above (5), a precursor was formed by a reaction crystallization method in the presence of a protective colloid, and the precursor was fired to produce a red light emitting phosphor R-2. The details will be described below.
[0129]
First, a solution A was prepared by dissolving 15 g of gelatin (average molecular weight: about 10,000) in 300 g of pure water. 26.76 g of yttrium nitrate hexahydrate, 18.40 g of gadolinium nitrate and 2.60 g of europium nitrate hexahydrate were dissolved in pure water to prepare 150 ml of solution B. Further, 150 ml of solution C was prepared by dissolving 7.20 g of boric acid in pure water.
Next, while stirring the solution A, the solution B and the solution C were simultaneously added to the surface of the solution A by a double jet at an addition rate of 30.1 cc / min using a roller pump.
[0130]
After the addition of the liquids B and C was completed, solid-liquid separation, drying, baking and the like were performed in the same manner as in the above (5) to produce a red light emitting phosphor R-2.
The average particle size of the obtained phosphor was determined by observation with an electron microscope, and was found to be 0.39 μm.
[0131]
2. Adjustment of phosphor paste
Phosphor pastes were prepared using the light-emitting phosphors B-1, B-2, G-1, G-2, R-1, and R-2 produced in the above 1 respectively. At the time of the adjustment, the solid concentration of each of the phosphors B-1, B-2, G-1, G-2, R-1, and R-2 was set to 40% by mass, and ethyl cellulose and polio were used. Each was mixed with a 1: 1 mixture of xylene alkyl ether, terpineol and pentadiol. Each of the obtained mixtures was used as a phosphor paste B-1, B-2, G-1, G-2, R-1, or R-2 to be applied in a PDP cell described later.
[0132]
3. Manufacture of PDP
(1) Production of PDP1-1
Using the blue light-emitting phosphor paste B-1, green light-emitting phosphor paste G-1, and red light-emitting phosphor paste R-1 prepared above, PDP1 shown in FIG. 1 was manufactured. At this time, as described above, 1 mm of the information display surface 10b is used.²The total of the surface area of the phosphor particles per unit is 200 mm²That's it.
The size of the information display surface 10b was a 42-inch size with a diagonal of 106 cm, and the definition was a VGA (1,024 × 768 pixels).
[0133]
First, scan electrodes 11a and sustain electrodes 11b were formed on a glass substrate serving as front plate 10 by an inkjet method using a nozzle having a diameter of 50 μm. At this time, while keeping the distance between the nozzle tip and the front plate at 1 mm, the nozzle tip scans a predetermined position on the front plate 10 while discharging the electrode material ink to form a scanning electrode 11a having an electrode width of 60 μm. Each of the sustain electrodes 11b was formed to form a discharge electrode 11.
Next, a low-melting glass is printed on the front plate 10 via the discharge electrodes 11 and fired at 500 to 600 ° C. to form a dielectric layer 12. The protective film 13 was formed by beam evaporation.
[0134]
On the other hand, a data electrode 21 was formed on a glass substrate serving as a back plate 20. Similarly to the above, a data electrode 21 having a width of 60 μm was formed using a nozzle having a diameter of 50 μm while maintaining a distance of 1 mm from the back plate 20 and scanning a predetermined position. Next, stripe-shaped barrier ribs 30 were formed so as to be located on both sides of the data electrode 21. This was performed by printing low-melting glass at a pitch of 0.2 mm and firing it.
The electrodes 11, 21 and the partition 30 are provided below the information display surface 10b when the front plate 10 is horizontally arranged.
[0135]
Further, the phosphor pastes B-1, G-1, R-R which emit light of each color adjusted in the above 2 are provided on the bottom surface 31a facing the inside of the cell 31 partitioned by the partition wall 30 and the side surface 30a of the partition wall 30. 1 was applied to adjacent cells one by one in a regular order. The phosphor pastes B-1, R-1, and G-1 used at the time of application each used an average of 0.0635 mg (0.0254 mg of a phosphor-containing substance) per one minimum emission unit. At this time, 1 mm of the information display surface 10b of the blue light emitting phosphor B-1 was used.²The total surface area of the phosphor particles per unit is 226 mm²It became. The green light-emitting phosphor G-1 was 237 mm²240 mm for the red light emitting phosphor R-1²It became.
[0136]
Then, the front plate 10 on which the electrodes 11, 21 and the like are arranged and the rear plate 20 are aligned so that their respective electrode arrangement surfaces face each other, and the gap is kept about 1 mm by the partition wall 30. The periphery is sealed with seal glass. A gas mixture of xenon (Xe), which generates ultraviolet rays by discharge, and neon (Ne), a main discharge gas, was sealed between the substrates 10 and 20, and hermetically sealed, followed by aging. At this time, the sealing pressure was 66.7 mPa.
Manufactured as described above, it was designated as PDP1-1.
[0137]
(2) Production of PDP1-2
PDP1-2 was prepared in the same manner as PDP1-1, except that in 3 (1) above, blue light-emitting phosphor paste B-2, green light-emitting phosphor paste G-2, and red light-emitting phosphor paste R-2 were used. Manufactured. The phosphor pastes B-2, R-2, and G-2 used at the time of coating have an average of 0.0635 mg per one minimum light-emitting unit similarly to PDP1-1.
As a result, 1 mm of the information display surface 10b of the blue light emitting phosphor B-2²The total surface area of the phosphor particles per unit is 487 mm²It became. In addition, the green light-emitting phosphor G-2 was 487 mm.²475 mm for the red light emitting phosphor R-2²It became.
[0138]
[Comparative Example 1]
For comparison with the above-mentioned Example 1, a phosphor was produced by a solid phase synthesis method, and 1 mm of the information display surface 10b was formed using the obtained phosphor.²Phosphor surface area per unit is 100mm²A PDP was manufactured as follows.
First, a method of manufacturing the phosphor of each color will be described.
[0139]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-3
As a raw material, barium carbonate (BaCO₃), Magnesium carbonate (MgCO₃), Aluminum oxide (α-Al₂O₃) Are mixed at a molar ratio of 1: 1: 5 to prepare a mixture. Next, a predetermined amount of europium oxide (Eu) was added to the mixture.₂O₃) Is added. Then, an appropriate amount of flux (AlF₂, BaCl₂), And calcined at 1600 ° C. for 3 hours in a reducing atmosphere of 95% nitrogen and 5% hydrogen to obtain a phosphor. The obtained phosphor was classified, and the one having an average particle size of 2.16 μm was designated as blue light-emitting phosphor B-3.
[0140]
(2) Green emitting phosphor (ZnSiO₄: Mn) Production of G-3
As raw materials, zinc oxide (ZnO), silicon dioxide (SiO₂) Is mixed at a molar ratio of 2: 1 to prepare a mixture. Next, a predetermined amount of manganese oxide (Mn) was added to the mixture.₂O₃) Was added and mixed in a ball mill, followed by baking at 1,200 ° C. for 3 hours in an atmosphere of 10% nitrogen to obtain a phosphor. The obtained phosphor was classified, and the one having an average particle size of 2.12 μm was designated as green light-emitting phosphor B-3.
[0141]
(3) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺)Manufacturing of
Yttrium oxide (Y₂O₃) And gadolinium oxide (Gd₂O₃) And europium oxide (Eu)₂O₃) And boric acid (H₃BO₃) Was blended so that the atomic ratio of Y, Gd, and B was 0.60: 0.35: 1.0 to prepare a mixture. Next, a predetermined amount of europium oxide (Eu) was added to the mixture.₂O₃) Is added. The mixture was mixed with an appropriate amount of flux in a ball mill, and fired at 1400 ° C. for 3 hours in an air atmosphere to obtain a phosphor. The obtained phosphor was classified, and one having an average particle size of 2.10 μm was designated as a red light-emitting phosphor R-3.
[0142]
2. Adjustment of phosphor paste
Except for using the phosphors B-3, G-3, and R-3 obtained above, the phosphor pastes B-3, G-3, and R-3 for each color were adjusted in the same manner as in Example 1-2. did.
[0143]
3. Manufacture of PDP
Example 3 (1) is the same as Example 1-3 except that the blue light emitting phosphor paste B-3, the green light emitting phosphor paste G-3, and the red light emitting phosphor paste R-3 are used. PDP was manufactured. The phosphor pastes B-3, R-3, and G-3 used at the time of coating have an average of 0.0635 mg per minimum light-emitting unit, similarly to PDP1-1.
At this time, 1 mm of the information display surface 10b of the blue light emitting phosphor B-3 was used.²The total surface area of the phosphor particles per unit is 86 mm²It became. The green light-emitting phosphor G-3 has a thickness of 87 mm.²88 mm for the red light emitting phosphor R-3²It became. This was designated as PDP of Comparative Example 1.
[0144]
[Evaluation 1]
For the PDP 1-1 and PDP 1-2 manufactured as described above and the PDP manufactured in Comparative Example 1, 1 mm of the information display surface 10b was used.²Phosphor surface area (mm²) And relative luminance of PDP were evaluated. The evaluation was performed as follows.
First, white luminance was measured when an equivalent sustaining voltage (170 V AC voltage) was applied to the discharge electrode 11. Next, relative values of PDP1-1 and PDP1-2 when the white luminance of Comparative Example 1 was set to 100 were determined. The relative value was used to evaluate each PDP. Table 1 shows the results.
[Table 1]

[0145]
As is clear from Table 1, when the relative luminance of Comparative Example 1 was set to 100, the relative luminance of PDP1-1 was 136, and the relative luminance of PDP1-2 was 186. Very high relative luminance values could be obtained.
[0146]
For each of PDP1-1, PDP1-2 and the PDP of the comparative example, the average amount of the phosphor paste per minimum light emitting unit was equal to 0.0635 mg, and the mass of the phosphor contained in the phosphor layer was 0.0254 mg. Is equal to As can be seen from Table 1, the average brightness of the phosphors used is different, as can be seen from Table 1. 1 mm of the information display surface 10b²This is because the total sum of the surface areas of the phosphor particles per unit greatly differs.
[0147]
In Comparative Example 1, a phosphor having an average particle size of 2.10 to 2.16 μm manufactured by a solid-phase synthesis method was used, and thereby, the information display surface 10b was 1 mm thick.²The surface area of the phosphor particles per unit is 86 to 88 mm²It is. On the other hand, the PDP 1-1 uses a phosphor having an average particle size of 0.77 to 0.82 μm manufactured by a liquid phase synthesis method.²Phosphor particles have a surface area of 226 to 240 mm²It is. The PDP1-2 uses a phosphor having an average particle diameter of 0.38 to 0.39 μm, which is also manufactured by a liquid phase synthesis method, so that the information display surface 10b has a thickness of 1 mm.²475-487mm per surface area²It is.
As described above, by making the phosphor constituting the phosphor layer 35 finer and increasing its surface area, even when the amount of the phosphor applied is the same, the ultraviolet light is efficiently received and the amount of emitted light is increased. Can be improved.
[0148]
[Example 2]
Next, a second embodiment will be described. In the second embodiment, the number of phosphor particles per unit area of the information display surface 10b is set to 10 million / mm.²The above PDP2-1 and 80 million pieces / mm²PDP2-2 as described above was manufactured. For comparison with these, the number of phosphor particles per unit area of the information display surface 10b was set to 7,000,000 particles / mm.²Comparative Example 2 was manufactured.
First, the manufacture of the phosphor will be described.
[0149]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-4
Blue light-emitting phosphor B was prepared in the same manner as 1 (1) of Example 1 except that the addition rates of solution B and solution C to solution A in Example 1 (1) were changed to 5.10 cc / min. -4 was prepared.
After firing, the average particle size of the obtained phosphor was determined by observation with an electron microscope, and was found to be 0.78 μm.
[0150]
(2) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-5
Blue light-emitting phosphor B was prepared in the same manner as in Example 1 (2), except that the addition rates of solution B and solution C to solution A in Example 1 (2) were changed to 9.9 cc / min. -5 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.41 μm.
[0151]
(3) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-4
The green light-emitting phosphor was obtained in the same manner as 1 (3) of Example 1 except that the addition rates of the solution B and the solution C to the solution A in Example 1 (3) were changed to 9.72 cc / min. G-4 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.77 μm.
[0152]
(4) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-5
Colloidal silica was used in the same manner as in 1 (4) of Example 1 except that the addition rates of Solution B and Solution C to Solution A were changed to 9.72 cc / min in 1 (4) of Example 1 above. Thus, a green light emitting phosphor G-6 was manufactured.
When the average particle size of the obtained phosphor B-6 was determined by microscopic observation, it was 0.39 μm.
[0153]
(5) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-4
Red light-emitting phosphor in the same manner as 1 (5) of Example 1 except that the addition rates of Solution B and Solution C to Solution A in Example 1 (5) were changed to 10.3 cc / min. R-4 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.76 μm.
[0154]
(6) Red phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-5
Red light-emitting phosphor in the same manner as 1 (6) of Example 1 except that the addition rates of Solution B and Solution C to Solution A in Example 1 (6) were changed to 29.8 cc / min. R-5 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.40 μm.
[0155]
2. Adjustment of phosphor paste
Using the blue light-emitting phosphors B-4, B-5, G-4, G-5, R-4, and R-5 produced above, in the same manner as in Example 1-2, the blue light-emitting phosphor was used. Pastes B-4 and B-5, green light emitting phosphor pastes G-4 and G-5, and red light emitting phosphor pastes R-4 and R-5 were prepared.
[0156]
3. Manufacture of PDP
(1) Production of PDP2-1
PDP2 was prepared in the same manner as 3 (1) of Example 1, except that the blue light-emitting phosphor paste B-4, green light-emitting phosphor paste G-4, and red light-emitting phosphor paste R-4 prepared above were used. -1 was prepared. The phosphor pastes B-4, R-4 and G-4 used at the time of application were 0.0635 mg on average per one minimum light-emitting unit (the amount of the phosphor-containing substance was 0, as in 3 (1) of Example 1). 0.0254 mg).
At this time, the number of phosphors per unit area of the information display surface 10b of the blue light emitting phosphor B-4 is 124 × 10⁶Pieces / mm²It became. The green light-emitting phosphor G-4 was 129 × 10⁶Pieces / mm²134 × 10 for red light-emitting phosphor R-4⁶Pieces / mm²It became.
[0157]
(2) Production of PDP2-2
PDP2 was prepared in the same manner as in 3 (1) of Example 1, except that blue light-emitting phosphor paste B-5, green light-emitting phosphor paste G-5, and red light-emitting phosphor paste R-5 prepared above were used. -2 was prepared. Note that the phosphor pastes B-5, R-5, and G-5 used at the time of application average 0.0635 mg per one minimum light emitting unit, as in 3 (1) of Example 1.
At this time, the number of phosphor particles per unit area of the information display surface 10b of the blue light emitting phosphor B-5 is 854 × 10⁶Pieces / mm²It became. The green light-emitting phosphor G-5 is 993 × 10⁶Pieces / mm²920 × 10 for red light-emitting phosphor R-5⁶Pieces / mm²It became.
[0158]
[Comparative Example 2]
For comparison with the PDPs 2-1 and 2-2 manufactured in Example 2 above, a phosphor was manufactured by a solid-phase synthesis method, and the obtained phosphor was used to obtain information per unit area of the information display surface 10b. 7 × 10 phosphor particles⁶Pieces / mm²A PDP was manufactured as follows.
First, a method of manufacturing the phosphor of each color will be described.
[0159]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-6
A phosphor was manufactured in the same manner as 1 (1) of Comparative Example 1, and a phosphor having an average particle size of 2.17 μm was classified to obtain a blue light-emitting phosphor B-6.
[0160]
(2) Green emitting phosphor (ZnSiO₄: Mn) Production of G-6
A phosphor was produced in the same manner as 1 (2) of Comparative Example 1, and a phosphor having an average particle size of 2.17 μm was classified to obtain a green light-emitting phosphor B-6.
[0161]
(3) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-6
A phosphor was produced in the same manner as in 1 (3) of Comparative Example 1, and a phosphor having an average particle size of 2.08 μm was classified to obtain a red light-emitting phosphor R-6.
[0162]
2. Adjustment of phosphor paste
Except for using the phosphors B-6, G-6, and R-6 obtained above, the respective color light-emitting phosphor pastes B-6, G-6, and R-6 were adjusted in the same manner as in 2 of Example 1. did.
[0163]
3. Manufacture of PDP
PDP similar to 3 (1) of Example 1 except that blue light emitting phosphor paste B-6, green light emitting phosphor paste G-6, and red light emitting phosphor paste R-6 prepared in 2 above were used. Was manufactured. Note that the phosphor pastes B-6, R-6, and G-6 used at the time of coating average 0.0635 mg per one minimum light-emitting unit as in 3 (1) of Example 1.
At this time, the number of phosphor particles per unit area of the information display surface 10b of the blue light emitting phosphor B-6 is 5.7 × 10⁶Pieces / mm²It became. The green light-emitting phosphor G-6 was 5.7 × 10⁶Pieces / mm²6.5 × 10 for red light-emitting phosphor R-6⁶Pieces / mm²It became. This was designated as PDP of Comparative Example 2.
[0164]
[Evaluation 2]
Regarding the PDP2-1 and PDP2-2 produced above and Comparative Example 2, the number of phosphor particles per unit area of the information display surface 10b (pieces / mm)²) And relative luminance of PDP were evaluated in the same manner as in Evaluation 1. Table 2 shows the results.
[Table 2]

[0165]
As is clear from Table 2, when the relative luminance of Comparative Example 2 was set to 100, the relative luminance of PDP2-1 was 132, and the relative luminance of PDP2-2 was 176. Very high relative luminance values could be obtained.
[0166]
For each of PDP2-1, PDP2-2 and PDP of Comparative Example 2, the average amount of the phosphor paste per minimum light emitting unit was equal to 0.0635 mg, and the mass of the phosphor contained in the phosphor layer 35 was 0%. Equivalent to 0.0254 mg. As described above, the average luminance of the phosphors used is different, as is clear from Table 2, in which the relative luminance is remarkably different in spite of the fact that the amount of the phosphors per minimum emission unit is equal. This is because the number of phosphor particles per unit area of the information display surface 10b is greatly different.
[0167]
Comparative Example 2 uses a phosphor having an average particle size of 2.08 to 2.17 μm manufactured by a solid phase synthesis method, and the number of phosphor particles per unit area of the information display surface 10b is 5.7. × 10⁶~ 6.5 × 10⁶Pieces / mm²It is.
On the other hand, the PDP 2-1 uses a phosphor having an average particle diameter of 0.76 to 0.78 μm manufactured by a liquid phase synthesis method, and the number of phosphor particles per unit area of the information display surface 10b. Is 124 × 10⁶~ 134 × 10⁶Pieces / mm², PDP2-2 use phosphor particles having an average particle diameter of 0.39 to 0.41 μm, and the number of phosphor particles per unit area of the information display surface 10b is 854 × 10⁶~ 993 × 10⁶Pieces / mm²It is.
As described above, by finely increasing the number of the phosphor particles constituting the phosphor layer 35 and increasing the number thereof, the ultraviolet rays can be efficiently received, the amount of emitted light is increased, and thereby the relative luminance of the PDP is significantly improved. Can be.
[0168]
[Example 3]
Next, a third embodiment will be described. In Example 3, two PDPs having different total surface areas of the phosphor particles per unit area of the phosphor layer coverable surface in the discharge cell 31 were manufactured. The first PDP 3-1 is 1 mm of the surface capable of covering the phosphor layer.²Total surface area of phosphor particles per unit is 80 mm²It was above. The second PDP 3-2 has a total surface area of the phosphor particles of 150 mm.²It was above. For comparison with these, the total surface area of the phosphor particles per unit area of the phosphor layer-coverable surface was set to 40 mm.²A PDP with less than that was manufactured to be Comparative Example 3.
First, the manufacture of the phosphor will be described.
[0169]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-7
Blue light-emitting phosphor B was prepared in the same manner as 1 (1) of Example 1 except that the addition rates of solution B and solution C to solution A in Example 1 (1) were changed to 5.05 cc / min. -7 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.76 μm.
[0170]
(2) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-8
Blue light-emitting phosphor B was prepared in the same manner as 1 (2) of Example 1 except that the addition rates of solution B and solution C to solution A were changed to 10.5 cc / min in 1 (2) of Example 1. -8 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.41 μm.
[0171]
(3) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-7
In Example 1 (3), the green light-emitting phosphor G- was prepared in the same manner as in Example 1 (3) except that the addition rates of the solution B and the solution C to the solution A were changed to 10.1 cc / min. 7 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.77 μm.
[0172]
(4) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-8
A green color was obtained using colloidal silica in the same manner as in 1 (4) of Example 1 except that the addition rates of Solution B and Solution C to Solution A were changed to 10.1 cc / min in 1 (4) of Example 1 described above. Light-emitting phosphor G-8 was produced.
When the average particle size of the obtained phosphor G-8 was determined by microscopic observation, it was 0.38 μm.
[0173]
(5) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-7
Red light-emitting fluorescence was obtained in the same manner as 1 (5) of Example 1 except that the addition rates of Solution B and Solution C to Solution A in Example 1 (5) were changed to 10.3 cc / min. Body R-7 was prepared.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.76 μm.
[0174]
(6) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-8
Red light-emitting fluorescence was obtained in the same manner as in 1 (6) of Example 1, except that the addition rates of Solution B and Solution C to Solution A in Example 1 (6) were changed to 29.9 cc / min. Body R-8 was prepared.
The average particle size of the obtained phosphor was 0.42 μm as determined by observation with an electron microscope.
[0175]
2. Adjustment of phosphor paste
Using the blue light-emitting phosphors B-7, B-8, G-7, G-8, R-7, and R-8 produced in 1 above, in the same manner as in 2 of Example 1, the blue light-emitting phosphor was used. Body pastes B-7 and B-8, green light emitting phosphor pastes G-7 and G-8, and red light emitting phosphor pastes R-7 and R-8 were respectively adjusted.
[0176]
3. Manufacture of PDP
(1) Production of PDP3-1
PDP3 was prepared in the same manner as 3 (1) of Example 1, except that the blue light-emitting phosphor paste B-7, green light-emitting phosphor paste G-7, and red light-emitting phosphor paste R-7 prepared above were used. -1 was prepared. The phosphor pastes B-7, R-7, and G-7 used at the time of coating were 0.0635 mg on average per one minimum light-emitting unit (the amount of the phosphor-containing substance was 0, as in 3 (1) of Example 1). 0.0254 mg).
At this time, 1 mm of the surface of the blue light emitting phosphor B-7 capable of covering the phosphor layer was used.²The total surface area of the phosphor particles per unit is 88 mm²It became. The green light-emitting phosphor G-7 has a thickness of 87 mm.²88 mm for the red light emitting phosphor R-7²It became.
[0177]
(2) Production of PDP3-2
Except that the blue light emitting phosphor paste B-8, green light emitting phosphor paste G-8, and red light emitting phosphor paste R-8 prepared above were used, a method similar to (1) of Example 1-3 was used. PDP3-2 was produced. The phosphor pastes B-8, R-8, and G-8 used in the application were 0.0635 mg on average per one minimum light-emitting unit, as in (1) of 3 of Example 1.
At this time, 1 mm of the surface of the blue light-emitting phosphor B-8 that can be covered with the phosphor layer was used.²The total surface area of the phosphor particles per unit is 185 mm²It became. In addition, the green light-emitting phosphor G-8 is 176 mm²159 mm for the red light-emitting phosphor R-8²It became.
[0178]
[Comparative Example 3]
For comparison with the above-mentioned PDP3-1 and PDP3-2, a phosphor was produced by a solid phase synthesis method, and a phosphor layer-coverable surface of 1 mm was obtained using the obtained phosphor.²Total surface area of phosphor particles per unit is 40 mm²A PDP was manufactured as follows.
First, a method of manufacturing the phosphor of each color will be described.
[0179]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-9
A phosphor was manufactured in the same manner as 1 (1) of Comparative Example 1, and a phosphor having an average particle size of 2.12 μm was classified to obtain a blue light-emitting phosphor B-9.
[0180]
(2) Green emitting phosphor (ZnSiO₄: Mn) Production of G-9
A phosphor was produced in the same manner as 1 (2) of Comparative Example 1, and a phosphor having an average particle size of 2.10 μm was classified to obtain a green light-emitting phosphor G-9.
[0181]
(3) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺)Manufacturing of
A phosphor was produced in the same manner as 1 (3) of Comparative Example 1, and a phosphor having an average particle size of 2.08 μm was classified to obtain a red light-emitting phosphor R-9.
[0182]
2. Adjustment of phosphor paste
Except for using the respective color light emitting phosphors B-9, G-9 and R-9 obtained above, the respective color light emitting phosphor pastes B-9, G-9 and R-9 were prepared in the same manner as in Example 1-2. Each was adjusted.
[0183]
3. Manufacture of PDP
PDP similar to 3 (1) of Example 1 except that the blue light emitting phosphor paste B-9, the green light emitting phosphor paste G-9, and the red light emitting phosphor paste R-9 adjusted in the above 2 were used. Was manufactured. Note that the phosphor pastes B-9, R-9, and G-9 used at the time of application average 0.0635 mg per one minimum light-emitting unit, as in 3 (1) of Example 1.
At this time, 1 mm of the surface of the blue light emitting phosphor B-9 capable of covering the phosphor layer was used.²The total surface area of the phosphor particles per unit is 31 mm²It became. The green light-emitting phosphor G-9 is 32 mm²32 mm for the red light emitting phosphor R-9²It became. This was designated as PDP of Comparative Example 3.
[0184]
[Evaluation 3]
Regarding the PDP3-1 and PDP3-2 produced in the above and Comparative Example 3, the phosphor layer-coverable surface 1 mm²Total surface area of phosphor particles per unit (mm²) And relative luminance of PDP were evaluated in the same manner as in Evaluation 1. Table 3 shows the results.
[Table 3]

[0185]
As is clear from Table 3, when the relative luminance of Comparative Example 3 was set to 100, the relative luminance of PDP 3-1 was 141, and the relative luminance of PDP 3-2 was 195. Very high relative luminance values could be obtained.
[0186]
For each of PDP3-1, PDP3-2, and PDP of Comparative Example 3, the average amount of the phosphor paste per the minimum emission unit was equal to 0.0635 mg, and the amount of the phosphor applied in the phosphor layer 35 was 0.0254 mg. Is equal to As can be seen from Table 3, the average particle size of the phosphors used is different because the relative luminance is remarkably different in spite of the fact that the amount of the phosphors per minimum light emission unit is equal. 1mm of the phosphor layer coverable surface²This is because the total sum of the surface areas of the phosphor particles per unit greatly differs.
[0187]
In Comparative Example 3, a phosphor having an average particle diameter of 2.08 to 2.12 μm manufactured by a solid-phase synthesis method was used, and thereby, the phosphor layer-coverable surface was 1 mm.²The total of the surface area of the phosphor particles per unit is 31 to 32 mm²It is. In contrast, PDP 3-1 uses a phosphor having an average particle size of 0.76 to 0.77 μm manufactured by a liquid phase synthesis method, so that the total surface area is 87 to 88 mm.²It is. PDP3-2 uses a phosphor having an average particle size of 0.36 to 0.42 μm, which is also manufactured by a liquid phase synthesis method, so that the total surface area is 159 to 185 mm.²It is. In this way, even when the phosphor loadings are equal, fine phosphors are used, thereby efficiently increasing the total surface area of the phosphor particles per unit area of the phosphor layer-coverable surface, thereby improving the efficiency. By receiving ultraviolet rays, the relative luminance can be significantly improved.
[0188]
[Example 4]
Next, a fourth embodiment will be described. In Example 4, the number of phosphor particles per unit area of the phosphor layer-coverable surface was 300,000 / mm.²The above PDP4-1 and 3 million pieces / mm²The PDP4-2 described above was manufactured. For comparison with these, the number of phosphor particles per unit area of the phosphor layer-coverable surface was set to 30,000 / mm.²Comparative Example 4 was manufactured.
First, the manufacture of the phosphor will be described.
[0189]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-10
It was manufactured in the same manner as 1 (1) of Example 1 except that the addition rates of the solution B and the solution C to the solution A were changed to 4.90 cc / min.
The average particle size of the obtained phosphor was 0.85 μm as determined by observation with an electron microscope.
[0190]
(2) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-11
Blue light-emitting phosphor was prepared in the same manner as 1 (2) of Example 1 except that the addition rates of solution B and solution C to solution A in Example 1 (2) were changed to 10.6 cc / min. B-11 was produced.
The average particle size of the obtained phosphor was determined by observation with an electron microscope and found to be 0.36 μm.
[0191]
(3) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-10
The green light-emitting phosphor G was obtained in the same manner as 1 (3) of Example 1 except that the addition rates of the solution B and the solution C to the solution A were changed to 9.50 cc / min in 1 (3) of Example 1 described above. -10 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.84 μm.
[0192]
(4) Green light-emitting phosphor (Zn₂SiO₄: Mn) Production of G-11
In Example 1 (4), colloidal silica was used in the same manner as in Example 1 (4), except that the addition rates of the solution B and the solution C to the solution A were 9.50 cc / min. A green light emitting phosphor G-11 was manufactured.
When the average particle size of the obtained phosphor G-11 was determined by microscopic observation, it was 0.39 μm.
[0193]
(5) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-10
Red light-emitting phosphor in the same manner as 1 (5) of Example 1 except that the addition rates of Solution B and Solution C to Solution A in Example 1 (5) were changed to 10.7 cc / min. R-10 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.75 μm.
[0194]
(6) Red phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-11
Red light-emitting phosphor in the same manner as 1 (6) of Example 1 except that the addition rates of Solution B and Solution C to Solution A in Example 1 (6) were changed to 29.9 cc / min. R-11 was produced.
When the average particle size of the obtained phosphor was determined by observation with an electron microscope, it was 0.41 μm.
[0195]
2. Adjustment of phosphor paste
Using the blue light emitting phosphors B-10, B-11, G-10, G-11, R-10, and R-11 produced in 1 above, in the same manner as in 2 of Example 1, the blue light emitting phosphor was used. Body pastes B-10 and B-11, green light emitting phosphor pastes G-10 and G-11, and red light emitting phosphor pastes R-10 and R-10 were respectively adjusted.
[0196]
3. Manufacture of PDP
(1) Production of PDP4-1
Except that the blue light-emitting phosphor paste B-10, the green light-emitting phosphor paste G-10, and the red light-emitting phosphor paste R-10 prepared in the above 2 were used, a method similar to 3 (1) of Example 1 was used. PDP4-1 was produced. The phosphor pastes B-10, R-10, and G-10 used at the time of application were 0.0635 mg on average per one minimum light-emitting unit (the phosphor-containing amount was 0, as in 3 (1) of Example 1). 0.0254 mg).
At this time, the number of phosphor particles per unit area of the phosphor layer coverable surface of the blue light emitting phosphor B-10 is 34 × 10⁶Pieces / mm²It became. Also, for the green light-emitting phosphor G-10, 35 × 10⁶Pieces / mm², 50 × 10 for the red light emitting phosphor R-10⁶Pieces / mm²It became.
[0197]
(2) Production of PDP4-2
PDP4 was prepared in the same manner as 3 (1) of Example 1, except that the blue light-emitting phosphor paste B-11, green light-emitting phosphor paste G-11, and red light-emitting phosphor paste R-11 prepared above were used. -2 was prepared. Note that the phosphor pastes B-11, R-11, and G-11 used at the time of application are, on average, 0.0635 mg per one minimum light emitting unit, as in 3 (1) of Example 1.
At this time, the number of phosphor particles per unit area of the phosphor layer coverable surface of the blue light emitting phosphor B-11 is 455 × 10⁶Pieces / mm²It became. Further, for the green light emitting phosphor G-11, 357 × 10⁶Pieces / mm²308 × 10 for red light-emitting phosphor R-11⁶Pieces / mm²It became.
[0198]
[Comparative Example 4]
For comparison with the above Example 4, a phosphor was produced by a solid phase synthesis method, and the number of phosphor particles per unit area of the phosphor layer-coverable surface was 3 × using the obtained phosphor. 10⁶Pieces / mm²A PDP was manufactured as follows.
First, a method of manufacturing the phosphor of each color will be described.
[0199]
1. Manufacture of phosphor
(1) Blue light-emitting phosphor (BaMgAl₁₀O₁₇: Eu²⁺) Production of B-12
A phosphor was produced in the same manner as in 1 (1) of Comparative Example 1, and particles having an average particle size of 2.05 μm were classified to obtain a blue light-emitting phosphor B-12.
[0200]
(2) Green emitting phosphor (ZnSiO₄: Mn) Production of G-12
A phosphor was produced in the same manner as in 1 (2) of Comparative Example 1, and particles having an average particle size of 2.07 μm were classified to obtain a green light-emitting phosphor G-12.
[0201]
(3) Red light-emitting phosphor ((Y, Gd) BO₃: Eu³⁺) Production of R-12
A phosphor was produced in the same manner as 1 (3) of Comparative Example 1, and particles having an average particle size of 2.11 μm were classified to obtain a red light-emitting phosphor R-12.
[0202]
2. Adjustment of phosphor paste
Except for using the phosphors B-12, G-12, and R-12 obtained above, the respective color light-emitting phosphor pastes B-12, G-12, and R-12 were adjusted in the same manner as in 2 of Example 1. did.
[0203]
3. Manufacture of PDP
Except that the blue light-emitting phosphor paste B-12, the green light-emitting phosphor paste G-12, and the red light-emitting phosphor paste R-12 adjusted in the above 2 were used, the same as (1) of Example 1-3 was used. PDP was manufactured. The phosphor pastes B-12, R-12, and G-12 used in the application were 0.0635 mg on average per one minimum light-emitting unit, as in 3 (1) of Example 1.
At this time, the number of the phosphor particles per unit area of the phosphor layer coverable surface of the blue light emitting phosphor B-12 is 2.4 × 10⁶Pieces / mm²It became. The green light-emitting phosphor G-12 was 2.3 × 10⁶Pieces / mm²And 2.2 × 10 for red light-emitting phosphor R-12.⁶Pieces / mm²It became. This was designated as PDP of Comparative Example 4.
[0204]
[Evaluation 4]
Regarding the PDP4-1 and PDP4-2 produced above and Comparative Example 4, the number of phosphor particles per unit area of the phosphor layer-coverable surface (pieces / mm)²) And relative luminance of PDP were evaluated. The evaluation was performed in the same manner as the evaluation I described above, and comparison was made based on relative values. Table 4 shows the results.
[Table 4]

[0205]
As is clear from Table 4, when the relative luminance of Comparative Example 4 is set to 100, the relative luminance of PDP4-1 is 127, the relative luminance of PDP4-2 is 167, and the PDP of the present invention is different from Comparative Example 4. Very high relative luminance values could be obtained.
[0206]
For each of PDP4-1, PDP4-2 and PDP of Comparative Example 4, the amount of the phosphor paste per minimum emission unit was equal to 0.0635 mg on average, and the mass of the phosphor contained in the phosphor layer was equal, 0.0254 mg. As can be seen from Table 4, the relative luminance is remarkably different in spite of the fact that the amount of the fluorescent substance per minimum light emitting unit is equal. This is because the number of phosphor particles per unit area of the body layer coverable surface is greatly different.
[0207]
In Comparative Example 4, a phosphor having an average particle size of 2.05 to 2.11 μm manufactured by a solid phase synthesis method was used, whereby the number of phosphor particles per unit area of the phosphor layer-coverable surface was reduced. 2.2 × 10⁶~ 2.4 × 10⁶Pieces / mm²It is.
On the other hand, PDP4-1 uses a phosphor having an average particle diameter of 0.75 to 0.85 μm manufactured by a liquid phase synthesis method, whereby the fluorescence per unit area of the phosphor layer coverable surface is determined. 34 × 10 body particles⁶~ 50 × 10⁶Pieces / mm²It is. PDP4-2 uses a phosphor having an average particle diameter of 0.36 to 0.41 μm, which is also produced by a liquid phase synthesis method, so that the number of phosphor particles is 308 × 10⁶~ 455 × 10⁶Pieces / mm²It is. As described above, by increasing the number of phosphors constituting the phosphor layer, even when the amounts of the phosphors are equal, ultraviolet rays can be efficiently received, and the relative luminance can be improved.
【The invention's effect】
According to the present invention, by increasing the total surface area of the phosphor particles constituting the phosphor layer or the number of the phosphor particles as compared with the related art, it is possible to efficiently receive ultraviolet rays and improve luminous efficiency. Can be. Thereby, high luminance can be achieved even with a high-definition PDP without increasing the amount of phosphor applied. In addition, by producing a phosphor by a liquid phase synthesis method, a fine-grain phosphor having high purity stoichiometrically can be obtained. Thereby, the ratio of the volume contributing to light emission in the phosphor particles can be increased, and a phosphor having higher luminous efficiency than before can be obtained. Therefore, by using the phosphor synthesized by the liquid phase synthesis method, the brightness of the PDP can be further improved.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a plasma display panel according to the present invention.
FIG. 2 is a schematic plan view showing an arrangement of electrodes provided on the plasma display panel shown in FIG.
FIG. 3 is a schematic plan view showing a lattice type cell structure as another example of the structure of the discharge cells provided in the plasma display panel according to the present invention.
FIG. 4 is a schematic plan view showing a honeycomb cell structure as another example of the structure of the discharge cells provided in the plasma display panel according to the present invention.
[Explanation of symbols]
1 Plasma display panel
10mm front side board, board
10a Information display surface
20 back plate side substrate, (one) substrate
30, 40, 50 ° partition
30a Partition surface
31, 41, 51 ° discharge cell
31a One substrate surface
35 ° phosphor layer

Claims (5)

A front-side substrate having an information display surface, a rear-side substrate disposed to face the front-side substrate at a predetermined interval, and a partition provided between these substrates to partition a space between the substrates into a plurality of partitions; A discharge cell formed by being surrounded by the partition wall and the substrate, and a phosphor layer provided inside the discharge cell,
By performing a plasma discharge in the discharge cell, to generate visible light from the phosphor layer, the plasma display panel performs information display by projecting the visible light to the information display surface,
The sum of the surface area of the phosphor particles constituting the phosphor layer, the per information display screen 1mm per ^2, 100 mm ² or more, the plasma display panel, characterized in that it is 3,000 mm ² or less. A front-side substrate having an information display surface, a rear-side substrate disposed to face the front-side substrate at a predetermined interval, and a partition provided between these substrates to partition a space between the substrates into a plurality of partitions; A discharge cell formed by being surrounded by the partition wall and the substrate, and a phosphor layer provided inside the discharge cell,
By performing a plasma discharge in the discharge cell, to generate visible light from the phosphor layer, the plasma display panel performs information display by projecting the visible light to the information display surface,
The number of phosphor particles constituting the phosphor layer, per unit area of the information display screen 700 thousands / mm ² or more, the plasma display panel, characterized in that 300 billion / mm ² or less. Two substrates disposed facing each other at a predetermined interval, a partition wall provided between the substrates to partition a space between the substrates into a plurality, a discharge cell formed by being surrounded by the partition walls and the substrate, A plasma display panel comprising a phosphor layer provided inside the cell,
When the surface of the partition wall and the surface of one of the substrates facing the inside of the discharge cell and the phosphor layer can be coated,
The sum of the surface area of the phosphor particles constituting the phosphor layer, the per phosphor layer coatable surface 1mm per ^2, 40 mm ² or more, the plasma display panel, characterized in that it is 600 mm ² or less. Two substrates disposed facing each other at a predetermined interval, a partition wall provided between the substrates to partition a space between the substrates into a plurality, a discharge cell formed by being surrounded by the partition walls and the substrate, A plasma display panel comprising a phosphor layer provided inside the cell,
When the surface of the partition wall and the surface of one of the substrates facing the inside of the discharge cell and the phosphor layer can be coated,
The plasma number of phosphor particles constituting the phosphor layer, the per unit area of the phosphor layer coatable surface, that 3 million / mm ² or more, characterized in that 50 billion / mm ² or less Display panel. The plasma display panel according to any one of claims 1 to 4,
A plasma display panel, wherein the phosphor particles are manufactured by a liquid phase synthesis method in which a phosphor material is reacted in a liquid phase.

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