JP3979813B2 - Method for manufacturing substrate for plasma display panel - Google Patents

Description

【００９０】
表１より、比較例１及び２のように、現行の絶縁膜形成用塗料を構成する溶媒では、Ａｇ、Ｃｕ、Ｃｒのような金属化合物には濡れ性が良いが、ＩＴＯのようなセラミックス化合物ではα−テルピネオールは濡れ性がやや悪く、ガラス基板に対してはもっと濡れが悪かった。これは、ＵＶ洗浄を施した基板に対しても同様の結果であった。
【００９１】
一方、実施例１〜４の溶媒は、ガラス基板、金属化合物、セラミックス化合物のいずれに対しても濡れ性が優れており、ＵＶ洗浄後も同様であった。
【００９２】
実施例５の溶媒は、基板上の測定箇所によりやや接触角が変動する結果となったが、ＵＶ洗浄後の基板上ではどの箇所においても良好な濡れ性を示していた。
【００９３】
実施例６及び７の溶媒は、未処理基板上において、ガラス基板、金属化合物、セラミックス化合物に対して濡れ性が悪い場合が見られたが、ＵＶ洗浄を基板に施すことにより、基板への濡れ性が大きく良化し、バラツキも見られなかった。
【００９４】
（絶縁膜形成用塗料の調製）
また、上記の接触角測定で用いた有機溶媒を１００％とする溶媒を用いて、以下の組成比、方法にて絶縁膜形成用塗料を作製した。エチルセルロース（ダウ・ケミカル製、商品名「エトセルＳＴＤ−７」、重合度６０，０００）を１０％含有したビヒクル（樹脂を溶解した溶媒）２００ｇと、ガラス粉末として平均粒径３μｍの酸化鉛系ガラスフリット（組成系：ＰｂＯ−ＭｇＯ−Ｂ₂Ｏ₃−ＳｉＯ₂）３００ｇを、混合・予備混練し、３本ロールで混練して絶縁膜形成用塗料とした。
【００９５】
（耐電圧の評価）
この絶縁膜形成用塗料を施工して得られた誘電体層の絶縁性（耐電圧）を、以下の方法にて測定した。
【００９６】
ガラス基板（ＰＤ−２００）上に焼成タイプのＡｇペーストを印刷し、５９０℃で焼成して下部電極を形成した。この上に本発明の絶縁膜形成用塗料を、下部電極の端部が露出する形で印刷し、５９０℃で焼成した。なお、焼成後の誘電体層膜厚が３０μｍとなるように、印刷条件を調整した。さらにこの上に熱硬化タイプのＡｇペーストを下部電極面積に収まる形で塗布し、１５０℃で加熱して上部電極を形成した。上部電極と下部電極の端部に相反対するような形で接点をとり、耐電圧測定器（菊水電子製）で０．５ｍＡの電力がリークした時点を絶縁破壊として、耐電圧値を測定した。同様にして、Ｃｒ−Ｃｕ−Ｃｒ電極上に形成した誘電体層の耐電圧も測定した。
【００９７】
また、Ａｇ電極（下部電極）の下地電極として、スパッタ法によるパターニングでＩＴＯ電極を厚さ２μｍで作製したガラス基板上（ＰＤ−２００）に、上述の方法でＡｇ電極（下部電極）を形成したものも用意した。そして、上述と同様に本発明の絶縁膜形成用塗料を用いて誘電体層を形成し、そして熱硬化タイプのＡｇペーストにより上部電極を形成した基板について、同様にして耐電圧を測定した。同様にして、Ｃｒ−Ｃｕ−Ｃｒ電極上に形成した誘電体層の耐電圧も測定した。
【００９８】
以上の測定結果を、表１にまとめて示した。
【００９９】
表１より明らかなように、実施例１〜４の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、良好な耐電圧特性を有していた。
【０１００】
実施例５の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、基板未処理の状態においても実用するに十分な耐電圧特性を有する耐電圧特性を有していたが、ＵＶ洗浄を施すことにより、より一層耐電圧特性が向上した誘電体層となっていた。
【０１０１】
実施例６及び７の絶縁膜形成用塗料から作製された誘電体層は、未処理の基板上に作製した場合は耐電圧特性が不十分であったが、ＵＶ洗浄を施すことにより、実用するに充分な耐電圧特性を有する誘電体層となっていた。
【０１０２】
一方、比較例１及び２の絶縁膜形成用塗料から作製された誘電体層は、いずれもボイドやピンホールが発生し、耐電圧特性も、実施例の耐電圧特性と比べてやや劣る結果であった。
【０１０３】
（アドレス電極保護効果の評価）
次に、アドレス電極保護膜としての効果について評価した。ガラス基板（ＰＤ−２００）上に焼成タイプのＡｇペーストを印刷し、５９０℃で焼成して下部電極を形成した。この上に本発明の絶縁膜形成用塗料を、全面を被覆する形で焼成後膜厚が３μｍとなるように印刷し、５９０℃で焼成した。得られた絶縁膜は１回の塗布で形成されたものである。この結果を表１に示す。
【０１０４】
なお、アドレス電極保護効果は、以下の基準で評価した。
○：ボイドやピンホールが発生しない
×：ボイドやピンホールが発生する
【０１０５】
表１より明らかなように、実施例１〜５の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１０６】
実施例６及び７の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、未処理基板ではボイドやピンホールが発生し、保護膜として不十分であったが、ＵＶ洗浄済基板ではボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１０７】
一方、比較例１及び２の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、保護膜としては不十分であった。
【０１０８】
（隔壁としての評価）
ガラス基板（ＰＤ−２００）上に、本発明の絶縁膜形成用塗料を焼成後の膜厚が２００μｍとなるように塗布して乾燥し、パターニングされた保護膜で被覆した後、サンドブラスト法で隔壁パターンを形成した。そして、保護膜を除去した後、５９０℃にて焼成して隔壁を形成した。その評価結果について表１に示す。
【０１０９】
なお、隔壁は、以下の基準で評価した。
○：ボイドやピンホールの発生、隔壁の剥がれがない
△：ボイドやピンホールは発生しないが、隔壁が剥がれる
×：ボイドやピンホールが発生し、隔壁が剥がれる
【０１１０】
表１より明らかなように、実施例１〜４の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールなどの欠陥が無く、隔壁の一部がガラス基板から剥がれたりすることは無かった。
【０１１１】
実施例５の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールの発生は無かったが、隔壁の剥がれが発生する場合もあった。しかし、ＵＶ洗浄を行うことで隔壁の剥がれの発生も抑制された。
【０１１２】
実施例６及び７の絶縁膜形成用塗料から作製された隔壁は、未処理基板ではボイドやピンホールの発生、隔壁の剥がれなどが生じる場合があったが、ＵＶ洗浄済基板ではボイドやピンホールの発生、隔壁の剥がれなどは起こらず、隔壁として十分であった。
【０１１３】
一方、比較例１及び２の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、隔壁が形成されない場所が発生したり、隔壁の一部が剥がれたりした。
【０１１４】
【表２】

【０１１５】
【表３】

【０１１６】
（実施例８〜１１及び比較例３、４）
有機溶媒を表２に示した比率で混合して作製した各混合溶媒について、実施例１〜７及び比較例１、２と同様にして濡れ性の評価を行った。ただし、ＤＣｒ：ジエチルカルビトール、ＣｒＡｃ：カルビトールアセテート、ＢＣＡ：ブチルカルビトールアセテートである。また、同様に絶縁膜形成用塗料を作製し、その耐電圧、アドレス電極保護効果、そして隔壁としての効果を評価した。これらの結果を表３に示す。
【０１１７】
表３より明らかなように、実施例８及び９の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、良好な耐電圧特性を有していた。
【０１１８】
実施例１０及び１１の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、基板未処理の状態においても実用するに十分な耐電圧特性を有する耐電圧特性を有していたが、ＵＶ洗浄を施すことにより、より一層耐電圧特性が向上した誘電体層となっていた。
【０１１９】
比較例３及び４の絶縁膜形成用塗料から作製された誘電体層は、いずれもボイドやピンホールが発生し、耐電圧特性もやや劣る結果であった。
【０１２０】
また、アドレス電極保護膜としては、表３より明らかなように、実施例８〜１１の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１２１】
一方、比較例３及び４の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、保護膜としては不十分であった。
【０１２２】
また、隔壁としては、表３より明らかなように、実施例８及び実施例９の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールなどの欠陥が無く、隔壁の一部がガラス基板から剥がれたりすることは無かった。実施例１０及び１１の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールの発生は無かったが、隔壁の剥がれが発生する場合もあった。しかし、ＵＶ洗浄を行うことで隔壁の剥がれの発生も抑制された。
【０１２３】
一方、比較例３及び４の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、隔壁が形成されない場所が発生したり、隔壁の一部が剥がれたりした。
【０１２４】
【表４】

【０１２５】
（実施例１２〜１７）
有機溶媒を（表４）に示した比率で混合して作製した各混合溶媒について、実施例１〜１１及び比較例１〜４と同様にして濡れ性の評価を行った。ただし、ＤＥＣｅ：ジエチルセロソルブ、ＤＣｒ：ジエチルカルビトール、ＤＰｎＰ：ジプロピレングリコール−ｎ−プロピルエーテル、ＴＰＭ：トリプロピレングリコールモノメチルエーテルである。また、同様に絶縁膜形成用塗料を作製し、その耐電圧、アドレス電極保護効果、そして隔壁としての効果を評価した。これらの結果を表５に示す。
【０１２６】
【表５】

【０１２７】
表５より明らかなように、実施例１２〜１７の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、良好な耐電圧特性を有していた。また、それらは溶媒が単成分である実施例１〜７、及び濡れ性に劣る溶媒を含んだ実施例８〜１１よりも耐電圧特性が向上した。
【０１２８】
また、アドレス電極保護膜としては、表５より明らかなように、実施例１２〜１７の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１２９】
また、表５より明らかなように、実施例１２〜１７の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールなどの欠陥が無く、隔壁の一部がガラス基板から剥がれたりすることは無く、隔壁として十分であった。
【０１３０】
（実施例１８〜２４及び比較例５、６）
ガラス基板が、青板ガラス（＃００５０：松浪硝子工業製）の場合について、以下に示す有機溶媒の接触角を、実施例１〜７及び比較例１、２と同様にして試験した。青板ガラスに対する各溶媒の接触角を表６に示す。
・実施例１８：ジエチルカルビトール（ジエチレングリコールジエチルエーテル）
・実施例１９：ジプロピレングリコール−ｎ−プロピルエーテル
・実施例２０：トリプロピレングリコールモノメチルエーテル
・実施例２１：ジエチルセロソルブ（エチレングリコールジエチルエーテル）
・実施例２２：カルビトールアセテート（ジエチレングリコールモノエチルエーテルアセテート）
・実施例２３：ジブチルセロソルブ（エチレングリコールジブチルエーテル）
・実施例２４：プロピレングリコールジアセテート
・比較例５ ：α−テルピネオール
・比較例６ ：ブチルカルビトールアセテート（ジエチレングリコールモノ−ｎ−ブチルエーテルアセテート）
また、同様に絶縁膜形成用塗料を作製し、ガラス基板（ＰＤ−２００）の代わりに青板ガラス（＃００５０）を用いた以外は、実施例１〜７及び比較例１、２と同様にして、その耐電圧、アドレス電極保護効果、そして隔壁としての効果を評価した。これらの結果を表６に示す。
【０１３１】
【表６】

【０１３２】
表６より、比較例５及び６のように、現行の絶縁膜形成用塗料を構成する溶媒は、ガラス基板に対する濡れが悪く、ＵＶ洗浄を施した基板に対しても同様の結果であった。
【０１３３】
実施例１８〜２１の溶媒は、ガラス基板に対して濡れ性が優れており、ＵＶ洗浄後も同様であった。
【０１３４】
実施例２２の溶媒は、基板上の測定箇所によりやや接触角が変動する結果となっていたが、ＵＶ洗浄後の基板上ではどの箇所においても良好な濡れ性を示していた。
【０１３５】
実施例２３及び２４の溶媒は、未処理基板上においてガラス基板に対して濡れ性が悪い場合が見られたが、ＵＶ洗浄を基板に施すことにより、基板への濡れ性が大きく良化し、バラツキも見られなかった。
【０１３６】
また、表６より明らかなように、実施例１８〜２１の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、良好な耐電圧特性を有していた。
【０１３７】
実施例２２の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、基板未処理の状態においても実用するに十分な耐電圧特性を有する耐電圧特性を有していたが、ＵＶ洗浄を施すことにより、より一層耐電圧特性が向上した誘電体層となっていた。
【０１３８】
実施例２３及び２４の絶縁膜形成用塗料から作製された誘電体層は、未処理の基板上に作製した場合は耐電圧特性が不十分であったが、ＵＶ洗浄を施すことにより、実用するに充分な耐電圧特性を有する誘電体層となっていた。
【０１３９】
一方、比較例５及び６の絶縁膜形成用塗料から作製された誘電体層は、いずれもボイドやピンホールが発生し、耐電圧特性もやや劣る結果であった。
【０１４０】
また、表６より明らかなように、実施例１８〜２２の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１４１】
実施例２３及び２４の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、未処理基板ではボイドやピンホールが発生し、保護膜として不十分であったが、ＵＶ洗浄済基板ではボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１４２】
一方、比較例５及び６の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、保護膜としては不十分であった。
【０１４３】
また、表６より明らかなように、実施例１８〜２１縁膜形成用塗料から作製された隔壁は、ボイドやピンホールなどの欠陥が無く、隔壁の一部がガラス基板から剥がれたりすることは無かった。
【０１４４】
実施例２２の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールの発生は無かったが、隔壁の剥がれが発生する場合もあった。しかし、ＵＶ洗浄を行うことで隔壁の剥がれの発生も抑制された。
【０１４５】
実施例２３及び２４の絶縁膜形成用塗料から作製された隔壁は、未処理基板ではボイドやピンホールの発生、隔壁の剥がれなどが生じる場合があったが、ＵＶ洗浄済基板ではボイドやピンホールの発生、隔壁の剥がれなどは起こらず、隔壁として十分であった。
【０１４６】
一方、比較例５及び６の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、隔壁が形成されない場所が発生したり、隔壁の一部が剥がれたりした。
【０１４７】
（実施例２５〜２８及び比較例７、８）
有機溶媒を表２に示した比率で混合して作製した各混合溶媒について、実施例１〜７及び比較例１、２と同様にして、青板ガラス（＃００５０）に対する濡れ性の評価を行った。ただし、ＤＣｒ：ジエチルカルビトール、ＣｒＡｃ：カルビトールアセテート、ＢＣＡ：ブチルカルビトールアセテートであり、実施例２５、２６、２７、２８はそれぞれ実施例８、９、１０、１１と同組成の溶媒とし、比較例７及び８はそれぞれ比較例３及び４と同組成の溶媒を用いた。また、同様に絶縁膜形成用塗料を作製し、実施例１８〜２４及び比較例５、６と同様に青板ガラスに対して絶縁膜を形成し、その耐電圧、アドレス電極保護効果、そして隔壁としての効果を評価した。これらの結果を表７に示す。
【０１４８】
【表７】

【０１４９】
表７より明らかなように、実施例２５及び２６の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、良好な耐電圧特性を有していた。
【０１５０】
実施例２７及び２８の絶縁膜形成用塗料から作製された誘電体層は、ボイドやピンホールなどが無く、基板未処理の状態においても実用するに十分な耐電圧特性を有する耐電圧特性を有していたが、ＵＶ洗浄を施すことにより、より一層耐電圧特性が向上した誘電体層となっていた。
【０１５１】
比較例７及び８の絶縁膜形成用塗料から作製された誘電体層は、いずれもボイドやピンホールが発生し、耐電圧特性もやや劣る結果であった。
【０１５２】
また、アドレス電極保護膜としては、表７より明らかなように、実施例２５〜２８の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールなどの欠陥が無く、保護膜として十分な効果を示していた。
【０１５３】
一方、比較例７及び８の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、保護膜としては不十分であった。
【０１５４】
また、隔壁としては、表７より明らかなように、実施例２５及び実施例２６の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールなどの欠陥が無く、隔壁の一部がガラス基板から剥がれたりすることは無かった。実施例２７及び２８の絶縁膜形成用塗料から作製された隔壁は、ボイドやピンホールの発生は無かったが、隔壁の剥がれが発生する場合もあった。しかし、ＵＶ洗浄を行うことで隔壁の剥がれの発生も抑制された。
【０１５５】
一方、比較例７及び８の絶縁膜形成用塗料から作製されたアドレス電極保護膜は、ボイドやピンホールが発生し、隔壁が形成されない場所が発生したり、隔壁の一部が剥がれたりした。
【０１５６】
【発明の効果】
以上説明したとおり、本発明の絶縁膜形成用塗料は、ガラス化合物（ガラス基板など）、金属化合物（Ａｇ電極など）、セラミックス化合物（ＩＴＯ膜など）のいずれとも濡れ性が良く、これらの各無機材料との接触角が５°未満である有機溶媒を主溶媒とし、全溶媒中におけるその存在比を５０重量％以上とすることにより、ガラス基板、Ａｇ電極、ＩＴＯ膜のいずれとも濡れ性がよく、その結果、ハジキや空隙発生が起こらない絶縁膜形成用塗料とすることが出来る。したがって、本発明の絶縁膜形成用塗料を用いて絶縁層を形成することにより、ボイドやピンホールの発生がなく、耐電圧に優れた、プラズマディスプレイパネルなどを提供することができる。
【０１５７】
また、本発明の絶縁膜形成用塗料を用いて、プラズマディスプレイパネルの表面ガラス基板の誘電体層、または背面ガラス基板の誘電体層、または背面ガラス基板の隔壁を形成することにより、高歩留まりでプラズマディスプレイパネルを得ることが出来る。
【図面の簡単な説明】
【図１】プラズマディスプレイパネルの構造を示す断面図である。
【図２】接触角の測定方法の説明図である。
【符号の説明】
１ 表面ガラス基板
２ 背面ガラス基板
３ 表示電極
４ 透明電極
５ アドレス電極
６ 蛍光体
７ 表面誘電体層
８ 背面誘電体層
９ 隔壁
１０ ＭｇＯ膜[0001]
[Field of the Invention]
The present invention relates to an insulating film forming paint used for an insulating film formed in a plasma display panel, a plasma addressed liquid crystal display or an image forming apparatus using an electron-emitting device, and an address electrode protection on a back plate using the same. The present invention relates to a plasma display panel in which a film, a partition, or a dielectric layer on a surface plate is formed.
[0002]
[Prior art]
As an image forming apparatus that replaces a conventional heavy and large cathode ray tube, there is an increasing demand for a thin and light flat display, so-called flat panel display (FPD). A typical example of an FPD is a liquid crystal display (LCD), but problems remain such as a dark image, a narrow viewing angle, and difficulty in increasing the area. Therefore, in recent years, plasma display panels (PDP) and image forming devices using electron-emitting devices have attracted attention, and their demand is increasing because they can be made higher in definition and larger than LCDs. ing.
[0003]
FIG. 1 shows an example of a structural diagram (cross-sectional view) of a PDP. Hereinafter, the display principle of the PDP will be described with reference to FIG.
[0004]
Ultraviolet rays generated by discharging plasma between the two display electrodes 3 provided on the front glass substrate 1 excite the phosphors 6 separated by the barrier ribs 9 on the rear glass substrate 2 to generate visible light. Let The generated visible light passes through the MgO film 10, the surface dielectric layer 7, and the front glass substrate 1 and is displayed as an image. At this time, by applying a signal to the address electrode 5 provided on the rear glass substrate 2 and designating which discharge cell is to be displayed, the image can be made a required image.
[0005]
In order to generate and maintain the plasma, it is necessary to ensure insulation between the electrodes, and the surface dielectric layer 7 is provided to provide the insulation effect. The surface dielectric layer 7 is formed by applying a coating obtained by dispersing inorganic fine particles mainly composed of glass powder containing an element such as Si in an organic solvent together with a resin, drying, and then firing. It is obtained by. In the drying stage, the organic solvent as the solvent is vaporized, and in the baking stage, the resin is vaporized and the glass powder is dissolved and bonded to each other. And the surface dielectric layer 7 is formed by cooling after baking and becoming a glass film.
[0006]
The rear glass substrate 2 also has a rear dielectric layer 8 as a protective film for the address electrodes 5, and is produced in the same manner as the surface dielectric layer 7.
[0007]
A glass insulating film is usually used for the surface dielectric layer 7 and the back dielectric layer 8. For example, in Japanese Patent Application Laid-Open No. 2000-16835, a thin film as a protective film formed on the front glass substrate and the back glass substrate surface. As a paint for forming the insulating film and the thick insulating film covering the electrodes on both glass substrates, the average particle diameter is 0.3 to 1.5 μm and the maximum particle diameter is 10 μm or less. The use of an insulating paste containing 70 to 95% by weight of glass powder and 5 to 30% by weight of organic components has been proposed.
[0008]
The phosphor 6 is composed of three colors of R (red), G (green), and B (blue), and a partition wall 9 is provided to prevent the colors from being mixed. The partition wall 9 is a paint obtained by dispersing inorganic fine particles made of glass powder mainly containing an element such as Si in an organic solvent together with a resin, like the surface dielectric layer 7 and the back dielectric layer 8. Is applied and dried, and is exposed and developed into a desired pattern (photolithography method), or a desired pattern is scraped off by colliding fine particles such as Zr (sand blasting method).
[0009]
On the other hand, there are two known types of electron-emitting devices, a hot-cathode electron-emitting device and a cold-cathode electron-emitting device. In recent years, cold-cathode electrons that do not require standby power and are capable of high current density are known. An image forming apparatus using a light emitting element has attracted attention. As the cold cathode electron-emitting device, there are a field emission type (FE type), a metal / insulating layer / metal (MIM type), and the like. An image forming apparatus using a cold cathode electron-emitting device displays an image by irradiating a phosphor with an electron beam emitted from the electron-emitting device to generate fluorescence.
[0010]
In an image forming apparatus using such a cold cathode electron-emitting device, an insulating film made of a glass compound is used as in the plasma display panel. For example, the back glass substrate is provided with a plurality of electron-emitting devices and matrix wiring for connecting these devices. These wirings are installed in the X direction and the Y direction and intersect at the electrode portion of the electron-emitting device, but a strip-like insulating film is required to insulate both at the intersecting portion. Such an interlayer insulating film is formed with a film thickness of 10 to 100 μm, preferably 20 to 50 μm, using, for example, a glass compound containing lead oxide as a main component.
[0011]
For example, in Japanese Patent Application Laid-Open No. 9-283060, a lower wiring is formed under an insulating film, and then a strip-shaped insulating film is installed in a shape orthogonal to the lower wiring, and an upper wiring is formed on the insulating film.
[0012]
Therefore, an image forming apparatus using electron-emitting devices also requires an insulating film as in the case of the plasma display panel. The insulating film exhibits functions such as electrical insulation and a protective effect. It is necessary to have. These are usually formed by vacuum deposition, sputtering, coating, or the like.
[0013]
However, construction methods that require a vacuum, such as vacuum deposition and sputtering, are problematic in that they require expensive production equipment, especially in the case of FPDs that aim to increase the area as described above. The burden of manufacturing cost increases. Therefore, as an insulating film forming method in the FPD, an inexpensive coating method such as a screen printing method or a die coating method is frequently used.
[0014]
[Problems to be solved by the invention]
However, in the coating method, if the characteristics of the insulating film forming paint are not optimized, defects such as voids and pinholes are generated, and it is difficult to obtain a film having a desired insulating effect. The generation of voids and pinholes is considered to be caused by contamination of foreign matter or bubbles, and also by the wettability of the solvent constituting the coating material for forming an insulating film on the coated surface.
[0015]
When the wettability of the solvent to the coated surface is poor, repelling and accompanying voids occur, the insulating film becomes non-uniform, and the desired insulating effect cannot be obtained. Moreover, when unevenness exists on the surface to be coated, the probability of occurrence of repelling or voids increases. Further, when the coated surface is formed of two or more kinds of materials such as Ag provided in a stripe shape on the glass, repellency and voids are generated more remarkably. As a result, the insulating film becomes more non-uniform, and a portion where the insulating film is thinner than other portions is generated, so that a desired insulating effect cannot be obtained.
[0016]
Α-Terpineol or butyl carbitol acetate is generally used as a solvent for forming a coating material for forming an insulating film in the past, but these do not have good wettability with glass. It was the cause of voids, pinholes and peeling.
[0017]
Therefore, in order to obtain a desired insulation effect, many of the conventional coating materials for insulating film formation control the firing characteristics by paying attention to the composition of inorganic components, particularly glass powder, and are necessary for constituting the coating material. However, there is no one that controls the wettability with the coated surface by paying attention to the composition of the solvent as the dispersion medium.
[0018]
Accordingly, an object of the present invention is to provide a coating material for forming an insulating film that has good wettability with a surface to be coated and does not generate voids or pinholes after firing in order to solve the above-described problems of the prior art. The present invention also provides a plasma display panel in which a dielectric layer of a front glass substrate and a rear glass substrate, and a partition wall of the rear glass substrate are formed using the insulating film forming paint of the present invention, and a method for manufacturing the same. The purpose is to provide.
[0019]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have made the best mode of action of a coating for forming an insulating film on a glass substrate, an ITO (indium tin oxide) film, an Ag electrode, etc. Research was conducted on how to improve the above. As a result, by using a solvent having good wettability with respect to inorganic materials such as glass substrates, ITO films, Ag electrodes, etc. as a solvent constituting the paint, repellency between the paint and the coated surface, voids in the coating film, pins Since it is difficult for holes to occur and peeling due to poor adhesion between the paint and the coated surface does not occur, plasma display panels with a high withstand voltage can be produced at high yields by using them for the formation of dielectric layers on the surface glass substrate of plasma display panels. And the present invention has been completed.
[0020]
  Therefore, the present inventionA method for producing a substrate for a plasma display panel contains inorganic fine particles, a binder resin, and a solvent having a contact angle of less than 5 ° with respect to a glass substrate and an electrode formed on one surface side of the glass substrate. A paint is applied to one surface side of the glass substrate, and the glass substrate to which the paint is applied is heat treated.It is characterized by doing.
[0021]
  In the method for producing a substrate for a plasma display panel, the solvent is selected from diethyl carbitol, dipropylene glycol-n-propyl ether, tripropylene glycol monomethyl ether, diethyl cellosolve, carbitol acetate, dibutyl cellosolve and propylene glycol diacetate. It is preferable to contain 50% by mass or more of at least one selected solvent. By using this solvent, the wettability of the paint with respect to the glass substrate is improved.
[0022]
  Also,In the manufacturing method of the said substrate for plasma display panels, it is preferable to contain the said inorganic fine particle in the ratio of 10-95 mass%, the said binder resin 1-20 mass%, and the said solvent 4 to 85 mass%.
[0023]
  Also,In the manufacturing method of the said substrate for plasma display panels, it is preferable that the average particle diameter of the said inorganic fine particle is 0.1-10 micrometers.
[0024]
  further,In the method for manufacturing a substrate for a plasma display panel, it is preferable that the glass substrate is subjected to an ultraviolet cleaning process. Thereby, since the organic stain | pollution | contamination on a glass substrate or an electrode can be removed, the applicability | paintability of the coating material to a glass substrate or an electrode can be improved, and a repellency can be suppressed.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
[0039]
  The present inventionUsed inInsulating film forming paint(Hereinafter, it is also referred to as the insulating film-forming paint of the present invention.)Is suitably used for forming an insulating film in an image forming apparatus using a plasma display panel, a plasma addressed liquid crystal display, or an electron-emitting device.
[0040]
The coating material for forming an insulating film of the present invention comprises an inorganic fine particle (a), a binder resin (b) of the inorganic fine particle, and a solvent (c) for dissolving the binder resin as essential components. A coating material for forming an insulating film for forming a film, wherein a solvent having a contact angle with respect to the inorganic material of less than 5 ° is used. That is, the coating material for forming an insulating film of the present invention includes an organic component comprising at least an inorganic component composed of inorganic fine particles (a), a resin (b) as a binder for the inorganic component, and a solvent (c) for dissolving the resin. The contact angle of the solvent to the inorganic material is less than 5 °. The solvent is used to disperse the inorganic components and dissolve the binder resin.
[0041]
The coating material for forming an insulating film according to the present invention is applied to a desired portion of an inorganic material to be a coated surface at a desired thickness, processed or patterned as necessary, and then baked to thermally decompose organic components. The insulating film is released (debindered). If the wettability of the insulating film-forming paint to the coated surface is poor, repelling occurs between the painted and the coated surface, voids or pinholes occur in the coating film, and adhesion between the painted and the coated surface The film peels off due to defects. Therefore, in order to prevent the occurrence of voids and pinholes and peeling, it is important that the wettability of the coating surface to the coated surface is good. In addition, the wettability of the paint to the coated surface is mainly affected by the wettability of the solvent that constitutes the paint to the coated surface, so it is necessary that the solvent has good wettability to the coated surface material. From this viewpoint, the contact angle of the solvent with respect to the inorganic material is preferably less than 5 °.
[0042]
Here, the contact angle can be measured by a known method using a contact angle measuring device or the like.
[0043]
In addition, the coating material for forming an insulating film of the present invention is preferably used for forming a partition wall on a back plate of a plasma display panel. This partition is usually formed on a back dielectric layer as an address electrode protective film, and the back dielectric layer is made of a glass thin film or a ceramic thin film. Therefore, the coating material for forming an insulating film needs to have good wettability with respect to the glass compound and the ceramic compound, and in particular, the contact angle of the solvent with respect to the glass compound and the ceramic compound is preferably less than 5 °.
[0044]
The method of patterning the partition walls using the insulating film forming paint is not particularly limited, but for example, the patterning is repeated by screen printing, or the entire surface is applied by screen printing or die coating, and then the pattern is cut by sandblasting. There is a way to start. When the contact angle of the solvent with respect to the glass compound or ceramic compound is 5 ° or more, the wettability of the paint to the back surface dielectric layer, which is the coated surface, becomes poor, and the partition wall may collapse due to voids generated in the partition wall. This is not preferable because the method of sandblasting becomes uneven.
[0045]
The coating material for forming an insulating film according to the present invention includes a dielectric layer and a protective film in a plasma display panel and a plasma addressed liquid crystal display, an element electrode in an image forming apparatus using an electron-emitting device, and an interlayer insulating film for upper and lower wirings. It is preferably used for formation. Both are performed on a glass substrate such as lead glass and blue plate glass, a metal electrode such as silver (Ag) formed on the glass substrate, and a ceramic electrode such as ITO (indium tin oxide). In addition, there are cases where black stripes or the like are present on the glass substrate for improving contrast, but the black stripes are mainly a mixture (compound) of a ceramic black pigment such as ruthenium oxide and powdered glass. Therefore, the insulating film-forming coating material needs to have good wettability with respect to any of the glass compound, the metal compound, and the ceramic compound, and in particular, with respect to any of the glass compound, the metal compound, and the ceramic compound, The contact angle of the solvent is preferably less than 5 °. If the contact angle of the solvent with respect to the glass compound, metal compound and ceramic compound is 5 ° or more, the wettability of the paint to the glass substrate or electrode is reduced, so voids and voids are generated in the coating film due to air bubbles mixed in during coating. Therefore, it is not preferable.
[0046]
The solvent (c) used in the coating material for forming an insulating film of the present invention is not particularly limited as long as the contact angle with respect to the inorganic material is less than 5 °. For example, diethyl carbitol, dipropylene glycol-n-propyl ether, Examples include tripropylene glycol monomethyl ether, diethyl cellosolve, carbitol acetate, dibutyl cellosolve, and propylene glycol diacetate. These solvents may be used alone or in any combination.
[0047]
In general, when the solvent is composed of two or more organic solvents, the wettability is greatly influenced by the abundance ratio of each solvent. For example, when a solvent having good wettability to a glass substrate and a solvent having poor wettability are mixed, the higher the ratio of the solvent having good wettability, the better the wettability of the mixed solvent to the glass substrate. Here, the seven organic solvents described above all have a contact angle of less than 5 ° with respect to any of the glass compound, ceramic compound and metal compound, and have very good wettability with respect to the inorganic material. Therefore, good wettability is exhibited not only on a glass substrate but also on a composite substrate in which a metal electrode or the like is formed on the glass substrate. Therefore, as a solvent in the insulating film forming paint, containing at least 50% by mass of at least one selected from the above seven solvents improves the wettability of the insulating film forming paint to the coated surface, It is more preferable in terms of preventing generation of voids and pinholes.
[0048]
Further, as the solvent (c), in addition to the seven organic solvents described above, a mixed solvent obtained by mixing other solvents may be used as long as the effects of the present invention are not impaired. Examples of the solvent that can be mixed include terpenes such as α-, β-, and γ-terpineol, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, diethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, ethylene glycol monoalkyl. Ether acetates, ethylene glycol dialkyl ether acetates, diethylene glycol monoalkyl ether acetates, diethylene glycol dialkyl ether acetates, propylene glycol monoalkyl ethers, propylene glycol dialkyl ethers, propylene glycol monoalkyl ether acetates, propylene glycol dialkyl ether acetate Dipropylene glycol Monoalkyl ethers, dipropylene glycol dialkyl ethers, dipropylene glycol monoalkyl ether acetates, dipropylene glycol dialkyl ether acetates, tripropylene glycol monoalkyl ethers, tripropylene glycol dialkyl ethers, tripropylene glycol trialkyl ether And tripropylene glycol monoalkyl ether acetates, tripropylene glycol dialkyl ether acetates, tripropylene glycol trialkyl ether acetates, alcohols such as methanol, ethanol, isopropanol, and 1-butanol. These solvents may be used alone or as a mixture of any two or more kinds.
[0049]
Among these, as the solvent (c), it is preferable to use at least two solvents selected from diethyl carbitol, dipropylene glycol-n-propyl ether, tripropylene glycol monomethyl ether and diethyl cellosolve. This is because these four kinds of organic solvents have good wettability with respect to all of glass compounds, ceramic compounds, and metal compounds regardless of whether or not they are washed with ultraviolet rays, and can be manufactured at low cost. The four organic solvents have boiling points of 10 ° C. or more (minimum is 121 ° C. for diethyl cellosolve, 242 ° C. for tripropylene glycol monomethyl ether), and all have different drying rates. For this reason, by combining two or more kinds, it is possible to prevent a phenomenon in which the solvent component suddenly volatilizes from the inside of the coating film during drying. As a result, the generation of voids and pinholes in the dry film and the roughening of the dry film surface are also suppressed.
[0050]
When preparing the coating material for forming an insulating film of the present invention, the ratio of the solvent (c) is 4 to 85% by mass, preferably 5 to 60% by mass, and more preferably 10 to 10% by mass with respect to the entire coating material for forming an insulating film. It is good to set it as 40 mass%. When the content of the solvent is less than 4% by mass, the fluidity of the coating is lowered and the coating property is deteriorated. On the other hand, when the content exceeds 85% by mass, the shrinkage during drying is large and causes defects. In addition, it is a cause of high costs.
[0051]
The inorganic fine particles (a) that are inorganic components contained in the coating material for forming an insulating film of the present invention are not particularly limited, and all fine particles made of a known inorganic compound capable of forming an insulating film can be used. Of these, metal oxides are preferably used. In particular, SiO₂, ZnO, B₂O_Three, PbO, Bi₂O_Three, BaO, P₂O_FiveMetal oxides such as CaO, SrO and MgO are preferred. In low-melting glass generally used as an insulating film, glass powder in which two or more of these oxides are mixed is used. In particular, glass powder containing PbO as a main component is preferably used because it is easy to control in terms of softening point adjustment and the like. Therefore, by mixing the fine particles with the coating material for forming an insulating film, the insulating properties of the coating material are improved. These inorganic fine particles may be used alone or in any combination.
[0052]
The inorganic fine particles (a) may have an average particle size in the range of 0.1 to 10 μm, preferably in the range of 0.3 to 7 μm, and more preferably in the range of 0.5 to 5 μm. When this average particle size is less than 0.1 μm, the fine particles are highly agglomerated and defects tend to occur in the coating film. On the other hand, when it exceeds 10 μm, the filling rate inside the coating film decreases and defects occur. It is because it becomes easy.
[0053]
When preparing the insulating film-forming paint of the present invention, the proportion of the inorganic fine particles (a) is 10 to 95% by weight, preferably 40 to 90% by weight, more preferably, based on the whole insulating film-forming paint. It is good to set it as 60-80 mass%. If this content is less than 10% by mass, the loss during drying / firing is large and the cost is high. On the other hand, if it exceeds 95% by mass, the fluidity of the paint is lowered and the applicability is deteriorated. is there.
[0054]
The binder resin (b) contained in the coating material for forming an insulating film of the present invention is not particularly limited, and any conventionally known one can be used as long as it can function as a binder for the inorganic fine particles. By using these binder resins, the inorganic fine particles are homogeneously dispersed in the organic solvent, and it is possible to prevent the coating film from being deformed after the coating is applied and dried.
[0055]
Preferred examples include cellulose resins such as nitrocellulose, ethyl cellulose, and hydroxyethyl cellulose, acrylic resins such as polybutyl acrylate and polymethacrylate, copolymers thereof, polyvinyl alcohol, and polyvinyl butyral. The binder resin may be used alone or in combination of two or more in the insulating film forming paint.
[0056]
When preparing the insulating film-forming paint of the present invention, the ratio of the binder resin (b) is 0.1 to 20% by mass, preferably 0.5 to 10% by mass, based on the entire insulating film-forming paint. More preferably, the content is 1 to 5% by mass. When this content is less than 0.1% by mass, the amount necessary for maintaining the shape of the coating film (dried film) is insufficient, resulting in loss of shape. On the other hand, when it exceeds 20 mass%, the loss at the time of baking is large and it becomes easy to produce a defect.
[0057]
Furthermore, at least one compound selected from ceramics such as titania, alumina, barium titanate, zirconia, and refractory glass may be added as filler (d) to the coating material for forming an insulating film of the present invention. it can. These fillers have effects such as reducing the thermal expansion coefficient, reducing the shrinkage rate during firing, and reducing the stress applied to the substrate. In particular, when a white filler is used, since the reflection of display light is improved, a plasma display panel that provides an image with high luminance can be obtained. The amount of filler added is not particularly limited as long as it does not impair the function of the insulating film-forming coating material, but is usually 1 to 20% by mass, preferably 2 to 10% by mass with respect to the entire coating material. Is preferable from the viewpoint of controlling the thermal expansion coefficient.
[0058]
The glass compound used as the inorganic fine particles is generally in a powder state because it is synthesized by rapidly cooling and pulverizing the molten glass compound. Therefore, in order to uniformly disperse the powder glass, the organic solvent for dispersing the powder glass, the powder glass in the organic solvent, and to prevent the coating film after coating and drying from being out of shape. By containing at least a resin as a binder, a paint can be produced.
[0059]
The coating material thus prepared is applied and dried, and then baked to obtain a desired insulating film. Since the organic solvent as a dispersion medium volatilizes during drying and the resin as a binder volatilizes during firing, the glass component remains at the end. Note that the organic solvent as the dispersion medium and the resin as the binder are necessary so that an inexpensive coating-type forming method can be used when the glass powder is formed as an insulating film.
[0060]
From the above, as the inorganic component such as the inorganic fine particles (a) and filler (d) used in the coating material for forming an insulating film of the present invention, a compound that forms glass by firing is preferable.
[0061]
Furthermore, the coating composition for forming an insulating film of the present invention includes a dispersant, a plasticizer, a viscosity modifier, an oligomer, a polymer, an ultraviolet light absorber, a photosensitive monomer, a photopolymerization initiator, a sensitizer and the like as necessary. Can be added. Examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol, and glycerin. Examples of the viscosity modifier include thixotropic agents such as Aerosil. The blending ratio of these additives is not particularly limited as long as it does not impair the function of the insulating film-forming paint, but is usually 0.01 to 20% by mass, preferably 0.1% with respect to the whole paint. It is preferable from the point of the defect generation | occurrence | production suppression at the time of baking to be -5 mass%.
[0062]
When preparing the coating for forming an insulating film of the present invention, for example, inorganic fine particles, binder resin, solvent, dispersant, plasticizer, oligomer, polymer, ultraviolet light absorber, photosensitive monomer, photopolymerization initiator, sensitizer In addition, various components such as other additives and a solvent are blended so as to have a desired composition, and then mixed and dispersed homogeneously by a dispersing machine such as a three-roller, a ball mill, or a sand mill.
[0063]
The coating material for forming an insulating film of the present invention can be suitably used for forming an insulating film of an image forming apparatus using a plasma display panel, a plasma addressed liquid crystal display, or an electron-emitting device.
[0064]
Next, the manufacturing method of the plasma display panel back plate of the present invention using the insulating film forming paint of the present invention will be described with reference to FIG.
[0065]
In the back plate of a plasma display panel, an address electrode 5, a back dielectric layer 8 as a protective film, a partition wall 9 and a phosphor 6 are usually formed on a back glass substrate 2. Therefore, when manufacturing the back plate, first, the address electrodes 5 are formed on the back glass substrate 2. The electrode material is preferably a metal compound such as Ag or Cr—Cu—Cr from the viewpoint of resistance value, adhesion to a glass substrate, and the like. Moreover, it can be set as the address electrode excellent in adhesiveness with a board | substrate by containing a small amount of glass components in an electrode material.
[0066]
First, the back dielectric layer 8 as the address electrode protective film is formed on the back glass substrate 2 on which the address electrodes 5 are formed, using the insulating film forming paint of the present invention. Specifically, the coating film for forming an insulating film of the present invention is applied to form a dielectric coating film so that the thickness after firing becomes 2 to 10 μm to form a dielectric coating film, and then fired to obtain an address electrode. The back dielectric layer 8 which is a protective film can be manufactured.
[0067]
As a method for applying the insulating film-forming paint, a general method such as a screen printing method, a bar coater method, a roll coater method, a die coater method, or a doctor blade method can be used. The firing atmosphere and temperature vary depending on the characteristics of the paint and the substrate, but it is preferable to fire in an atmosphere of air, nitrogen, or the like. As the firing furnace, a batch-type firing furnace, a belt-type or walking beam-type continuous firing furnace can be used. Although a calcination temperature is not specifically limited, Usually, it calcinates at 400-600 degreeC.
[0068]
Furthermore, as described above, when a dielectric coating film is formed by applying an insulating film-forming coating material, it is preferable that a cleaning step using ultraviolet rays be included in the pre-process of the coating process. UV cleaning is the energy of UV and the oxygen produced by it._ThreeTo decompose and oxidize organic compounds and finally CO₂And H₂This is a method of gasifying and removing dirt by reacting to O. By cleaning with ultraviolet rays, organic stains on the glass substrate and electrode can be removed, and the wettability of the paint to the glass substrate and electrode can be made uniform on the substrate, and the wettability in the substrate surface is not uniform. It is possible to suppress repelling due to.
[0069]
The back dielectric layer 8 can also be manufactured by making the organic component of the coating material for forming the insulating film photosensitive, forming a dielectric coating film by a method such as full exposure, and firing.
[0070]
Next, a partition wall 9 is formed on the plasma display panel back plate on which the back dielectric layer 8 is formed, using the insulating film forming paint of the present invention. Specifically, the dielectric coating film is formed by applying the coating for forming an insulating film of the present invention to 300 to 600 μm so that the thickness after firing becomes 100 to 200 μm. A partition wall 9 can be manufactured by applying a patterned protective film on the dielectric coating film, scraping a portion that is not protected by the sandblast method, removing the protective film, and baking.
[0071]
As a coating method and a firing method, the same general method as that for the back dielectric layer 8 can be used.
[0072]
Further, as in the case of the back dielectric layer 8, it is preferable that a cleaning process using ultraviolet rays is provided in the pre-process of the coating process. By UV cleaning, the wettability of the paint to the back surface dielectric layer 8 can be made uniform on the substrate, and repelling due to non-uniform wettability within the substrate surface can be suppressed.
[0073]
The partition wall 9 can also be manufactured by making the organic component of the coating material for forming the insulating film photosensitive, forming a dielectric coating film by a photolithography method such as pattern exposure, and baking. The photolithography method is preferable in that a high-definition partition wall 9 with a high aspect ratio can be obtained.
[0074]
Further, as described above, the back dielectric layer 8 and the barrier ribs 9 are not fired individually, but can be fired at the same time to manufacture the back plate of the plasma display panel.
[0075]
As described above, according to the method for manufacturing the plasma display panel back plate of the present invention, the back dielectric layer 8 and the barrier ribs 9 can be manufactured with a high yield.
[0076]
Moreover, the plasma display panel back plate manufactured by the method for manufacturing a plasma display panel back plate of the present invention can be preferably used because it has few voids and pinholes and has an excellent insulating effect.
[0077]
Then, the manufacturing method of the plasma display panel surface board of this invention using the coating material for insulating film formation of this invention is demonstrated using FIG.
[0078]
As described above, the front plate of the plasma display panel is provided with the transparent electrode 4 on the front glass substrate 1, the two display electrodes 3 on the front glass substrate 1, and the surface dielectric layer 7, In general, an MgO film 10 as a protective film is formed.
[0079]
Since the surface dielectric layer 7 is provided to prevent a short circuit (leakage) between the display electrodes 3 and between the display electrodes 3 and the address electrodes 5, it is necessary to have a desired insulating effect. . However, it is not necessary to form a pattern like the partition wall 9 provided on the rear glass substrate 2, and on the contrary, a flat and highly transparent thin film is required to suppress display unevenness. Therefore, it can be manufactured by applying a coating for forming an insulating film by a printing method, drying and baking.
[0080]
First, the transparent electrode 4 generally made of ITO is formed on the surface glass substrate 1 by sputtering or the like. Subsequently, patterning is performed by screen printing or photolithography, and baking is performed to form the display electrode 3. As the electrode material, the same material as that of the address electrode 5 can be used. Here, the transparent electrode 4 is not necessarily required, and the display electrode 3 can also be directly formed on the surface glass substrate 1.
[0081]
Next, the dielectric film-forming paint of the present invention is applied to form a dielectric coating film by coating 30 to 150 μm so that the thickness after firing becomes 10 to 50 μm, and then the surface dielectric layer 7 is formed by firing. Form. As a coating method and a firing method, the same general methods as those for the back dielectric layer 8 and the partition walls 9 can be used.
[0082]
Further, as in the case of the back dielectric layer 8 and the partition wall 9, it is preferable to have a cleaning step using ultraviolet rays in the pre-process of the coating process. By washing with ultraviolet rays, the wettability of the paint to the surface glass substrate 1 and the transparent electrode 4 can be made uniform on the substrate, and repellency due to nonuniform wettability within the substrate surface can be suppressed.
[0083]
The surface dielectric layer 7 can also be manufactured by making the organic component of the insulating film-forming coating material photosensitive, forming a dielectric coating film by a photolithography method such as pattern exposure, and baking.
[0084]
Therefore, the plasma display panel surface plate manufactured by the method for manufacturing a plasma display panel surface plate of the present invention can be preferably used because it has few voids and pinholes and has an excellent insulating effect.
[0085]
Subsequently, the present invention will be specifically described below using examples. However, the present invention is not limited to this. In addition, the density | concentration of% display in an Example is the mass%, when there is no notice.
[0086]
【Example】
(Examples 1 to 6 and Comparative Examples 1 and 2)
About the organic solvent shown below, the wettability with respect to each inorganic material board | substrate of an organic solvent was evaluated by measuring a contact angle. As the inorganic material substrate, a glass substrate (PD-200: manufactured by Asahi Glass Co., Ltd.) and a glass substrate on which ITO, Ag, Cu, and Cr were deposited on the entire surface were used. In addition, the contact angle of the substrate washed with ultraviolet rays (hereinafter referred to as “UV”) after electrode formation was also measured.
Example 1: Diethyl carbitol (diethylene glycol diethyl ether)
Example 2: Dipropylene glycol-n-propyl ether
Example 3: Tripropylene glycol monomethyl ether
Example 4: Diethyl cellosolve (ethylene glycol diethyl ether)
Example 5: Carbitol acetate (diethylene glycol monoethyl ether acetate)
Example 6: Dibutyl cellosolve (ethylene glycol dibutyl ether)
Example 7: Propylene glycol diacetate
Comparative Example 1: α-terpineol
Comparative Example 2: Butyl carbitol acetate (diethylene glycol mono-n-butyl ether acetate)
[0087]
(Measurement method of contact angle)
The contact angle was measured using a CA-X contact angle meter manufactured by Kyowa Interface Science Co., Ltd. In each sample, the lengths from the tip of the injection needle to the lower end of the droplet were made constant, and the amount of the droplet was made uniform. After a certain amount of droplets were dropped on the substrate to form droplets on the substrate, the contact angle after 5 seconds of dropping was measured on an enlarged monitor. As shown in FIG. 2, the contact angle is measured by measuring the height (h) to the top of the droplet and the length (2r) of the interface between the droplet and the substrate, and using the following formula by the Height / Width method. This is the value obtained.
TanΘ₁= H / r, contact angle Θ = 2Θ₁
[0088]
The measurement results are shown in Table 1. In addition, the contact angle measurement result showed the average value of the result measured 5 times. However, when the variation is large, the range is shown.
[0089]
[Table 1]

[0090]
From Table 1, as shown in Comparative Examples 1 and 2, in the solvent constituting the current insulating film forming paint, a metal compound such as Ag, Cu, Cr has good wettability, but a ceramic compound such as ITO. Then, α-terpineol was slightly poor in wettability, and wettability was worse on the glass substrate. This was the same result for the substrate subjected to UV cleaning.
[0091]
On the other hand, the solvent of Examples 1-4 was excellent in wettability with respect to any of a glass substrate, a metal compound, and a ceramic compound, and was the same after UV cleaning.
[0092]
The solvent of Example 5 resulted in a slight change in contact angle depending on the measurement location on the substrate, but showed good wettability at any location on the substrate after UV cleaning.
[0093]
The solvent of Examples 6 and 7 was found to have poor wettability with respect to the glass substrate, metal compound, and ceramic compound on the untreated substrate, but the substrate was wetted by applying UV cleaning to the substrate. The characteristics were greatly improved and no variation was observed.
[0094]
(Preparation of paint for insulating film formation)
Moreover, the coating material for insulating film formation was produced with the following composition ratios and methods using the solvent which makes the organic solvent used by said contact angle measurement 100%. 200 g of a vehicle (solvent in which resin is dissolved) containing 10% ethyl cellulose (made by Dow Chemical, trade name “Etocel STD-7”, polymerization degree 60,000), and lead oxide glass having an average particle diameter of 3 μm as glass powder Frit (Composition system: PbO-MgO-B₂O_Three-SiO₂) 300 g was mixed and pre-kneaded and kneaded with three rolls to obtain an insulating film-forming coating material.
[0095]
(Evaluation of withstand voltage)
The insulation property (voltage resistance) of the dielectric layer obtained by applying this insulating film forming paint was measured by the following method.
[0096]
A fired Ag paste was printed on a glass substrate (PD-200) and fired at 590 ° C. to form a lower electrode. On this, the coating material for forming an insulating film of the present invention was printed in such a manner that the end portion of the lower electrode was exposed and baked at 590 ° C. The printing conditions were adjusted so that the thickness of the dielectric layer after firing was 30 μm. Further, a thermosetting type Ag paste was applied on this so as to fit in the area of the lower electrode, and heated at 150 ° C. to form the upper electrode. A contact point was formed opposite to the end portions of the upper electrode and the lower electrode, and a withstand voltage value was measured with a breakdown voltage measuring device (manufactured by Kikusui Electronics Co., Ltd.) assuming that 0.5 mA of power leaked as a dielectric breakdown. Similarly, the withstand voltage of the dielectric layer formed on the Cr—Cu—Cr electrode was also measured.
[0097]
In addition, as the base electrode of the Ag electrode (lower electrode), the Ag electrode (lower electrode) was formed by the above-described method on a glass substrate (PD-200) in which an ITO electrode was formed with a thickness of 2 μm by patterning by sputtering. Things were also prepared. In the same manner as described above, the dielectric strength was measured in the same manner on the substrate on which the dielectric layer was formed using the coating material for forming an insulating film of the present invention and the upper electrode was formed with a thermosetting type Ag paste. Similarly, the withstand voltage of the dielectric layer formed on the Cr—Cu—Cr electrode was also measured.
[0098]
The above measurement results are summarized in Table 1.
[0099]
As is clear from Table 1, the dielectric layers produced from the insulating film-forming paints of Examples 1 to 4 were free from voids and pinholes and had good withstand voltage characteristics.
[0100]
The dielectric layer produced from the insulating film forming paint of Example 5 has no withstand voids or pinholes, and has withstand voltage characteristics sufficient for practical use even when the substrate is not yet processed. However, the dielectric layer has further improved withstand voltage characteristics by performing UV cleaning.
[0101]
The dielectric layers prepared from the insulating film-forming paints of Examples 6 and 7 had insufficient withstand voltage characteristics when produced on an untreated substrate, but they were put to practical use by performing UV cleaning. Therefore, the dielectric layer had sufficient withstand voltage characteristics.
[0102]
On the other hand, the dielectric layers produced from the insulating film forming paints of Comparative Examples 1 and 2 both had voids and pinholes, and the withstand voltage characteristics were slightly inferior to the withstand voltage characteristics of the examples. there were.
[0103]
(Evaluation of address electrode protection effect)
Next, the effect as an address electrode protective film was evaluated. A fired Ag paste was printed on a glass substrate (PD-200) and fired at 590 ° C. to form a lower electrode. On this, the coating material for forming an insulating film of the present invention was printed so as to cover the entire surface so as to have a film thickness of 3 μm after baking, and was baked at 590 ° C. The obtained insulating film is formed by one application. The results are shown in Table 1.
[0104]
The address electrode protection effect was evaluated according to the following criteria.
○: No voids or pinholes
×: Void or pinhole occurs
[0105]
As is clear from Table 1, the address electrode protective films produced from the insulating film forming paints of Examples 1 to 5 were free from defects such as voids and pinholes and exhibited sufficient effects as protective films.
[0106]
The address electrode protective film produced from the insulating film-forming paints of Examples 6 and 7 had insufficient voids and pinholes in the untreated substrate, and was insufficient as the protective film. There were no defects such as pinholes, and it showed a sufficient effect as a protective film.
[0107]
On the other hand, the address electrode protective film produced from the insulating film forming paints of Comparative Examples 1 and 2 was insufficient as a protective film because voids and pinholes were generated.
[0108]
(Evaluation as a partition)
On the glass substrate (PD-200), the insulating film-forming coating material of the present invention is applied and dried so as to have a film thickness after baking of 200 μm, covered with a patterned protective film, and then separated by a sandblast method. A pattern was formed. And after removing a protective film, it baked at 590 degreeC and the partition was formed. The evaluation results are shown in Table 1.
[0109]
The partition walls were evaluated according to the following criteria.
○: No voids or pinholes, no separation of partition walls
Δ: No voids or pinholes are generated, but the partition walls are peeled off
×: Voids and pinholes are generated, and the partition walls are peeled off
[0110]
As is apparent from Table 1, the partition walls made from the insulating film forming paints of Examples 1 to 4 are free from defects such as voids and pinholes, and part of the partition walls does not peel off from the glass substrate. It was.
[0111]
The partition wall produced from the insulating film forming paint of Example 5 did not generate voids or pinholes, but sometimes the partition wall peeled off. However, the occurrence of separation of the partition walls was suppressed by performing UV cleaning.
[0112]
The partition walls produced from the insulating film-forming paints of Examples 6 and 7 sometimes had voids and pinholes on the untreated substrate, and the partition walls were peeled off. Occurrence and peeling of the partition wall did not occur, and it was sufficient as a partition wall.
[0113]
On the other hand, in the address electrode protective film produced from the insulating film forming paints of Comparative Examples 1 and 2, voids and pinholes were generated, and there were places where the partition walls were not formed, and some of the partition walls were peeled off.
[0114]
[Table 2]

[0115]
[Table 3]

[0116]
(Examples 8 to 11 and Comparative Examples 3 and 4)
About each mixed solvent produced by mixing the organic solvent in the ratio shown in Table 2, the wettability was evaluated in the same manner as in Examples 1 to 7 and Comparative Examples 1 and 2. However, DCr: diethyl carbitol, CrAc: carbitol acetate, BCA: butyl carbitol acetate. Similarly, a coating material for forming an insulating film was prepared, and the withstand voltage, the address electrode protection effect, and the effect as a partition were evaluated. These results are shown in Table 3.
[0117]
As is apparent from Table 3, the dielectric layers produced from the insulating film forming paints of Examples 8 and 9 were free from voids and pinholes and had good withstand voltage characteristics.
[0118]
The dielectric layers made from the insulating film forming paints of Examples 10 and 11 have no withstand voids or pinholes, and have withstand voltage characteristics sufficient for practical use even when the substrate is not processed. However, the dielectric layer has further improved withstand voltage characteristics by performing UV cleaning.
[0119]
The dielectric layers prepared from the insulating film-forming paints of Comparative Examples 3 and 4 both had voids and pinholes, and had a slightly poor withstand voltage characteristic.
[0120]
Further, as is apparent from Table 3, the address electrode protective film produced from the insulating film forming paints of Examples 8 to 11 has no defects such as voids and pinholes, and is a protective film. As a sufficient effect.
[0121]
On the other hand, the address electrode protective film produced from the insulating film-forming paints of Comparative Examples 3 and 4 was insufficient as a protective film because voids and pinholes were generated.
[0122]
Further, as apparent from Table 3, the partition walls produced from the insulating film forming paints of Examples 8 and 9 are free from defects such as voids and pinholes, and a part of the partition walls is made of glass. There was no peeling from the substrate. In the partition walls produced from the insulating film-forming paints of Examples 10 and 11, no voids or pinholes were generated, but the partition walls might be peeled off. However, the occurrence of separation of the partition walls was suppressed by performing UV cleaning.
[0123]
On the other hand, in the address electrode protective film prepared from the insulating film forming paints of Comparative Examples 3 and 4, voids and pinholes were generated, and there were places where the partition walls were not formed, or some of the partition walls were peeled off.
[0124]
[Table 4]

[0125]
(Examples 12 to 17)
The wettability was evaluated in the same manner as in Examples 1 to 11 and Comparative Examples 1 to 4 for each of the mixed solvents prepared by mixing organic solvents at the ratio shown in (Table 4). However, DECe: diethyl cellosolve, DCr: diethyl carbitol, DPnP: dipropylene glycol-n-propyl ether, TPM: tripropylene glycol monomethyl ether. Similarly, a coating material for forming an insulating film was prepared, and the withstand voltage, the address electrode protection effect, and the effect as a partition were evaluated. These results are shown in Table 5.
[0126]
[Table 5]

[0127]
As is clear from Table 5, the dielectric layers produced from the insulating film forming paints of Examples 12 to 17 were free from voids and pinholes and had good withstand voltage characteristics. In addition, the withstand voltage characteristics were improved as compared with Examples 1 to 7 in which the solvent was a single component and Examples 8 to 11 containing a solvent having poor wettability.
[0128]
Further, as apparent from Table 5, the address electrode protective film produced from the insulating film forming paints of Examples 12 to 17 has no defects such as voids and pinholes, and is a protective film. As a sufficient effect.
[0129]
Further, as is apparent from Table 5, the partition walls made from the insulating film forming paints of Examples 12 to 17 are free from defects such as voids and pinholes, and part of the partition walls may be peeled off from the glass substrate. It was sufficient as a partition wall.
[0130]
(Examples 18 to 24 and Comparative Examples 5 and 6)
When the glass substrate is blue plate glass (# 0050: manufactured by Matsunami Glass Industrial Co., Ltd.), the contact angle of the organic solvent shown below was tested in the same manner as in Examples 1 to 7 and Comparative Examples 1 and 2. Table 6 shows the contact angles of the respective solvents with respect to the blue plate glass.
Example 18: Diethyl carbitol (diethylene glycol diethyl ether)
Example 19: Dipropylene glycol-n-propyl ether
Example 20: Tripropylene glycol monomethyl ether
Example 21: Diethyl cellosolve (ethylene glycol diethyl ether)
Example 22: Carbitol acetate (diethylene glycol monoethyl ether acetate)
Example 23: Dibutyl cellosolve (ethylene glycol dibutyl ether)
Example 24: Propylene glycol diacetate
Comparative Example 5: α-Terpineol
Comparative Example 6: Butyl carbitol acetate (diethylene glycol mono-n-butyl ether acetate)
Moreover, the coating material for insulating film formation was similarly produced, and it carried out similarly to Examples 1-7 and Comparative Examples 1 and 2 except having used blue plate glass (# 0050) instead of the glass substrate (PD-200). The withstand voltage, the address electrode protection effect, and the effect as a partition were evaluated. These results are shown in Table 6.
[0131]
[Table 6]

[0132]
From Table 6, as in Comparative Examples 5 and 6, the solvent constituting the current coating material for forming an insulating film had poor wettability with respect to the glass substrate, and the same result was obtained with respect to the substrate subjected to UV cleaning.
[0133]
The solvents of Examples 18 to 21 were excellent in wettability with respect to the glass substrate, and were the same after UV cleaning.
[0134]
The solvent of Example 22 had a result that the contact angle varied slightly depending on the measurement location on the substrate, but showed good wettability at any location on the substrate after UV cleaning.
[0135]
The solvents of Examples 23 and 24 were found to have poor wettability with respect to the glass substrate on the untreated substrate. However, when the substrate was subjected to UV cleaning, the wettability to the substrate was greatly improved, and variation was observed. Was also not seen.
[0136]
Further, as is apparent from Table 6, the dielectric layers produced from the insulating film forming paints of Examples 18 to 21 had no voids or pinholes and had good withstand voltage characteristics.
[0137]
The dielectric layer produced from the insulating film-forming paint of Example 22 has no withstand voids or pinholes, and has withstand voltage characteristics sufficient for practical use even when the substrate is not yet processed. However, the dielectric layer has further improved withstand voltage characteristics by performing UV cleaning.
[0138]
The dielectric layers produced from the insulating film-forming paints of Examples 23 and 24 had insufficient withstand voltage characteristics when produced on an untreated substrate, but they were put to practical use by performing UV cleaning. Therefore, the dielectric layer had sufficient withstand voltage characteristics.
[0139]
On the other hand, the dielectric layers produced from the insulating film-forming paints of Comparative Examples 5 and 6 both had voids and pinholes, and were somewhat inferior in withstand voltage characteristics.
[0140]
Further, as is apparent from Table 6, the address electrode protective film produced from the insulating film forming paints of Examples 18 to 22 has no defects such as voids and pinholes, and exhibits a sufficient effect as a protective film. It was.
[0141]
The address electrode protective film produced from the insulating film forming paints of Examples 23 and 24 was insufficient as a protective film because voids and pinholes were generated on the untreated substrate, but voids and pinholes were not obtained on the UV cleaned substrate. There were no defects such as pinholes, and it showed a sufficient effect as a protective film.
[0142]
On the other hand, the address electrode protective film produced from the insulating film forming paint of Comparative Examples 5 and 6 was insufficient as a protective film because voids and pinholes were generated.
[0143]
Further, as apparent from Table 6, the partition walls produced from the coating materials for forming the edge films of Examples 18 to 21 are free from defects such as voids and pinholes, and part of the partition walls may be peeled off from the glass substrate. There was no.
[0144]
The partition wall produced from the coating material for forming an insulating film of Example 22 did not generate voids or pinholes, but sometimes the partition wall peeled off. However, the occurrence of separation of the partition walls was suppressed by performing UV cleaning.
[0145]
The partition walls produced from the insulating film forming paints of Examples 23 and 24 sometimes had voids and pinholes on the untreated substrate, and the separation of the partition walls. Occurrence and peeling of the partition wall did not occur, and it was sufficient as a partition wall.
[0146]
On the other hand, in the address electrode protective film prepared from the insulating film forming paints of Comparative Examples 5 and 6, voids and pinholes were generated, and a part where the partition wall was not formed was generated, or a part of the partition wall was peeled off.
[0147]
(Examples 25 to 28 and Comparative Examples 7 and 8)
About each mixed solvent produced by mixing the organic solvent in the ratio shown in Table 2, the wettability was evaluated for the blue plate glass (# 0050) in the same manner as in Examples 1 to 7 and Comparative Examples 1 and 2. . However, DCr: diethyl carbitol, CrAc: carbitol acetate, BCA: butyl carbitol acetate, and Examples 25, 26, 27, and 28 are solvents having the same composition as Examples 8, 9, 10, and 11, respectively. In Comparative Examples 7 and 8, a solvent having the same composition as Comparative Examples 3 and 4 was used. Similarly, a coating material for forming an insulating film was prepared, and an insulating film was formed on the soda glass in the same manner as in Examples 18 to 24 and Comparative Examples 5 and 6. The effect of was evaluated. These results are shown in Table 7.
[0148]
[Table 7]

[0149]
As is clear from Table 7, the dielectric layers prepared from the insulating film forming paints of Examples 25 and 26 had no voids or pinholes and had good withstand voltage characteristics.
[0150]
The dielectric layers produced from the insulating film forming paints of Examples 27 and 28 are free of voids and pinholes and have a withstand voltage characteristic sufficient for practical use even when the substrate is not processed. However, the dielectric layer has further improved withstand voltage characteristics by performing UV cleaning.
[0151]
The dielectric layers produced from the insulating film-forming paints of Comparative Examples 7 and 8 both had voids and pinholes, and were somewhat inferior in withstand voltage characteristics.
[0152]
As is clear from Table 7, the address electrode protective film prepared from the insulating film-forming paints of Examples 25 to 28 has no defects such as voids and pinholes, and is a protective film. As a sufficient effect.
[0153]
On the other hand, the address electrode protective film prepared from the insulating film forming paints of Comparative Examples 7 and 8 was insufficient as a protective film because voids and pinholes were generated.
[0154]
Further, as is apparent from Table 7, the partition walls produced from the insulating film forming paints of Examples 25 and 26 are free from defects such as voids and pinholes, and a part of the partition walls is made of glass. There was no peeling from the substrate. In the partition walls produced from the insulating film forming paints of Examples 27 and 28, no voids or pinholes were generated, but the partition walls sometimes peeled off. However, the occurrence of separation of the partition walls was suppressed by performing UV cleaning.
[0155]
On the other hand, in the address electrode protective film prepared from the insulating film forming paints of Comparative Examples 7 and 8, voids and pinholes were generated, and there were places where the partition walls were not formed, and some of the partition walls were peeled off.
[0156]
【The invention's effect】
As described above, the coating material for forming an insulating film of the present invention has good wettability with any of a glass compound (such as a glass substrate), a metal compound (such as an Ag electrode), and a ceramic compound (such as an ITO film). An organic solvent having a contact angle with the material of less than 5 ° is used as a main solvent, and its abundance ratio in all the solvents is set to 50% by weight or more, so that the glass substrate, Ag electrode, and ITO film all have good wettability. As a result, it is possible to obtain an insulating film-forming coating material that does not generate repellency or voids. Therefore, by forming the insulating layer using the insulating film-forming paint of the present invention, it is possible to provide a plasma display panel or the like that is free from voids and pinholes and has excellent withstand voltage.
[0157]
In addition, by using the insulating film-forming paint of the present invention, the dielectric layer of the front glass substrate of the plasma display panel, the dielectric layer of the rear glass substrate, or the partition walls of the rear glass substrate can be formed at a high yield. A plasma display panel can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the structure of a plasma display panel.
FIG. 2 is an explanatory diagram of a method for measuring a contact angle.
[Explanation of symbols]
1 Surface glass substrate
2 Back glass substrate
3 Display electrodes
4 Transparent electrodes
5 Address electrodes
6 phosphor
7 Surface dielectric layer
8 Back dielectric layer
9 Bulkhead
10 MgO film

Claims (5)

And inorganic fine particles child, a binder resins, a coating material having a contact angle with respect to an electrode formed on one surface side of the glass substrate and a glass substrate having containing a Solvent are both less than 5 ° of the glass substrate A method for producing a substrate for a plasma display panel , wherein the glass substrate is coated on one surface side and heat-treated on the glass substrate coated with the paint . The solvent is 50% by mass of at least one solvent selected from diethyl carbitol, dipropylene glycol-n-propyl ether, tripropylene glycol monomethyl ether, diethyl cellosolve, carbitol acetate, dibutyl cellosolve and propylene glycol diacetate. The manufacturing method of the substrate for plasma display panels of Claim 1 contained above . The method for producing a substrate for a plasma display panel according to claim 1 or 2, comprising 10 to 95% by mass of the inorganic fine particles, 1 to 20% by mass of the binder resin, and 4 to 85% by mass of the solvent . The method for manufacturing a substrate for a plasma display panel according to claim 1, wherein the inorganic fine particles have an average particle size of 0.1 to 10 μm. The method for manufacturing a substrate for a plasma display panel according to claim 1, wherein the glass substrate is subjected to an ultraviolet cleaning process.

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