JP4432367B2 - Display panel - Google Patents

Description

【００４８】
次いで、透明基板１２に例えば窒素ガスといった不活性ガスを吹き付けて、シラザン系溶液の溶媒を蒸発させることで、シラザン化合物が画素電極１３，１３，…及び保護絶縁膜１８の表面に堆積した状態となる。
【００４９】
次いで、透明基板１２を１０〜３０分間放置すると、雰囲気中の水分によってシラザン化合物が加水分解・縮合するとともに画素電極１３，１３，…や保護絶縁膜１８と化学的に結合する。これにより、図８に示すように、フッ素を含む官能基が結合した縮合体からなる濡れ性可変層１４’が、画素電極１３，１３，…及び保護絶縁膜１８全体を覆うように一面に成膜される。濡れ性可変層１４’に含まれる縮合体は、次の一般式（２２）で表される。
【化２】

【００５０】
一般式（２２）において、Ｒｆは上述したようにフッ素を含む官能基であって撥液性を示す官能基であり、Ｘはシラザン化合物と結合した画素電極１３の原子若しくは原子団、保護絶縁膜１８の原子若しくは原子団、画素電極１３若しくは保護絶縁膜１８の表面と結合したシラザン化合物の一部の原子若しくは原子団、又は、化学構造式（２１）におけるＮＨ基を置換した基を構成する原子若しくは原子団のいずれかであり、ｎは１００以上の整数である。シラザン化合物が一般式（２０）で表されるシラザンオリゴマーの場合には、ＲｆはＣ₈Ｆ₁₇Ｃ₂Ｈ₄となり、ＸがＯとなる。シラザン化合物は活性が高く、画素電極１３，１３，…及び保護絶縁膜１８にも吸着しやすいから、濡れ性可変層１４’が画素電極１３，１３，…及び保護絶縁膜１８の表面に化学吸着した状態で成膜される。この濡れ性可変層１４’は所謂単分子層であり、濡れ性可変層１４’ではシラザン化合物の単分子ユニットにおける主鎖であるＲｆ−Ｓｉ−Ｘ−基又はＲｆ−Ｓｉ−基が、画素電極１３，１３，…及び保護絶縁膜１８の表面に対して略垂直方向に配列するとともに隣接する単分子ユニットのＳｉが、画素電極１３，１３，…及び保護絶縁膜１８の表面に沿った方向に対して加水分解により酸素をエーテル結合の状態で縮合されている。つまり、シラザン化合物は、画素電極１３，１３，…及び保護絶縁膜１８の表面の面方向に縮合されるとともに、画素電極１３，１３，…及び保護絶縁膜１８の表面に形成された、単分子ユニットにおける主鎖であるＲｆ−Ｓｉ−Ｘ−基又はＲｆ−Ｓｉ−基の上方に、更に単分子ユニットにおける主鎖Ｒｆ−Ｓｉ−Ｘ−基又はＲｆ−Ｓｉ−基が積み重なるということが殆どなくなる。このため、濡れ性可変層１４’の厚さは、実質的に単分子ユニットにおける主鎖（ここでは縮合体としての側鎖に相当。）であるＲｆ−Ｓｉ−Ｘ−基又はＲｆ−Ｓｉ−基の長さに等しくなる。またこの濡れ性可変層１４’は、各単分子ユニットにおける主鎖の中のフッ素を含む官能基Ｒｆが濡れ性可変層１４’の表面側に配置するように縮合されているから、表面では各官能基Ｒｆの撥液性によって有機化合物含有液に対して撥液性を示す。
【００５１】
（５）第二の洗浄工程
次いで、透明基板１２を大気中に放置した後に、透明基板１２の表面１２ａ側をｍ−キシレンヘキサフロイド液（シラザン系溶液の溶媒と同じ液）ですすぐことで、画素電極１３，１３，…及び保護絶縁膜１８の表面に堆積した未反応のシラザン化合物を洗い流す。
【００５２】
（６）露光工程
次いで、図９に示すように、透明基板１２の表面１２ａ側にフォトマスク基板４０を対向させた状態でフォトマスク基板４０に活性光線を透過させて、濡れ性可変層１４’を部分的に照射する。このフォトマスク基板４０によって、活性光線は、濡れ性可変層１４’のうち画素電極１３，１３，…に重なる領域及び画素電極１３，１３，…の配列範囲を囲繞する領域に入射する。これにより、濡れ性可変層１４’がパターン層１４となる。このときフォトマスク基板４０を濡れ性可変層１４’に当接させた状態で活性光線を照射しても良いし、フォトマスク基板４０を濡れ性可変層１４’から離した状態で活性光線を照射しても良いが、フォトマスク基板４０を濡れ性可変層１４’にできる限り近づけて軽く当接させると良い。活性光線としては、可視光線、紫外線、赤外線等があるが、後述する光触媒膜４３を励起する波長域の光である。
【００５３】
ここで、フォトマスク基板４０について図２１（ａ）、（ｂ）を用いて説明する。図２１（ａ）はフォトマスク基板４０の平面図であり、図２１（ｂ）はフォトマスク基板４０の断面図である。フォトマスク基板４０は活性光線を透過する透明基板４１を有し、この透明基板４１の一方の面４１ａにはマスク４２が保護絶縁膜１８に対応した網目パターンに形成されている。つまり、マスク４２には複数の開口部４２ａ，４２ａ，…が形成されており、複数の開口部４２ａ，４２ａ，…が囲繞領域１９，１９，…に対応するようにマトリクス状に配列されていることでマスク４２が網目状に形成されている。マスク４２によって囲繞される開口部４２ａの開口面積は、囲繞領域１９の面積よりやや大きくなっている。更に、フォトマスク基板４０の一方の面４１ａの外周部には、マスク４４が環状に形成されている。このマスク４４がマスク４２の外縁から離れてマスク４２を囲繞するように形成されており、マスク４２の外縁とマスク４４との間には環状の開口部４５が形成されている。そして、約０．２μｍ厚の光触媒膜４３がマスク４２及びマスク４４を被覆するように透明基板４１の一方の面４１ａ全体に成膜されており、光触媒膜４３が開口部４２ａ，４２ａ，…及び開口部４５を閉塞している。
【００５４】
マスク４２及びマスク４４は活性光線を反射したり、吸収したりし、活性光線を透過しないものである。光触媒膜４３は、樹脂などの透明なバインダに光触媒が分散したものであるか、又は、光触媒自体から形成されている。光触媒は、活性光線を受光することにより化学反応を促進する触媒として機能するものであって、光触媒としては、酸化チタン（ＴｉＯ₂）、酸化亜鉛（ＺｎＯ）、酸化スズ（ＳｎＯ₂）、チタン酸ストロンチウム（ＳｒＴｉＯ₃）、酸化タングステン（ＷＯ₃）、酸化ビスマス（Ｂｉ₂Ｏ₃）、酸化鉄（Ｆｅ₂Ｏ₃）が挙げられる。ここでは、酸化チタンを光触媒として用いる。酸化チタンは、アナターゼ型とルチル型があり本発明では何れも使用することができるが、アナターゼ型の酸化チタンは励起波長が３８０ｎｍ以下であるからより好ましい。
【００５５】
以上のようなフォトマスク基板４０を用いて透明基板４１の裏面４１ｂに活性光線を入射させる時には、図９に示すように開口部４２ａ，４２ａ，…を囲繞領域１９，１９，…にそれぞれ対向させ、更に画素電極１３，１３，…の全てが開口部４５よりも内側に収まるようにする。マスク４２及びマスク４４では活性光線が遮蔽されるが、開口部４２ａ，４２ａ，…及び開口部４５では活性光線が透過してマスク４２及びマスク４４の無い部分では光触媒膜４３を透過する。従って、濡れ性可変層１４’のうちマスク４２及びマスク４４に重なる領域には、活性光線が入射しないが、開口部４２ａ，４２ａ，…及び開口部４５に重なる領域には活性光線が入射する。
【００５６】
活性光線が光触媒膜４３を透過する際に活性酸素種（・ＯＨ）が生成される。濡れ性可変層１４’のうち活性光線が入射した領域には、光触媒膜４３を透過した活性酸素種が到達し、活性光線が入射しない領域には、マスク４２によって活性光線が遮蔽されるから活性酸素種が届かない。このように、光触媒膜４３に活性光線が入射することによって活性酸素種が発生し、発生した活性酸素種がフォトマスク基板４０と濡れ性可変層１４’との間の気相を拡散し、濡れ性可変層１４’に到達した活性酸素種によって濡れ性可変層１４’の化学構造を変化させる。なお、開口部４２ａの開口面積が囲繞領域１９の面積よりもやや大きいため、それぞれの囲繞領域１９よりもやや外側にも活性酸素種が到達する。
【００５７】
濡れ性可変層１４’のうちマスク４２及びマスク４４と重ならない領域は、光触媒の作用により生成された活性酸素種（・ＯＨ）により撥液性を示すＲｆ基が、親水性を示す水酸基に置換され、一般式（２３）に示すようになる。
【化３】

この領域が親液性領域１４ａ，１４ａ，…及び親液性領域１４ｃである。親液性領域１４ａ，１４ａ，…及び親液性領域１４ｃでは、フッ素を含む官能基（上記Ｒｆ）が分解・離脱し、水酸基に置換されるために、液体に対して親液性を示す。
【００５８】
更に、親液性領域１４ａにおいては、珪素と酸素からなる縮合体における主鎖が画素電極１３，１３，…の表面に沿った状態で形成され、且つ、撥液性を示すフッ素を含む官能基が水酸基に置換されるため、膜厚も単分子ユニットにおける主鎖（ここでは縮合体としての側鎖に相当。）であるＨＯ−Ｓｉ−Ｘ−基又はＨＯ−Ｓｉ−基の長さに等しく、１ｎｍ以下と非常に薄くすることができる。このため、画素電極１３及び対向電極１６に印加された電圧により画素電極１３から親液性領域１４ａを通過してＥＬ層１５に正孔のような電荷を注入することが可能となる。
【００５９】
一方、濡れ性可変層１４’のうちマスク４２及びマスク４４と重なる領域には、活性酸素種が到達しないから化学変化が起きず、依然撥液性を示す。この領域が、撥液性領域１４ｂ及び撥液性領域１４ｄである。撥液性領域１４ｂ及び撥液性領域１４ｄは、親液性領域１４ａ，１４ａ，…及び親液性領域１４ｃと連続して形成されているとともに親液性領域１４ａ，１４ａ，…及び親液性領域１４ｃよりもほぼフッ素を含む官能基Ｒｆの分だけ厚い。
【００６０】
（７）第三の洗浄工程
以上のように濡れ性可変層１４’を部分的に露光することによってパターン層１４を形成した後、速やかに透明基板１２全体特にパターン層１４の表面を純水でリンスする。パターン層１４の表面を純水でリンスする方法としては、純水の流水をパターン層１４の表面に流すことであっても良いし、純水の中に透明基板１２とともにパターン層１４を浸漬することであっても良い。また、パターン層１４を純水でリンスしている時間は特に限定されないが、リンスしている状態を所定時間保っているのが望ましい。パターン層１４の表面を純水でリンスしたら、純水を蒸発させてパターン層１４の表面を乾燥させる。乾燥させる雰囲気は大気で良い。
【００６１】
（８）ＥＬ層形成工程
パターン層１４の表面とともに透明基板１２が乾燥したら、それぞれの囲繞領域１９内にＥＬ層１５を成膜する。ＥＬ層１５，１５，…の成膜は、液滴吐出技術（インクジェット技術）を応用して行う。つまり、図１０に示すように、ＥＬ層１５の構成材料を含有した有機化合物含有液を吐出することのできるヘッド（ノズル）７０を透明基板１２に対向させて、駆動装置によって透明基板１２に対して相対的にヘッド７０を水平面に沿って移動させつつ、ヘッド７０が囲繞領域１９上に位置した時にヘッド７０から有機化合物含有液を液滴７１として一回又は複数回吐出する。これにより、有機化合物含有液の液滴が囲繞領域１９内においてパターン層１４上に着弾する。着弾した液滴が親液性領域１４ａで広がって膜になり、そしてその膜が固化することによって、ＥＬ層１５が形成される。また、有機化合物含有液を赤、緑、青の色ごとに準備し、ＥＬ層１５，１５，…の色を塗り分けても良い。
【００６２】
以上のように有機化合物含有液を塗布した場合でも、パターン層１４は囲繞領域１９内において親液性領域１４ａとなっているため、着弾した液滴が濡れやすいとともに滲みやすく、有機化合物含有液が囲繞領域１９内全体にいきわたる。また、囲繞領域１９よりやや外側にも活性光線が入射して囲繞領域１９よりも広い親液性領域１４ａが形成されているから、有機化合物含有液が確実に囲繞領域１９内全体にいきわたる。そのため、ＥＬ層１５が均等な厚さで成膜されるとともに、ＥＬ層１５とパターン層１４との間に剥離が生じることない。さらに、それぞれの親液性領域１４ａの周囲は撥液性領域１４ｂとなっているため、有機化合物含有液が撥液性領域１４ｂに滲むことがない。そのため、隣り合う二つの画素の有機化合物含有液同士が混ざり合うことがない。したがって、常に均等な厚さでＥＬ層１５，１５，…を成膜することができ、隣り合う二つの画素が互いに異なる発光色の有機化合物含有液の場合に色純度の高い発色ができる。
【００６３】
なお、ＥＬ層１５が積層構造である場合には、それぞれの層について有機化合物含有液を準備し、囲繞領域１９内にそれぞれの有機化合物含有液を順にノズルで吐出することでそれぞれの層を積層していく。例えば、ＥＬ層１５が正孔注入層、狭義の発光層からなる二層構造の場合には、正孔注入層の有機化合物含有液（正孔注入層を構成する有機化合物（例えば、導電性高分子であるＰＥＤＯＴ）と、ドーパントであるＰＳＳ）が水系分散媒に分散した分散液）を各囲繞領域１９内に吐出することで正孔注入層を成膜し、次いで、狭義の発光層の有機化合物含有液（ポリフルオレン系発光材料が例えばトルエン、キシレン、テトラリンといった有機溶媒に溶解した溶液）を各囲繞領域１９内に吐出することでＥＬ層１５を成膜する。この場合でも、パターン層１４のうち各親液性領域１４ａでは、正孔注入層の有機化合物含有液がなじみ、撥液性領域１４ｂでは正孔注入層の有機化合物含有液がはじかれる。
【００６４】
（９）対向電極形成工程
ＥＬ層１５，１５，…を液滴吐出法で成膜したら、塗布した有機化合物含有液の溶媒・分散媒を乾燥させる。次いで、蒸着やスパッタ等のＰＶＤ法及びＣＶＤ法といった成膜方法によって、ＥＬ層１５，１５，…を被覆するようにして対向電極１６を成膜するとともに対向電極１６の端子１６ａを引き回し配線１７に接続する（図１１、図１２）。ここで、平面視して親液性領域１４ｃの外縁１４ｆよりも内側に対向電極１６全体が配置されるように、対向電極１６を成膜する。またトランジスタ２１のドレイン電極２７やゲート電極２２に信号を出力する配線の端子が、外部回路と接続するために撥液性領域１４ｄの外側で露出している。これら端子群は撥液性領域１４ｄの外側において、保護絶縁膜１８及び親液性領域１４ｃ、又は保護絶縁膜１８、親液性領域１４ｃ及びゲート絶縁膜２３に形成された、図示しないコンタクトホールによって露出させてもよい。そして、対向電極１６の端子１６ａは、保護絶縁膜１８及び撥液性領域１４ｂに形成されたコンタクトホール２９により露出された引き回し配線１７の一端１７ａと接続している（図１２（ｃ））。引き回し配線１７の他端１７ｂは、撥液性領域１４ｄより外側の保護絶縁膜１８及び撥液性領域１４ｂにおいて露出されている。このように引き回し配線１７によって対向電極１６が撥液性領域１４ｄ上を遮ることがないので撥液性領域１４ｄが連続した枠の形状で露出できるとともに外部回路が撥液性領域１４ｄの外縁１４ｆで対向電極１６と接続することが可能となる。外部回路との接続のためのこれらのコンタクトホール群は必要に応じて一括して形成されてもよい。また対向電極１６を成膜しても、ＥＬ層１５が囲繞領域１９内全体にいきわたって形成されているから、対向電極１６が直接画素電極１３に接触することもなく、対向電極１６と画素電極１３がショートすることがない。
【００６５】
（１０）水分遮断シート接着工程
次いで、図１３、図１４に示すように、重合、架橋前の樹脂からなる接着剤層８４’、遮蔽層８５、ナイロン層８６、保護樹脂層８７の順に積層してなる水分遮断シート８１を準備する。ここで、水分遮断シート８１の面積が対向電極１６の面積以上となり、水分遮断シート８１の外縁の形状が親液性領域１４ｃの内縁１４ｅに囲まれた領域の形状よりも大きく、且つ、親液性領域１４ｃの外縁１４ｆに囲まれた領域の形状よりも小さくなるように、水分遮断シート８１を準備する。この水分遮断シート８１で対向電極１６全体を被覆するようにして水分遮断シート８１の接着剤層８４’を対向電極１６に接着する。水分遮断シート８１を対向電極１６に接着するに際して、水分遮断シート８１の外周部を親液性領域１４ｃの内周部に重ねるとともに、更に親液性領域１４ｃの外周部を水分遮断シート８１から露出させる。そして、接着剤層８４’が重合、架橋して硬化すると、ポリエチレン、ポリプロピレン等の吸着層８４に変質する（図１５、図１６）。水分遮断シート８１を接着する時に水や酸素が生じる場合、この後十分乾燥させることで水や酸素を除去する。なお、接着剤層８４’の組成にもよるが、水分遮断シート８１を接着する時に水分遮断シート８１の接触面８１ａより広い面積のヘッド９１（図１４に図示）に水分遮断シート８１を付着させることによって水分遮断シート８１を加熱して、更に水分遮断シート８１を透明基板１２側に押し付けるのが望ましい。このようなヘッド９１により水分遮断シート８１全面を圧着できるので接着剤層８４’が対向電極１６等に隙間なく密着できる。
【００６６】
（１１）樹脂塗布工程
次いで、図１７、図１８に示すように、二液型エポキシ樹脂、熱硬化性エポキシ樹脂又は光硬化性樹脂等の硬化前の液状の樹脂を水分遮断シート８１の外周部にディスペンサ装置等を用いて塗布する。ここで、樹脂が水分遮断シート８１の外縁から外に広がって延出するようにして樹脂を塗布する。水分遮断シート８１の外縁から延出した液状の樹脂が親液性領域１４ｃの露出した部分全体に滲んで広がる。ところが、親液性領域１４ｃの外周には撥液性領域１４ｄがパターンニングされているため、液状の樹脂が親液性領域１４ｃの外縁１４ｆよりも外側には滲まない。これにより、液状の樹脂を堰き止めることができ、従来のようなリング枠部を形成する必要がない。また、水分遮断シート８１の外周部が親液性領域１４ｃの内周部に重なり、且つ水分遮断シート８１の厚さが２００μｍと極めて薄い構造であるため、水分遮断シート８１と親液性領域１４ｃとの段差にまで、つまり図１８に示された入隅９０にまで樹脂が流れ込むから、その部分に気泡が残留することがない。そのため、有機ＥＬ素子１１，１１，…をより良く密閉することができる。
【００６７】
その後、塗布した樹脂が重合、架橋して硬化すると、その塗布した樹脂が樹脂シール８２になる。樹脂シール８２生成時に水や酸素が生じる場合、この後十分乾燥させることで水や酸素を除去する。このように形成された樹脂シール８２によって水分遮断シート８１とその下の部材との隙間を埋めて、隙間からの水や酸素の浸入を抑制することができる。
【００６８】
（１２）ガスバリア薄膜成膜工程
次いで、スパッタリング法、ＰＶＤ法又はＣＶＤ法によって透明基板１２の表面側一面、つまり、水分遮断シート８１及び樹脂シール８２全体にガスバリア性の薄膜８３を成膜する（図１９、図２０）。ここで、その薄膜８３がＡｌの場合には、蒸着法によって成膜し、その薄膜８３がＡｌ₂Ｏ₃の場合には、スパッタリング法によって成膜する。スパッタリング法によりガスバリア薄膜８３を形成する場合、樹脂シール８２の表面にシワが発生しておりガスバリア薄膜８３の膜厚が厚くなるほどシワが細かくなっているので、ガスバリア薄膜８３の応力を抑えるためにガスバリア薄膜８３の膜厚が３０００Å以下となるように成膜するのが望ましい。なお、金属微粒子を含む約２００℃のキャリアガスを水分遮断シート８１及び樹脂シール８２に吹き付けることで、ガスバリア薄膜８３を成膜しても良い。
【００６９】
ところで、仮に樹脂シール８２を形成せずにガスバリア薄膜８３を形成した場合には、水分遮断シート８１の外周部の段差によってガスバリア薄膜８３が水分遮断シート８１の外縁で途切れる恐れがある。しかしながら、本実施形態では、パターン層１４との接触面での傾斜角αが７５°未満になるように樹脂シール８２が形成されているため、水分遮断シート８１の段差による急峻な部分がなくなるので、数千Å程度の薄いガスバリア薄膜８３であっても途切れずに成膜することができる。また、二液型エポキシ樹脂又は熱硬化性エポキシ樹脂を硬化して樹脂シール８２を形成した場合には、重合生成後の経時的な樹脂シール８２の縮小率が小さいので、その後に被覆するガスバリア薄膜８３が樹脂シール８２の収縮により生ずる物理的応力のために皺を生じてしまうことがない。
【００７０】
以上のように製造された有機ＥＬ表示パネル１では、画素回路が信号線５１及び走査線５２を介して入力した信号に従って有機ＥＬ素子１１に電流を流す。有機ＥＬ素子１１では、画素電極１３からＥＬ層１５へ正孔が注入され且つ対向電極１６からＥＬ層１５へ電子が注入されることで、電流が流れる。そして、ＥＬ層１５において正孔及び電子が輸送されて、ＥＬ層１５にて正孔及び電子が再結合することによってＥＬ層１５で発光する。画素電極１３，１３，…及び透明基板１２が透明であるため、ＥＬ層１５で発した光は透明基板１２の裏面１２ｂから出射し、裏面１２ｂが表示面となる。
【００７１】
以上のように、本実施の形態では、シラザン化合物を加水分解・縮合させることで濡れ性可変層１４’を成膜し、珪素と酸素で構成された縮合体としての主鎖が画素電極１３，１３，…及び保護絶縁膜１８の表面に沿った状態で全面に形成され、各囲繞領域１９内において親液性領域１４ａの実質的な厚さが、濡れ性可変層１４’の単分子ユニットにおける主鎖からフッ素を含む官能基Ｒｆを除く厚さとなり非常に薄い。従って、画素電極１３とＥＬ層１５との間にパターン層１４が介在してもパターン層１４の絶縁性を無視することができ、画素電極１３からＥＬ層１５へ正孔が注入されることが阻害されない。
【００７２】
また、本実施形態では、濡れ性可変層１４’内に光触媒を含有させないで、フォトマスク基板４０を通じて濡れ性可変層１４’に活性酸素種を照射することで、濡れ性可変層１４’を部分的に反応させている。濡れ性可変層１４’のうち活性光線の照射された領域が親液性領域１４ａになり、画素電極１３からＥＬ層１５へ正孔が注入されることは阻害されないとともに、パターン層１４がＥＬ層１５に化学的に影響を与えることもない。
【００７３】
また、濡れ性可変層１４’のうち活性光線の照射された領域が親液性領域１４ａになり、親液性領域１４ａでは有機化合物含有液が濡れやすいから、ＥＬ層１５が囲繞領域１９全体にいきわたって滲みやすい。これによりＥＬ層１５が囲繞領域１９全体にいきわたって均一に成膜されているから、ゲート電極１３と対向電極１６の間でショートが生じない。また、ＥＬ層１５とパターン層１４との間に剥離が生じにくいから、発光したＥＬ層１５にダークスポットが発生しにくい。
【００７４】
また、水分遮断シート８１を対向電極１６に接着し、水分遮断シート８１の外周部に樹脂を塗布することで、有機ＥＬ素子１１，１１，…が封止される。ここで、水分遮断シート８１によって有機ＥＬ素子１１，１１，…の上面からの水及び酸素を十分遮蔽することができる。更に、樹脂シール８２が水分遮断シート８１の外周縁から延出するように形成されているので、水分遮断シート８１の界面でも、その外側を樹脂シール８２によって水や酸素の浸入を抑制することができる。
【００７５】
また、ＥＬ層形成工程では、パターン層１４の濡れ性のパターンを用いて有機化合物含有液の滲みを制御して、ＥＬ層１５，１５，…をパターニングしている。また、樹脂塗布工程では、パターン層１４の濡れ性のパターンを樹脂シール８２の樹脂に堰き止めに用いている。このようにパターン層１４をＥＬ層１５のパターンニングと樹脂の堰き止めに兼用しているので、有機ＥＬパネルの製造コストの削減を図ることができる。また、従来のようにリング枠部を形成せずとも、樹脂シール８２の樹脂を堰き止めることができるので、リング枠部の形成にかかるコストを削減することができる。さらにＥＬ層１５が所定の領域に成膜されるための親液性領域１４ａのパターニングと一括して撥液性領域１４ｄを形成できるので、生産性を向上することができる。
【００７６】
また、場合によってはガスバリア薄膜８３には厚さ方向にピンホールが生じることがあるが、対向電極１６上には水分遮断シート８１が設けられているので、ガスバリア薄膜８３にピンホールが発生した場合であっても、水分遮断シート８１が水や酸素を吸着して遮断するので有機ＥＬ素子１１，１１，…に水や酸素が到達することを抑制できる。
【００７７】
なお、本発明は上記実施の形態に限定されることなく、本発明の趣旨を逸脱しない範囲において、種々の改良並びに設計の変更を行っても良い。
【００７８】
例えば、上記実施形態の有機ＥＬ表示パネル１は自発光式であるため、ページプリンタといった画像形成装置の線走査機構に用いることができる。
また、上述の説明では、カソードである対向電極１６が全ての有機ＥＬ素子１１，１１，…について共通しているが、画素電極１３をカソードとして用いることによって有機ＥＬ素子１１ごとにカソードをパターンニングしても良い。画素電極１３のＥＬ層１５との界面を電子注入性に優れた低仕事関数の材料を含ませ、下層を画素電極１３のシート抵抗を小さくするために電気抵抗率の低い材料を含むようにしてもよい。このとき対向電極１６はアノードとなり、ＥＬ層１５，１５，…は適宜画素電極１３との界面が電子輸送性の層であり、対向電極１５との界面が正孔輸送性の層であることが好ましい。そして、有機ＥＬ表示パネル１の表示面を透明基板１２側としてもよく、水分遮断シート８１及びガスバリア薄膜８３を透明にして、ガスバリア薄膜８３側としてもよい。また、板状の透明基板１２の代わりにシート状の透明なフィルム基板を用いても良い。
【００７９】
また、上述の説明では液滴吐出法によって複数のＥＬ層１５，１５，…をパターニングしていた。しかしながら、パターン層１４では親液性領域１４ａ，１４ａ，…がマトリクス状にパターニングされているため、有機化合物含有液をパターン層１４に塗布して透明基板１２を回転させること（スピンコート法）によって、複数のＥＬ層１５，１５，…をマトリクス状にパターニングすることができる。また、パターン層１４の親液性と撥液性のパターニングを利用して、ディップコート法又はダイコート法によって複数のＥＬ層１５，１５，…をマトリクス状にパターニングしても良い。更には、平版印刷法、凹版印刷法、凸版印刷法、その他の印刷法を用いて複数のＥＬ層１５，１５，…をマトリクス状にパターニングしても良い。
【００８０】
また、上述の説明ではディップコート法によって濡れ性可変層１４’を成膜したが、スピンコート法、刷毛塗り法によって濡れ性可変層１４’を成膜しても良い。
【００８１】
また、上述の説明では濡れ性可変層１４’に光触媒が含まれていないが、光触媒を含有したシラザン系溶液を塗布することによって濡れ性可変層１４’に光触媒を含有させても良い。この場合には、フォトマスク基板４０に光触媒膜４３を設けなくても良い。
【００８２】
また、フッ素を含む官能基を有するシラン化合物として、シラザン化合物を挙げたが、シランカップリング剤（加水分解縮合可能なフルオロアルキル基含有珪素化合物）といった他のシラン化合物やその他の撥液性を示す官能基でもよく、置換される官能基は水酸基以外の親液性の官能基であっても良い。
【００８３】
また、上述の説明では、水分遮断シート８１が吸着層８４、遮蔽層８５、ナイロン層８６、保護樹脂層８７からなる四層構造であったが、水分遮断シート８１が順に吸着層８４、遮蔽層８５、保護樹脂層８７からなる三層構造であっても良い。
【００８４】
また、保護絶縁膜成形工程の後であって第一の洗浄工程の前に、図２２に示すように保護絶縁膜１８に重なるようにして網目状の仕切り壁２０をパターニングしても良い。仕切り壁２０の幅は、透明基板１２に近づくにつれて大きく、保護絶縁膜１８の幅より狭い。仕切り壁２０は、絶縁性を有しており、ポリイミド樹脂、ノボラック樹脂、アクリル樹脂等といった樹脂で形成されている。
【００８５】
また、上述の説明では樹脂塗布工程において水分遮断シート８１の外周部に樹脂を塗布したが、水分遮断シート８１全体を被覆するように樹脂を塗布しても良い。この場合でも、水分遮断シート８１の外周縁から樹脂を延出するようにして塗布し、図２３に示すように、親液性領域１４ｃ上にも樹脂を流し込む。この場合でも、撥液性領域１４ｄによって樹脂が堰き止められる。
【００８６】
また、上述の説明ではガスバリア薄膜成膜工程においてガスバリア薄膜８３によって水分遮断シート８１全体を被覆したが、図２４に示されるように水分遮断シート８１の中央部が露出するようにガスバリア薄膜８３を成膜しても良い。この場合では、ガスバリア薄膜８３を環状に形成し、ガスバリア薄膜８３で樹脂シール８２を被覆する。
【００８７】
また、上述の説明では封止性の観点から水分遮断シート８１を対向電極１６に重ねて接着したが、その工程を省略しても良い。但し、図２５に示すように、樹脂塗布工程では、対向電極１６全体を被覆するように樹脂を流し込んで更に親液性領域１４ｃにも樹脂が重なるように樹脂を流し込む。その後は、樹脂シール８２全体を被覆するようにガスバリア薄膜８３を成膜する。
【００８８】
【発明の効果】
本発明の表示パネルによれば、パターン層が発現する撥液性によって容易に封止樹脂の流動を制限しているので、所定の領域内に封止樹脂を形成することができる。
そして本発明の表示パネルの製造方法によれば、パターン層形成工程によって、立体的な高さを持つ壁としての枠部を形成することなしに樹脂被膜工程で被膜される樹脂の流動を制限することができる。特に濡れ性可変層の第三領域に活性光線を照射することでの濡れ性を簡易に向上することができる。そして、第一領域には活性光線が照射されていないから濡れ性が低いので、第三領域に重ねるように樹脂を塗布すると、第三領域に塗布した樹脂を第一領域の濡れ性の低い領域によって堰き止めることができる。
また、第二領域を複数離間するように設け、各第二領域に活性光線を照射することで各第二領域の濡れ性が向上する。そして、各第二領域に有機化合物含有液を塗布すると、有機化合物含有液が第二領域ではなじみやすいので、有機化合物含有液が各第二領域全体に滲み、ＥＬ層の成膜不良を抑えることができる。また、塗布された有機化合物含有液は第二領域では滲み、それぞれの第二領域の周囲でははじくから、隣り合う第一電極つまり隣り合う第一電極で有機化合物含有液が混ざることもなくなる。また、第一電極上で有機化合物含有液が滲むから、ＥＬ層の厚さが均一になる。
以上のように濡れ性可変層を形成し、濡れ性可変層のうちを部分的に照射することで濡れ性のパターンが形成され、濡れ性可変層の濡れ性のパターンを用いてＥＬ層のパターニングを行い、更に濡れ性可変層の濡れ性のパターンを用いて樹脂を堰き止めている。このように濡れ性可変層の濡れ性のパターンを用いているので、従来のようなリング枠部を形成する必要がない。また、濡れ性可変層をＥＬ層のパターンニングと樹脂の堰き止めに兼用している。従って、有機ＥＬパネルの製造コストの削減を図ることができる。
【図面の簡単な説明】
【図１】図１は、本発明を適用した製造方法により製造された有機ＥＬ表示パネルを示した断面図である。
【図２】図２は、上記有機ＥＬ表示パネルを示した平面図である。
【図３】図３は、上記有機ＥＬ表示パネルの断面を拡大して示した図である。
【図４】図４は、上記有機ＥＬ表示パネルに形成されているパターン層を示した平面図である。
【図５】図５は、図１の領域５を拡大して示した図面である。
【図６】図６は、上記有機ＥＬ表示パネルを製造するための一工程を示した図面である。
【図７】図７は、図６の続きの工程を示した図面である。
【図８】図８は、図７の続きの工程を示した図面である。
【図９】図９は、図８の続きの工程を示した図面である。
【図１０】図１０は、図９の続きの工程を示した図面である。
【図１１】図１１は、図１０の続きの工程を示した図面である。
【図１２】図１２（ａ）は図１１中のＡ−Ａ線断面を示した図面であり、図１２（ｂ）は図１１中のＢ−Ｂ線断面を示した図面であり、図１２（ｃ）は図１１中のＣ−Ｃ線断面を示した図面である。
【図１３】図１３は、図１１の続きの工程を示した図面である。
【図１４】図１４（ａ）は図１３中のＡ−Ａ線断面を示した図面であり、図１４（ｂ）は図１３中のＢ−Ｂ線断面を示した図面であり、図１４（ｃ）は図１３中のＣ−Ｃ線断面を示した図面である。
【図１５】図１５は、図１３の続きの工程を示した図面である。
【図１６】図１６（ａ）は図１５中のＡ−Ａ線断面を示した図面であり、図１６（ｂ）は図１５中のＢ−Ｂ線断面を示した図面であり、図１６（ｃ）は図１５中のＣ−Ｃ線断面を示した図面である。
【図１７】図１７は、図１５の続きの工程を示した図面である。
【図１８】図１８（ａ）は図１７中のＡ−Ａ線断面を示した図面であり、図１８（ｂ）は図１７中のＢ−Ｂ線断面を示した図面であり、図１８（ｃ）は図１７中のＣ−Ｃ線断面を示した図面である。
【図１９】図１９は、図１７の続きの工程を示した図面である。
【図２０】図２０（ａ）は図１９中のＡ−Ａ線断面を示した図面であり、図２０（ｂ）は図１９中のＢ−Ｂ線断面を示した図面であり、図２０（ｃ）は図１９中のＣ−Ｃ線断面を示した図面である。
【図２１】図２１は上記有機ＥＬ表示パネルを製造するに際して使用するフォトマスク基板を示した図面であり、（ａ）は平面図であり、（ｂ）は断面図である。
【図２２】図２２は、図１とは別の有機ＥＬ表示パネルを示した断面図である。
【図２３】図２３は、図１、図２２とは別の有機ＥＬ表示パネルを示した断面図である。
【図２４】図２４は、図１、図２２、図２３とは別の有機ＥＬ表示パネルを示した断面図である。
【図２５】図２５は、図１、図２２、図２３、図２４とは別の有機ＥＬ表示パネルを示した断面図である。
【図２６】従来の有機ＥＬ表示パネルの封止構造を示した断面図である。
【符号の説明】
１ … 有機ＥＬ表示パネル
１１ … 有機ＥＬ素子
１２ … 透明基板
１３ … 画素電極
１４ … パターン層
１４’ … 濡れ性可変層
１４ａ … 第一親液性領域
１４ｂ … 第一撥液性領域
１４ｃ … 第二親液性領域
１４ｄ … 第二撥液性領域
１５ … ＥＬ層
１６ … 対向電極
８１ … 水分遮断シート
８２ … 樹脂シール
８３ … ガスバリア薄膜
８４ … 吸着層
８５ … 遮蔽層[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a display panel in which a display element is formed on a substrate.RelatedTo do.
[0002]
[Prior art]
Patent Document 1 describes a sealing process in a method for manufacturing an LED display. Briefly describing the technique described in Patent Document 1, a plurality of LED chips are surface-mounted on a substrate in a matrix shape, and a ring-shaped frame portion is formed on the substrate so as to surround the plurality of LED chips. . This ring-shaped frame portion is made of a fluororesin. And resin is inject | poured into the area | region enclosed by the ring-shaped frame part, and the resin is covered with this ring-shaped frame part, A several LED chip is coat | covered with this resin. Thereby, a plurality of LED chips are sealed.
[0003]
On the other hand, an organic EL (Electro Luminescence) element has been developed as a kind of LED as a self-luminous element. An organic EL element has a laminated structure in which an anode, an EL layer, and a cathode are laminated in this order. An organic EL display panel in which such organic EL elements are arranged in a matrix on a substrate as a pixel is realized. ing. In manufacturing an LED display, it is necessary to mount a plurality of LED chips manufactured in advance on a substrate, and thus there is a limit in manufacturing a display with high resolution. On the other hand, in manufacturing an organic EL display panel, a plurality of organic EL elements are combined by appropriately performing a film forming process such as vapor deposition on the substrate, a mask process such as a photolithography method, and a thin film shape processing process such as etching. Since the patterning is performed on the substrate, it is possible to provide a display with higher resolution than the LED display.
[0004]
However, since organic EL elements are easily degraded by moisture, oxygen, etc. in the outside air, it is necessary to seal them with a sealing structure. Therefore, a plurality of organic EL elements are patterned as in the technique described in Patent Document 1. In some cases, the sealing film is formed as a three-dimensional wall that surrounds the range.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-294498
[0006]
[Description of the Invention]
  However, in order to form such a sealing film, a wide ring-shaped frame part surrounding a plurality of organic EL elements must be used, and the cost increases and the process of forming the ring-shaped frame part Has caused the problem of increasing. And in order to make it high enough to dam up a sealing film in such a ring-shaped frame part, when forming a ring-shaped frame part by patterning by the photolithographic method, the higher the ring-shaped frame part, There is a problem that photo etching takes time. On the other hand, if the ring-shaped frame portion is simply formed by printing or the like in order to shorten the manufacturing time, it is difficult to finely adjust the position of the substrate 101 and the frame portion 103 as shown in FIG. In consideration of the above, the design should be such that the ratio of the area of the non-display area A1 to the display area A0 in which the organic EL element 102 in the frame 103 can emit light increases.
  In addition, when the sealing film 104 is thickened to obtain a sufficient sealing effect or the viscosity of the resin that becomes the sealing film 104 is increased, voids 105 are likely to be formed at the corners of the frame portion 103, and this gap Since the contact area between the sealing film 104 and the substrate 101 is reduced, the sealing effect is reduced. Further, since the distance D1 from the sealing film 104 in contact with the substrate 101 to the organic EL element 102 is short, the gap 105 Oxygen or moisture easily enters the organic EL element 102 through the interface between the substrate 104 and the sealing film 104. In addition, the area of the contact portion 106 between the sealing film 104 and the frame portion 103 is reduced, oxygen and moisture in the outside air easily enter the gap 105, and the organic EL element 102 may be further deteriorated. is there.
  Accordingly, an object of the present invention is to provide a display panel that does not require a frame as a wall having a three-dimensional height.LeIs to provide.
[0007]
[Means for Solving the Problems]
  In order to solve the above problems, the invention according to claim 1 is a display panel,
  A substrate,
  A display element having a plurality of pixels arranged on the substrate;
  A pattern layer in which a region on the substrate around the display element exhibits liquid repellency;
  A sealing resin in which the shape of the outer edge is blocked by the liquid-repellent region of the pattern layer;
With,
The display element is covered with a moisture blocking sheet, and the moisture blocking sheet is covered with the sealing resin on the outer periphery thereof,
The moisture blocking sheet and the sealing resin are covered with a gas barrier thin film.It is characterized by that.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. Further, in the following description, “in plan view” means “seen in a direction perpendicular to the surface direction of the transparent substrate 12”.
[0012]
FIG. 1 is a sectional view of the entire organic EL display panel 1 to which the present invention is applied.
The organic EL display panel 1 includes a transparent substrate 12 having a property of transmitting light (hereinafter referred to as translucency) and a plurality of organic EL elements 11 (shown in FIG. 3) laminated on the transparent substrate 12. And a laminated structure 3 comprising a plurality of transistors 21 (shown in FIG. 3) and the like, a sealing structure 4 formed on the laminated structure 3 and encapsulating the plurality of organic EL elements 11 and the plurality of transistors 21, Is provided.
[0013]
The transparent substrate 12 is formed in a flat plate shape using borosilicate glass, quartz glass, other glass, PMMA, polycarbonate, or other resin.
[0014]
The laminated structure 3 will be described with reference to FIGS.
FIG. 2 is an enlarged plan view showing the laminated structure 3, and FIG. 3 is a cross-sectional view taken along the cutting line III-III shown in FIG.
[0015]
As shown in FIG. 2, when the laminated structure 3 is viewed in plan, the organic EL elements 11 as pixels are arranged in a matrix in the laminated structure 3, and the organic EL display panel 1 is arranged in an active matrix drive system in the laminated structure 3. Matrix display is performed. In the stacked structure 3, a region where the plurality of organic EL elements 11 are arranged in a matrix functions as a display element, and a region outside the display element is a non-light emitting portion. In the laminated structure 3, one pixel circuit is provided for one pixel (organic EL element 11). The pixel circuit inputs a signal from a peripheral driver (not shown) via the signal line 51 and the scanning line 52, turns on / off a current flowing through the organic EL element 11 according to the input signal, It is provided as an active element that keeps the light emission luminance of the organic EL element 11 constant by holding the current value during the light emission period. Each pixel circuit is composed of at least one transistor, and a capacitor may be added as appropriate. In FIG. 2, the pixel circuit is composed of two transistors 21 and 21 as an example. . FIG. 3 mainly shows an enlarged view of one pixel.
[0016]
As shown in FIGS. 2 and 3, a plurality of conductive scanning lines 52, 52,... Extending in the horizontal direction are formed on the surface 12 a of the transparent substrate 12. The scanning lines 52, 52,... Are arranged in parallel with each other at substantially equal intervals in plan view. The scanning lines 52, 52,... Are covered with a gate insulating film 23 formed on the entire surface 12a of the transparent substrate 12. A plurality of signal lines 51, 51,... Extending in the vertical direction are formed on the gate insulating film 23, and the signal lines 51, 51,. They are orthogonal to each other. The signal lines 51, 51,... Are also arranged in parallel with each other at substantially equal intervals in plan view.
[0017]
A plurality of transistors 21, 21,... Are formed on the surface 12 a of the transparent substrate 12. Each transistor 21 includes a gate electrode 22, a gate insulating film 23, a semiconductor film 24, impurity semiconductor films 25 and 26, a drain electrode 27, and a source electrode 28, and is a MOS field effect thin film transistor in which these are stacked. is there. The gate insulating film 23 is formed on the entire surface 12a of the transparent substrate 12, and is a layer common to all the transistors 21, 21,.
[0018]
.. Are covered with a protective insulating film 18. In plan view, the protective insulating film 18 is formed in a mesh shape so as to overlap the signal lines 51, 51,... And the scanning lines 52, 52,. When the protective insulating film 18 is formed in a mesh shape in a plan view, a plurality of surrounding regions 19, 19,... Surrounded by the protective insulating film 18 are arranged in a matrix on the transparent substrate 12. It is formed. The protective insulating film 18 is made of silicon oxide (SiO₂) And silicon nitride (SiN).
[0019]
The organic EL element 11 includes a pixel electrode 13 that is a first electrode that functions as an anode, an electroluminescence layer 15 (hereinafter abbreviated as EL layer 15) made of an organic compound, and a counter electrode 16 that is a second electrode that functions as a cathode. It is the laminated structure laminated | stacked in this order. The pixel electrode 13 is transparent to visible light and conductive, and has a relatively high work function. The pixel electrode 13 is formed of, for example, indium oxide, zinc oxide, tin oxide, or a mixture containing at least one of them (for example, tin-doped indium oxide (ITO), zinc-doped indium oxide).
[0020]
In plan view, the pixel electrodes 13, 13,... Are disposed in regions surrounded by the signal lines 51, 51,... And the scanning lines 52, 52,. The gate insulating films 23 are arranged in a matrix at intervals.
[0021]
In plan view, the pixel electrodes 13, 13,... Respectively correspond to the surrounding areas 19, 19,. In plan view, the area of the surrounding region 19 is smaller than the area of the pixel electrode 13, the surrounding region 19 is arranged inside the outer edge of the pixel electrode 13, and the outer peripheral portion of the pixel electrode 13 is a part of the protective insulating film 18. It overlaps with. In this example, the pixel electrode 13 is connected to the source electrode 28 of the transistor 21, but the pixel electrode 13 may be connected to another transistor or capacitor depending on the circuit configuration of the pixel circuit.
[0022]
On the pixel electrodes 13, 13,..., A pattern layer 14 is formed in common for all the organic EL elements 11, 11,. The pattern layer 14 is formed over the entire surface from the display area to the non-display area of the transparent substrate 12, and covers the protective insulating film 18 together with the pixel electrodes 13, 13,. FIG. 4 is a plan view showing the pattern layer 14 on the transparent substrate 12. As shown in FIGS. 3 and 4, the pattern layer 14 is adapted to the liquid in a region overlapping the pixel electrodes 13, 13,... And wets at a contact angle of 40 ° or less (hereinafter referred to as “parent”). Lyophilic region (electrode lyophilic region, second region) 14a, 14a,..., And the region overlapping the protective insulating film 18, the liquid is 50 °. It is patterned into a liquid repellent region 14b having a property of getting wet with the following contact angle (hereinafter referred to as “liquid repellency”). That is, in the pattern layer 14, the liquid repellent region 14b is formed in a mesh shape in plan view, and the lyophilic regions 14a, 14a,... Are arranged in a matrix so as to be surrounded by the liquid repellent region 14b. Is formed. In plan view, the area of the lyophilic region 14a is larger than the area of the surrounding region 19, and the entire surrounding region 19 is included in the lyophilic region 14a.
[0023]
In a plan view, the pattern layer 14 includes an annular lyophilic region (sealing) that collectively surrounds the plurality of pixel electrodes 13, 13,... Outside the range where the pixel electrodes 13, 13,. It is patterned into a lyophilic region for a resin stop (third region) 14c, and is further patterned into an annular liquid repellent region (first region) 14d surrounding the lyophilic region 14c.
[0024]
The lyophilic regions 14a, 14a,... And the lyophilic region 14c of the pattern layer 14 are very thin and have a thickness greater than 0.0 nm and less than or equal to 1 nm. In FIG. 4, reference numeral 14e is an inner edge of the lyophilic region 14c, and reference numeral 14f is an outer edge of the lyophilic region 14c.
[0025]
As shown in FIGS. 2 and 3, the EL layers 15, 15,... Are arranged in a matrix in plan view, and are formed on the lyophilic regions 14a, 14a,.
[0026]
Each EL layer 15 is a layer formed of a light emitting material that is an organic compound, and generates excitons by recombining holes injected from the pixel electrode 13 and electrons injected from the counter electrode 16. This layer emits light. Further, each EL layer 15 may be appropriately mixed with an electron transporting substance, may be appropriately mixed with a hole transporting substance, or may be mixed with an electron transporting substance and a hole transporting substance. Substances may be mixed as appropriate.
[0027]
Each EL layer 15 has a three-layer structure that becomes a hole transport layer, a light emitting layer in a narrow sense, and an electron transport layer in order from the pixel electrode 13, or a hole transport layer and a light emitting layer in a narrow sense in order from the pixel electrode 13. The layer structure may be a single layer structure composed of a light-emitting layer in a narrow sense, or a laminated structure in which an electron or hole injection layer is interposed between appropriate layers in these layer structures. Here, each EL layer 15 is laminated in the order of a hole transport layer made of PEDOT (polythiophene) which is a conductive polymer and PSS (polystyrene sulfonic acid) which is a dopant, and a light emitting layer in a narrow sense made of a polyfluorene-based light emitting material. This is a two-layer structure. The EL layer 15 is formed by applying an organic compound-containing liquid (that is, a wet application method). The organic compound-containing liquid is a liquid containing an organic compound constituting the EL layer 15 or a precursor thereof, and even if the organic compound constituting the EL layer 15 or a precursor thereof is dissolved in a solvent as a solute. Alternatively, a dispersion liquid in which the organic compound constituting the EL layer 15 or a precursor thereof is dispersed in a dispersion medium may be used.
[0028]
The counter electrode 16 is continuously formed so as to cover all the EL layers 15, 15. That is, in a plan view, there are all the lyophilic regions 14a, 14a,... Shown in FIG. 4 inside the outer edge of the region where the counter electrode 16 is formed. In plan view, the outer edge of the counter electrode 16 is inside the outer edge 14f of the lyophilic region 14c as shown in FIG.
[0029]
The cathode includes at least a material having a low work function, and is specifically formed of magnesium, calcium, lithium, barium, a rare earth element, or an alloy including at least one of these elements. Further, the cathode may have a laminated structure, for example, a laminated structure in which a film formed of a low work function material as described above is coated with a high work function and low resistivity material such as aluminum or chromium. good. Further, the cathode desirably has a light shielding property against visible light, and further desirably has a high reflectivity with respect to visible light emitted from the EL layer 15. In other words, the light utilization efficiency can be improved by the cathode acting as a mirror surface that reflects visible light.
[0030]
As described above, the pattern layer 14 and the counter electrode 16 are layers common to all the organic EL elements 11, 11,..., And the pixel electrode 13 and the EL layer 15 are independently provided for each organic EL element 11. Is formed.
[0031]
Next, the sealing structure 4 is demonstrated using FIG.1, FIG.3, FIG.5. Here, FIG. 5 is a cross-sectional view taken along the cutting line V-V shown in FIG. 4 and is an enlarged view of the region 5 of FIG.
The sealing structure 4 includes a moisture blocking sheet 81 provided on the counter electrode 16, a resin seal 82 formed in an annular shape so as to surround the moisture blocking sheet 81, and the moisture blocking sheet 81 and the resin seal 82. And a gas barrier thin film 83 covering the whole.
[0032]
The moisture blocking sheet 81 is formed of a material capable of preventing the permeation of moisture and oxygen in order to prevent the deterioration of the characteristics of the organic EL elements 11, 11,. In order to adhere to the surface of the counter electrode 16, it is made of a flexible material. As a material for forming the moisture blocking sheet 81, a laminate in which at least an olefin resin layer and a metal or alloy layer are laminated is preferably used.
[0033]
Specifically, the moisture blocking sheet 81 has a four-layer structure in which an adsorption layer 84, a shielding layer 85, a nylon layer 86, and a protective resin layer 87 are laminated in this order from the lower layer. The adsorption layer 84 is made of an olefin-based resin having a functional group that physically adsorbs water or oxygen, and easily adheres to the counter electrode 16. Examples of the olefin resin include polyethylene and polypropylene. The film thickness of the adsorption layer 84 is 20 μm to 100 μm. A moisture absorbent such as calcium oxide, barium oxide, magnesium sulfate may be added to the adsorption layer 84. Furthermore, an oxygen scavenger that chemically adsorbs oxygen, such as iron powder, may be added to the adsorption layer 84.
[0034]
The shielding layer 85 is made of a metal or an alloy and shields permeation of water and oxygen. Examples of the metal and alloy excellent in permeation-preventing property against water and oxygen include aluminum, nickel, titanium, aluminum alloy, nickel alloy, titanium alloy, and stainless steel. Here, the shielding layer 85 is made of aluminum. The thickness of the shielding layer 85 is 10 to 40 μm.
[0035]
The nylon layer 86 is made of nylon. A deoxidizing agent that chemically adsorbs oxygen, such as iron powder, may be added to the nylon layer 86, or a hygroscopic agent such as calcium oxide, barium oxide, or magnesium sulfate may be added. The film thickness of the nylon layer 86 is not particularly limited, but is 9 μm here.
[0036]
The protective resin layer 87 is made of a polyester resin such as polyethylene terephthalate. An oxygen-absorbing agent that chemically adsorbs oxygen such as iron powder may be added to the protective resin layer 87, or a moisture-absorbing agent such as calcium oxide, barium oxide, or magnesium sulfate may be added. The thickness of the protective resin layer 87 is not particularly limited, but is 12 μm here.
[0037]
In plan view, the outer edge of the moisture blocking sheet 81 substantially coincides with the outer edge of the counter electrode 16 so as to cover the entire counter electrode 16, or is outside the outer edge of the counter electrode 16. Furthermore, in plan view, the outer edge of the moisture blocking sheet 81 is included in the lyophilic region 14c of the pattern layer 14, and a part of the outer periphery of the moisture blocking sheet 81 is a part of the lyophilic region 14c. The outer peripheral part of the lyophilic region 14 c is exposed from the moisture blocking sheet 81. That is, in plan view, the outer edge of the moisture blocking sheet 81 is outside the inner edge 14e of the lyophilic region 14c as shown in FIG. 4, and is more than the outer edge 14f of the lyophilic region 14c as shown in FIG. Is also inside.
[0038]
The resin seal 82 is obtained by curing any one of a two-pack type epoxy resin, a thermosetting epoxy resin, and a photocurable resin (ultraviolet curable resin). The resin seal 82 is formed so as to cover the outer peripheral edge of the moisture blocking sheet 81 along the outer edge of the moisture blocking sheet 81. Further, the resin seal 82 extends from the outer edge of the moisture blocking sheet 81 and is also formed on the lyophilic region 14 c of the pattern layer 14. However, since the outer edge of the resin seal 82 is blocked by the liquid repellency of the liquid repellent region 14d, the resin seal 82 does not extend from the outer edge 14f of the lyophilic region 14c to the outer liquid repellent region 14d. . The resin seal 82 suppresses intrusion of water or oxygen into the interface between the moisture blocking sheet 81 and the pattern layer 14.
[0039]
The gas barrier thin film 83 is made of aluminum oxide or aluminum. The gas barrier thin film 83 covers the moisture blocking sheet 81 and the resin seal 82. The thickness of the gas barrier thin film 83 is preferably 0.0001 mm or more and 0.01 mm or less from the viewpoint of sealing properties and overall thinning. “Gas barrier property” refers to the property of shielding oxygen gas and water vapor without allowing oxygen gas and water vapor to pass through.
[0040]
Next, a method for manufacturing the organic EL display panel 1 will be described with reference to FIGS. Here, FIG. 6 to FIG. 8 are drawings showing a state in the same illustrated range as FIG. 3 in the manufacturing process. 9A is a diagram showing a state in the same illustrated range as FIG. 3 in the manufacturing process, and FIG. 9B is a diagram showing a state in the same illustrated range in FIG. 5 in the manufacturing process. is there. 10A is a plan view of the entire panel in the manufacturing process, and FIG. 10B is a view showing a state in the same drawing range as FIG. 3 in the manufacturing process. 11, 13, 15, 17, and 19 are plan views of the entire panel in the manufacturing process. FIGS. 12, 14, 16, 18, and 20 (a) are cross-sectional views taken along line AA in FIGS. 11, 13, 15, 17, and 19, respectively. FIG. 11 (b) is a cross-sectional view taken along line BB in FIGS. 11, 13, 15, 17, and 19, and FIG. 11 (c) is a cross-sectional view of FIG. 11, FIG. 13, FIG. FIG. 20 is a cross-sectional view taken along line CC in FIGS. 17 and 19.
[0041]
(1) Transistor / pixel electrode formation process
First, the signal lines 51, 51,... And the scanning lines 52 are appropriately performed by performing a thin film shape processing process such as a film forming process such as sputtering, PVD, and CVD, a mask process such as photolithography, and an etching process. , 52,... Are patterned and the pixel electrode 13 and the transistors 21, 21 are patterned on the surface 12a of the transparent substrate 12 for each pixel (FIG. 6). Here, when the pixel electrode 13 and the transistor 21 are formed by patterning, the resist is masked with a resist so that the source electrode 28 of the transistor 21 and the pixel electrode 13 are connected. Further, as shown in FIG. 12C, the lead-out wiring 17 of the counter electrode 16 is formed by patterning the same film as the drain electrode 27 and the source electrode 28 of the transistor 21.
[0042]
(2) Protective insulating film formation process
After forming the pixel electrodes 13, 13,... And transistors 21, 21,..., A film forming process such as sputtering, PVD, and CVD, a mask process such as photolithography, and a thin film shape processing process such as etching are performed. Thus, a mesh-like protective insulating film 18 is formed so as to surround the pixel electrodes 13, 13,. By forming the protective insulating film 18, the surrounding areas 19, 19,... Surrounded by the protective insulating film 18 are formed, and the pixel electrode 13 is exposed in each surrounding area 19 (FIG. 7).
[0043]
(3) First cleaning process
Next, the surface 12a side of the transparent substrate 12, that is, the exposed surfaces of the pixel electrodes 13, 13,... And the protective insulating film 18 is cleaned. The cleaning may be oxygen plasma cleaning under reduced pressure below atmospheric pressure, or ultraviolet / ozone cleaning. Thereafter, the exposed surfaces of the pixel electrodes 13,..., The protective insulating film 18, the back surface 12 b of the transparent substrate 12, and the like are washed with pure water. Next, an inert gas such as nitrogen gas is sprayed on the transparent substrate 12 to dry the transparent substrate 12.
[0044]
(4) Step of forming wettability variable layer
Next, a film made of a silane compound having a fluorine-containing functional group, particularly a silazane compound having a fluorine-containing functional group, among the silane compounds, is formed on the exposed surface of the pixel electrodes 13, 13,. Coating.
Specifically, the surface of the transparent substrate 12 is obtained by immersing the transparent substrate 12 in a solution containing a silazane compound having a functional group containing fluorine (hereinafter referred to as a silazane-based solution) and then pulling up the transparent substrate 12. A silazane solution is applied to the entire surface of the 12a side (dip coating method).
[0045]
Here, the “silazane compound having a functional group containing fluorine” is a compound having a Si—N—Si bond, and a functional group containing fluorine bonded to N or / and Si. The oligomer or polymer represented by Formula (1) is mentioned.
RfSi (NH)_3/2  ... (1)
In the general formula (1), Rf is a functional group containing fluorine.
The “functional group containing fluorine” includes a fluoroalkyl group, and examples thereof include functional groups represented by the following general formulas (2) to (19).
-(CH₂)_a(CF₂)_bCF_Three  ... (2)
-(CH₂)_a(CF₂)_bCF (CF_Three)₂  ... (3)
-(CH₂)_a(CF₂)_bC (CF_Three)_Three  (4)
-(CF₂)_aCF_Three  ... (5)
-(CF₂)_aCF (CF_Three)₂  (6)
-(CF₂)_aC (CF_Three)_Three  ... (7)
-(CF₂)_a(C (CF_Three)₂)_bCF_Three  ... (8)
-(CF₂)_a(C (CF_Three)₂)_bCF (CF_Three)₂  ... (9)
-(CF₂)_a(C (CF_Three)₂)_bC (CF_Three)_Three  (10)
-(CF₂)_a(C (CF_Three)₂)_b(CF₂)_cCF_Three  ... (11)
-(CF₂)_a(C (CF_Three)₂)_b(CF₂)_cCF (CF_Three)₂  (12)
-(CF₂)_a(C (CF_Three)₂)_b(CF₂)_cC (CF_Three)_Three  ... (13)
-(C (CF_Three)₂)_aCF_Three  ... (14)
-(C (CF_Three)₂)_aCF (CF_Three)₂  ... (15)
-(C (CF_Three)₂)_aC (CF_Three)_Three  ... (16)
-(C (CF_Three)₂)_a(CF₂)_bCF_Three  ... (17)
-(C (CF_Three)₂)_a(CF₂)_bCF (CF_Three)₂  ... (18)
-(C (CF_Three)₂)_a(CF₂)_bC (CF_Three)_Three  ... (19)
In general formulas (2) to (19), a, b, and c are all integers.
[0046]
Examples of the solvent for the silazane solution include a fluorine solvent.
[0047]
Here, as the silazane compound, a silazane oligomer (KP-801M: manufactured by Shin-Etsu Chemical Co., Ltd.) represented by the following general formula (20) and chemical structural formula (21) is used. In the dip coating step described above, the transparent substrate 12 is immersed for about one minute in a silazane-based solution (concentration: 3 wt%) obtained by dissolving the silazane oligomer as a solute in an m-xylene hexafluoride solvent.
C₈F₁₇C₂H_FourSi (NH)_3/2  ... (20)
[Chemical 1]

[0048]
Next, an inert gas such as nitrogen gas is blown onto the transparent substrate 12 to evaporate the solvent of the silazane solution, whereby the silazane compound is deposited on the surface of the pixel electrodes 13, 13,. Become.
[0049]
Next, when the transparent substrate 12 is left for 10 to 30 minutes, the silazane compound is hydrolyzed and condensed by moisture in the atmosphere, and chemically bonded to the pixel electrodes 13, 13,... And the protective insulating film 18. As a result, as shown in FIG. 8, the wettability variable layer 14 ′ made of a condensate bonded with a functional group containing fluorine is formed over the entire surface so as to cover the pixel electrodes 13, 13,. Be filmed. The condensate contained in the wettability variable layer 14 ′ is represented by the following general formula (22).
[Chemical 2]

[0050]
In the general formula (22), Rf is a functional group containing fluorine as described above and exhibiting liquid repellency, and X is an atom or atomic group of the pixel electrode 13 bonded to the silazane compound, a protective insulating film 18 atoms or atomic groups, some atoms or atomic groups of the silazane compound bonded to the surface of the pixel electrode 13 or the protective insulating film 18, or atoms constituting a group substituted with the NH group in the chemical structural formula (21) Or it is either an atomic group, and n is an integer of 100 or more. When the silazane compound is a silazane oligomer represented by the general formula (20), Rf is C₈F₁₇C₂H_FourAnd X becomes O. Since the silazane compound has high activity and is easily adsorbed to the pixel electrodes 13, 13,... And the protective insulating film 18, the wettability variable layer 14 ′ is chemically adsorbed on the surface of the pixel electrodes 13, 13,. In this state, the film is formed. This wettability variable layer 14 ′ is a so-called monomolecular layer, and in the wettability variable layer 14 ′, the Rf—Si—X— group or the Rf—Si— group, which is the main chain in the monomolecular unit of the silazane compound, is a pixel electrode. Are arranged in a substantially vertical direction with respect to the surface of the protective insulating film 18, and Si adjacent to the single molecular unit extends in a direction along the surfaces of the pixel electrodes 13, 13,. On the other hand, oxygen is condensed in an ether bond state by hydrolysis. That is, the silazane compound is condensed in the surface direction of the surface of the pixel electrodes 13, 13,... And the protective insulating film 18, and is a single molecule formed on the surface of the pixel electrodes 13, 13,. The main chain Rf-Si-X- group or Rf-Si- group in the single molecule unit is hardly stacked above the Rf-Si-X- group or Rf-Si- group that is the main chain in the unit. . For this reason, the thickness of the wettability variable layer 14 ′ is substantially equal to the Rf—Si—X— group or Rf—Si—, which is the main chain (here, corresponds to a side chain as a condensate) in a monomolecular unit. Equal to the base length. Further, this wettability variable layer 14 ′ is condensed such that the functional group Rf containing fluorine in the main chain in each single molecular unit is arranged on the surface side of the wettability variable layer 14 ′. The liquid repellency of the functional group Rf exhibits liquid repellency with respect to the organic compound-containing liquid.
[0051]
(5) Second cleaning step
Next, after leaving the transparent substrate 12 in the atmosphere, the surface 12a side of the transparent substrate 12 is rinsed with an m-xylene hexafloid solution (the same solution as the solvent of the silazane-based solution), so that the pixel electrodes 13, 13,. Unreacted silazane compound deposited on the surface of the protective insulating film 18 is washed away.
[0052]
(6) Exposure process
Next, as shown in FIG. 9, actinic rays are transmitted through the photomask substrate 40 with the photomask substrate 40 facing the surface 12a side of the transparent substrate 12, and the wettability variable layer 14 ′ is partially irradiated. To do. By the photomask substrate 40, the actinic rays are incident on the wettability variable layer 14 'in the region overlapping the pixel electrodes 13, 13,... And the region surrounding the arrangement range of the pixel electrodes 13, 13,. Thereby, the wettability variable layer 14 ′ becomes the pattern layer 14. At this time, actinic rays may be irradiated with the photomask substrate 40 in contact with the wettability variable layer 14 ′, or actinic rays are irradiated with the photomask substrate 40 separated from the wettability variable layer 14 ′. However, it is preferable that the photomask substrate 40 is brought into contact with the wettability variable layer 14 'as close as possible and lightly contacted. Active light includes visible light, ultraviolet light, infrared light, and the like, and is light in a wavelength region that excites a photocatalytic film 43 described later.
[0053]
Here, the photomask substrate 40 will be described with reference to FIGS. FIG. 21A is a plan view of the photomask substrate 40, and FIG. 21B is a cross-sectional view of the photomask substrate 40. The photomask substrate 40 has a transparent substrate 41 that transmits actinic rays. A mask 42 is formed on one surface 41 a of the transparent substrate 41 in a mesh pattern corresponding to the protective insulating film 18. That is, the mask 42 has a plurality of openings 42a, 42a,..., And the plurality of openings 42a, 42a,... Are arranged in a matrix so as to correspond to the surrounding areas 19, 19,. Thus, the mask 42 is formed in a mesh shape. The opening area of the opening 42 a surrounded by the mask 42 is slightly larger than the area of the surrounding region 19. Further, a mask 44 is formed in an annular shape on the outer peripheral portion of one surface 41 a of the photomask substrate 40. The mask 44 is formed so as to surround the mask 42 away from the outer edge of the mask 42, and an annular opening 45 is formed between the outer edge of the mask 42 and the mask 44. Then, a photocatalyst film 43 having a thickness of about 0.2 μm is formed on the entire one surface 41a of the transparent substrate 41 so as to cover the mask 42 and the mask 44, and the photocatalyst film 43 is formed in the openings 42a, 42a,. The opening 45 is closed.
[0054]
The mask 42 and the mask 44 reflect or absorb actinic rays and do not transmit actinic rays. The photocatalyst film 43 is formed by dispersing a photocatalyst in a transparent binder such as a resin, or is formed from the photocatalyst itself. The photocatalyst functions as a catalyst that promotes a chemical reaction by receiving actinic rays. As the photocatalyst, titanium oxide (TiO 2) is used.₂), Zinc oxide (ZnO), tin oxide (SnO)₂), Strontium titanate (SrTiO)_Three), Tungsten oxide (WO_Three), Bismuth oxide (Bi₂O_Three), Iron oxide (Fe₂O_Three). Here, titanium oxide is used as a photocatalyst. Titanium oxide includes anatase type and rutile type, and both can be used in the present invention, but anatase type titanium oxide is more preferable because the excitation wavelength is 380 nm or less.
[0055]
When the actinic ray is incident on the back surface 41b of the transparent substrate 41 using the photomask substrate 40 as described above, the openings 42a, 42a,... Are opposed to the surrounding regions 19, 19,. Further, all of the pixel electrodes 13, 13,... Are accommodated inside the opening 45. The active light is shielded by the mask 42 and the mask 44, but the active light is transmitted through the openings 42 a, 42 a,... Therefore, actinic rays do not enter the regions of the wettability variable layer 14 ′ that overlap the masks 42 and 44, but actinic rays enter the regions that overlap the openings 42 a, 42 a,.
[0056]
When active light passes through the photocatalytic film 43, active oxygen species (.OH) are generated. The active oxygen species transmitted through the photocatalyst film 43 reaches the wettability variable layer 14 ′ where the active light is incident, and the active light is blocked by the mask 42 in the region where the active light is not incident. Oxygen species do not reach. In this way, active oxygen species are generated by the incidence of active light on the photocatalyst film 43, and the generated active oxygen species diffuse in the gas phase between the photomask substrate 40 and the wettability variable layer 14 ′ and become wet. The chemical structure of the wettability variable layer 14 ′ is changed by the active oxygen species that has reached the property variable layer 14 ′. Since the opening area of the opening 42 a is slightly larger than the area of the surrounding region 19, the active oxygen species reaches slightly outside the surrounding region 19.
[0057]
In the wettability variable layer 14 ′, the region that does not overlap with the mask 42 and the mask 44 is substituted with a hydrophilic hydroxyl group for the Rf group exhibiting liquid repellency by the active oxygen species (.OH) generated by the action of the photocatalyst. As shown in the general formula (23).
[Chemical Formula 3]

These regions are the lyophilic regions 14a, 14a,... And the lyophilic region 14c. In the lyophilic regions 14a, 14a,... And the lyophilic region 14c, the functional group containing fluorine (above Rf) is decomposed / removed and substituted with a hydroxyl group.
[0058]
Further, in the lyophilic region 14a, the main chain of the condensate composed of silicon and oxygen is formed along the surface of the pixel electrodes 13, 13,. Is substituted with a hydroxyl group, so that the film thickness is also equal to the length of the HO—Si—X— group or the HO—Si— group which is the main chain in the single molecular unit (corresponding to a side chain as a condensate here). It can be very thin as 1 nm or less. Therefore, it is possible to inject charges such as holes from the pixel electrode 13 through the lyophilic region 14 a to the EL layer 15 by the voltage applied to the pixel electrode 13 and the counter electrode 16.
[0059]
On the other hand, in the wettability variable layer 14 ′, the region overlapping with the mask 42 and the mask 44 does not reach the active oxygen species, so that no chemical change occurs and still exhibits liquid repellency. This region is a liquid repellent region 14b and a liquid repellent region 14d. The lyophobic region 14b and the lyophobic region 14d are formed continuously with the lyophilic regions 14a, 14a,... And the lyophilic region 14c, and the lyophilic regions 14a, 14a,. It is thicker than the region 14c by the functional group Rf containing almost fluorine.
[0060]
(7) Third cleaning step
After the pattern layer 14 is formed by partially exposing the wettability variable layer 14 ′ as described above, the entire transparent substrate 12, particularly the surface of the pattern layer 14, is immediately rinsed with pure water. As a method of rinsing the surface of the pattern layer 14 with pure water, flowing pure water may be allowed to flow on the surface of the pattern layer 14, or the pattern layer 14 may be immersed in the pure water together with the transparent substrate 12. It may be. The time for rinsing the pattern layer 14 with pure water is not particularly limited, but it is desirable that the rinsing state be maintained for a predetermined time. After rinsing the surface of the pattern layer 14 with pure water, the pure water is evaporated to dry the surface of the pattern layer 14. The atmosphere to be dried may be air.
[0061]
(8) EL layer forming step
When the transparent substrate 12 is dried together with the surface of the pattern layer 14, the EL layer 15 is formed in each surrounding area 19. The EL layers 15, 15,... Are formed by applying a droplet discharge technique (inkjet technique). That is, as shown in FIG. 10, a head (nozzle) 70 capable of discharging an organic compound-containing liquid containing the constituent material of the EL layer 15 is opposed to the transparent substrate 12, and the drive device drives the transparent substrate 12. While the head 70 is relatively moved along the horizontal plane, the organic compound-containing liquid is discharged from the head 70 as the droplet 71 once or a plurality of times when the head 70 is positioned on the surrounding area 19. As a result, the droplet of the organic compound-containing liquid lands on the pattern layer 14 in the surrounding area 19. The landed droplet spreads in the lyophilic region 14a to form a film, and the film is solidified, whereby the EL layer 15 is formed. Further, an organic compound-containing liquid may be prepared for each of red, green, and blue colors, and the colors of the EL layers 15, 15,.
[0062]
Even when the organic compound-containing liquid is applied as described above, since the pattern layer 14 is the lyophilic region 14a in the surrounding region 19, the landed droplets are easily wetted and oozed, and the organic compound-containing liquid is It extends throughout the Go area 19. In addition, since the actinic ray is incident slightly outside the surrounding area 19 to form a lyophilic area 14 a wider than the surrounding area 19, the organic compound-containing liquid surely spreads in the entire surrounding area 19. Therefore, the EL layer 15 is formed with a uniform thickness, and no peeling occurs between the EL layer 15 and the pattern layer 14. Furthermore, since the periphery of each lyophilic region 14a is a liquid repellent region 14b, the organic compound-containing liquid does not bleed into the liquid repellent region 14b. Therefore, the organic compound-containing liquids of two adjacent pixels do not mix with each other. Therefore, the EL layers 15, 15,... Can always be formed with a uniform thickness, and color development with high color purity can be achieved when two adjacent pixels are organic compound-containing liquids having different emission colors.
[0063]
In addition, when the EL layer 15 has a laminated structure, an organic compound-containing liquid is prepared for each layer, and each organic compound-containing liquid is sequentially ejected into the surrounding area 19 with a nozzle to laminate each layer. I will do it. For example, in the case where the EL layer 15 has a two-layer structure including a hole injection layer and a light-emitting layer in a narrow sense, an organic compound-containing liquid for the hole injection layer (an organic compound constituting the hole injection layer (for example, a conductive high A hole injection layer is formed by discharging a dispersion liquid in which PEDOT), which is a molecule, and PSS), which is a dopant, are dispersed in an aqueous dispersion medium, into each surrounding region 19, and then the organic layer of the light-emitting layer in a narrow sense. The EL layer 15 is formed by discharging a compound-containing liquid (a solution in which a polyfluorene-based light-emitting material is dissolved in an organic solvent such as toluene, xylene, or tetralin) into each surrounding region 19. Even in this case, in the lyophilic region 14a of the pattern layer 14, the organic compound-containing liquid in the hole injection layer is familiar, and in the liquid repellent region 14b, the organic compound-containing liquid in the hole injection layer is repelled.
[0064]
(9) Counter electrode forming step
When the EL layers 15, 15,... Are formed by the droplet discharge method, the solvent / dispersion medium of the applied organic compound-containing liquid is dried. Next, the counter electrode 16 is formed so as to cover the EL layers 15, 15,... By a film forming method such as vapor deposition and sputtering, and the terminal 16 a of the counter electrode 16 is routed to the wiring 17. Connect (FIGS. 11 and 12). Here, the counter electrode 16 is deposited so that the entire counter electrode 16 is disposed inside the outer edge 14f of the lyophilic region 14c in plan view. Further, a terminal of a wiring for outputting a signal to the drain electrode 27 and the gate electrode 22 of the transistor 21 is exposed outside the liquid repellent region 14d so as to be connected to an external circuit. These terminal groups are formed by contact holes (not shown) formed in the protective insulating film 18 and the lyophilic region 14c or the protective insulating film 18, the lyophilic region 14c and the gate insulating film 23 outside the liquid repellent region 14d. It may be exposed. The terminal 16a of the counter electrode 16 is connected to one end 17a of the lead wiring 17 exposed through the contact hole 29 formed in the protective insulating film 18 and the liquid repellent region 14b (FIG. 12C). The other end 17b of the routing wiring 17 is exposed in the protective insulating film 18 and the liquid repellent region 14b outside the liquid repellent region 14d. Thus, since the counter electrode 16 does not block the liquid-repellent region 14d by the routing wiring 17, the liquid-repellent region 14d can be exposed in the shape of a continuous frame, and an external circuit can be exposed at the outer edge 14f of the liquid-repellent region 14d. It becomes possible to connect to the counter electrode 16. These contact hole groups for connection with an external circuit may be collectively formed as necessary. Even if the counter electrode 16 is formed, the EL layer 15 is formed so as to extend over the entire surrounding region 19, so that the counter electrode 16 does not directly contact the pixel electrode 13, and the counter electrode 16 and the pixel electrode 13 is not short-circuited.
[0065]
(10) Moisture blocking sheet bonding process
Next, as shown in FIGS. 13 and 14, a moisture barrier sheet 81 is prepared by laminating an adhesive layer 84 ′ composed of a resin before polymerization and crosslinking, a shielding layer 85, a nylon layer 86, and a protective resin layer 87 in this order. To do. Here, the area of the moisture blocking sheet 81 is equal to or larger than the area of the counter electrode 16, the shape of the outer edge of the moisture blocking sheet 81 is larger than the shape of the region surrounded by the inner edge 14e of the lyophilic region 14c, and the lyophilic solution The moisture shielding sheet 81 is prepared so as to be smaller than the shape of the region surrounded by the outer edge 14f of the sexual region 14c. The adhesive layer 84 ′ of the moisture blocking sheet 81 is bonded to the counter electrode 16 so as to cover the entire counter electrode 16 with the moisture blocking sheet 81. When adhering the moisture blocking sheet 81 to the counter electrode 16, the outer peripheral portion of the moisture blocking sheet 81 is overlaid on the inner peripheral portion of the lyophilic region 14 c and the outer peripheral portion of the lyophilic region 14 c is exposed from the moisture blocking sheet 81. Let When the adhesive layer 84 ′ is polymerized, cross-linked and cured, the adhesive layer 84 ′ is transformed into an adsorption layer 84 such as polyethylene or polypropylene (FIGS. 15 and 16). When water or oxygen is generated when the moisture blocking sheet 81 is bonded, the water and oxygen are removed by sufficiently drying. Although depending on the composition of the adhesive layer 84 ′, the moisture blocking sheet 81 is attached to the head 91 (shown in FIG. 14) having a larger area than the contact surface 81a of the moisture blocking sheet 81 when the moisture blocking sheet 81 is bonded. Accordingly, it is desirable to heat the moisture blocking sheet 81 and further press the moisture blocking sheet 81 against the transparent substrate 12 side. Since the entire surface of the moisture blocking sheet 81 can be pressure-bonded by such a head 91, the adhesive layer 84 'can be in close contact with the counter electrode 16 or the like without a gap.
[0066]
(11) Resin application process
Next, as shown in FIGS. 17 and 18, a liquid resin before curing such as a two-component epoxy resin, a thermosetting epoxy resin, or a photocurable resin is used on the outer periphery of the moisture shielding sheet 81 using a dispenser device or the like. Apply. Here, the resin is applied so that the resin spreads outward from the outer edge of the moisture blocking sheet 81 and extends. The liquid resin extending from the outer edge of the moisture blocking sheet 81 spreads and spreads over the entire exposed portion of the lyophilic region 14c. However, since the liquid repellent region 14d is patterned on the outer periphery of the lyophilic region 14c, the liquid resin does not bleed outside the outer edge 14f of the lyophilic region 14c. Thereby, liquid resin can be dammed up and it is not necessary to form the ring frame part conventionally. Further, since the outer periphery of the moisture blocking sheet 81 overlaps the inner periphery of the lyophilic region 14c and the thickness of the moisture blocking sheet 81 is 200 μm, the moisture blocking sheet 81 and the lyophilic region 14c are extremely thin. Since the resin flows up to the level difference, that is, the entrance corner 90 shown in FIG. 18, no bubbles remain in that portion. Therefore, the organic EL elements 11, 11,... Can be better sealed.
[0067]
Thereafter, when the applied resin is polymerized, crosslinked, and cured, the applied resin becomes the resin seal 82. If water or oxygen is generated when the resin seal 82 is generated, the water and oxygen are removed by sufficiently drying. The resin seal 82 formed in this manner can fill the gap between the moisture blocking sheet 81 and the member therebelow, thereby suppressing the intrusion of water and oxygen from the gap.
[0068]
(12) Gas barrier thin film deposition process
Next, a gas barrier thin film 83 is formed on the entire surface of the transparent substrate 12, that is, on the entire moisture blocking sheet 81 and the resin seal 82 by sputtering, PVD, or CVD (FIGS. 19 and 20). Here, when the thin film 83 is Al, the thin film 83 is formed by vapor deposition.₂O_ThreeIn this case, the film is formed by sputtering. When the gas barrier thin film 83 is formed by the sputtering method, wrinkles are generated on the surface of the resin seal 82, and the wrinkles become finer as the film thickness of the gas barrier thin film 83 increases. It is desirable to form the thin film 83 so that the film thickness is 3000 mm or less. Note that the gas barrier thin film 83 may be formed by blowing a carrier gas containing metal fine particles at about 200 ° C. onto the moisture blocking sheet 81 and the resin seal 82.
[0069]
By the way, if the gas barrier thin film 83 is formed without forming the resin seal 82, the gas barrier thin film 83 may be interrupted at the outer edge of the moisture blocking sheet 81 due to a step in the outer peripheral portion of the moisture blocking sheet 81. However, in this embodiment, since the resin seal 82 is formed so that the inclination angle α at the contact surface with the pattern layer 14 is less than 75 °, there is no steep portion due to the step of the moisture blocking sheet 81. Even a thin gas barrier thin film 83 with a thickness of about several thousand can be formed without interruption. Further, when the resin seal 82 is formed by curing a two-pack type epoxy resin or a thermosetting epoxy resin, the reduction rate of the resin seal 82 over time after the polymerization is generated is small. 83 does not cause wrinkles due to physical stress caused by the shrinkage of the resin seal 82.
[0070]
In the organic EL display panel 1 manufactured as described above, a current flows through the organic EL element 11 in accordance with a signal input by the pixel circuit via the signal line 51 and the scanning line 52. In the organic EL element 11, current flows when holes are injected from the pixel electrode 13 to the EL layer 15 and electrons are injected from the counter electrode 16 to the EL layer 15. Then, holes and electrons are transported in the EL layer 15, and the holes and electrons are recombined in the EL layer 15, whereby the EL layer 15 emits light. Since the pixel electrodes 13, 13,... And the transparent substrate 12 are transparent, the light emitted from the EL layer 15 is emitted from the back surface 12b of the transparent substrate 12, and the back surface 12b becomes the display surface.
[0071]
As described above, in the present embodiment, the wettability variable layer 14 ′ is formed by hydrolyzing and condensing the silazane compound, and the main chain as the condensate composed of silicon and oxygen is the pixel electrode 13, 13 and the protective insulating film 18 are formed on the entire surface along the surface of the protective insulating film 18, and the substantial thickness of the lyophilic region 14a in each surrounding region 19 is the same as that of the monomolecular unit of the wettability variable layer 14 ′. The thickness is very thin, excluding the functional group Rf containing fluorine from the main chain. Therefore, even if the pattern layer 14 is interposed between the pixel electrode 13 and the EL layer 15, the insulation of the pattern layer 14 can be ignored, and holes are injected from the pixel electrode 13 to the EL layer 15. Not disturbed.
[0072]
Further, in the present embodiment, the wettability variable layer 14 ′ is partially contained by irradiating the wettability variable layer 14 ′ with the active oxygen species through the photomask substrate 40 without containing the photocatalyst in the wettability variable layer 14 ′. To react. In the wettability variable layer 14 ′, the region irradiated with actinic rays becomes the lyophilic region 14a, and injection of holes from the pixel electrode 13 to the EL layer 15 is not hindered, and the pattern layer 14 is the EL layer. 15 is not chemically affected.
[0073]
In addition, the area irradiated with actinic rays in the wettability variable layer 14 ′ becomes the lyophilic area 14 a, and the organic compound-containing liquid easily gets wet in the lyophilic area 14 a, so that the EL layer 15 covers the entire surrounding area 19. It is easy to spread. As a result, the EL layer 15 is uniformly formed over the entire surrounding region 19, so that no short circuit occurs between the gate electrode 13 and the counter electrode 16. Further, since peeling does not easily occur between the EL layer 15 and the pattern layer 14, dark spots are unlikely to occur in the emitted EL layer 15.
[0074]
Further, the organic EL elements 11, 11,... Are sealed by adhering the moisture blocking sheet 81 to the counter electrode 16 and applying a resin to the outer periphery of the moisture blocking sheet 81. Here, the moisture blocking sheet 81 can sufficiently shield water and oxygen from the upper surface of the organic EL elements 11, 11,. Further, since the resin seal 82 is formed so as to extend from the outer peripheral edge of the moisture blocking sheet 81, even at the interface of the moisture blocking sheet 81, the outside can be prevented from entering water and oxygen by the resin seal 82. it can.
[0075]
In the EL layer forming step, the EL layers 15, 15,... Are patterned by controlling the bleeding of the organic compound-containing liquid using the wettability pattern of the pattern layer. Further, in the resin coating process, the wettable pattern of the pattern layer 14 is used to dam the resin of the resin seal 82. Thus, since the pattern layer 14 is used for both the patterning of the EL layer 15 and the resin damming, the manufacturing cost of the organic EL panel can be reduced. Further, since the resin of the resin seal 82 can be dammed without forming the ring frame portion as in the prior art, the cost for forming the ring frame portion can be reduced. Furthermore, since the lyophobic region 14d can be formed together with the patterning of the lyophilic region 14a for depositing the EL layer 15 in a predetermined region, productivity can be improved.
[0076]
In some cases, the gas barrier thin film 83 may have pinholes in the thickness direction. However, since the moisture barrier sheet 81 is provided on the counter electrode 16, pinholes are generated in the gas barrier thin film 83. Even so, since the moisture blocking sheet 81 adsorbs and blocks water and oxygen, it is possible to suppress water and oxygen from reaching the organic EL elements 11, 11,.
[0077]
The present invention is not limited to the above embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.
[0078]
For example, since the organic EL display panel 1 of the above embodiment is a self-luminous type, it can be used for a line scanning mechanism of an image forming apparatus such as a page printer.
In the above description, the counter electrode 16 serving as a cathode is common to all the organic EL elements 11, 11,..., But the cathode is patterned for each organic EL element 11 by using the pixel electrode 13 as a cathode. You may do it. The interface between the pixel electrode 13 and the EL layer 15 may include a low work function material having excellent electron injection properties, and the lower layer may include a material having a low electrical resistivity in order to reduce the sheet resistance of the pixel electrode 13. . At this time, the counter electrode 16 becomes an anode, and the EL layers 15, 15,... Are appropriately layered with electron transport at the interface with the pixel electrode 13, and the layer with hole transport is at the interface with the counter electrode 15. preferable. The display surface of the organic EL display panel 1 may be on the transparent substrate 12 side, or the moisture barrier sheet 81 and the gas barrier thin film 83 may be transparent and may be on the gas barrier thin film 83 side. Further, instead of the plate-like transparent substrate 12, a sheet-like transparent film substrate may be used.
[0079]
In the above description, the plurality of EL layers 15, 15,... Are patterned by the droplet discharge method. However, since the lyophilic regions 14a, 14a,... Are patterned in a matrix in the pattern layer 14, the organic substrate-containing liquid is applied to the pattern layer 14 and the transparent substrate 12 is rotated (spin coating method). The plurality of EL layers 15, 15,... Can be patterned in a matrix. Further, by utilizing the lyophilic and lyophobic patterning of the pattern layer 14, the plurality of EL layers 15, 15,... May be patterned in a matrix by a dip coating method or a die coating method. Further, the plurality of EL layers 15, 15,... May be patterned in a matrix using a planographic printing method, an intaglio printing method, a relief printing method, or other printing methods.
[0080]
In the above description, the wettability variable layer 14 ′ is formed by the dip coating method, but the wettability variable layer 14 ′ may be formed by a spin coating method or a brush coating method.
[0081]
In the above description, the wettability variable layer 14 ′ does not contain a photocatalyst, but the wettability variable layer 14 ′ may contain a photocatalyst by applying a silazane-based solution containing a photocatalyst. In this case, the photocatalyst film 43 may not be provided on the photomask substrate 40.
[0082]
Moreover, although the silazane compound was mentioned as a silane compound which has a functional group containing a fluorine, other silane compounds, such as a silane coupling agent (fluoroalkyl group containing silicon compound which can be hydrolytically condensed), and other liquid repellency are shown. It may be a functional group, and the substituted functional group may be a lyophilic functional group other than a hydroxyl group.
[0083]
In the above description, the moisture blocking sheet 81 has a four-layer structure including the adsorption layer 84, the shielding layer 85, the nylon layer 86, and the protective resin layer 87. However, the moisture shielding sheet 81 is in order of the adsorption layer 84 and the shielding layer. 85, a three-layer structure including a protective resin layer 87 may be used.
[0084]
Alternatively, after the protective insulating film forming step and before the first cleaning step, the mesh-like partition wall 20 may be patterned so as to overlap the protective insulating film 18 as shown in FIG. The width of the partition wall 20 increases as it approaches the transparent substrate 12 and is narrower than the width of the protective insulating film 18. The partition wall 20 has insulating properties and is formed of a resin such as a polyimide resin, a novolac resin, or an acrylic resin.
[0085]
In the above description, the resin is applied to the outer peripheral portion of the moisture blocking sheet 81 in the resin coating step. However, the resin may be applied so as to cover the entire moisture blocking sheet 81. Even in this case, the resin is applied so as to extend from the outer peripheral edge of the moisture blocking sheet 81, and the resin is also poured onto the lyophilic region 14c as shown in FIG. Even in this case, the resin is blocked by the liquid repellent region 14d.
[0086]
In the above description, the gas barrier thin film 83 is entirely covered with the gas barrier thin film 83 in the gas barrier thin film forming step. However, as shown in FIG. 24, the gas barrier thin film 83 is formed so that the central portion of the moisture barrier sheet 81 is exposed. A film may be formed. In this case, the gas barrier thin film 83 is formed in an annular shape, and the resin seal 82 is covered with the gas barrier thin film 83.
[0087]
Further, in the above description, the moisture blocking sheet 81 is adhered to the counter electrode 16 from the viewpoint of sealing properties, but the process may be omitted. However, as shown in FIG. 25, in the resin application process, the resin is poured so as to cover the entire counter electrode 16, and the resin is poured so that the resin also overlaps the lyophilic region 14c. Thereafter, a gas barrier thin film 83 is formed so as to cover the entire resin seal 82.
[0088]
【The invention's effect】
According to the display panel of the present invention, since the flow of the sealing resin is easily restricted by the liquid repellency that the pattern layer develops, the sealing resin can be formed in a predetermined region.
According to the display panel manufacturing method of the present invention, the flow of the resin coated in the resin coating process is limited by the pattern layer forming process without forming a frame as a wall having a three-dimensional height. be able to. In particular, wettability can be easily improved by irradiating the third region of the wettability variable layer with actinic rays. And since the first region is not irradiated with actinic rays, the wettability is low. Therefore, when the resin is applied so as to overlap the third region, the resin applied to the third region is a region with low wettability in the first region. Can be dammed.
Moreover, the wettability of each 2nd area | region improves by providing so that 2nd area | regions may be spaced apart and irradiating each 2nd area | region with an actinic ray. Then, when the organic compound-containing liquid is applied to each second region, the organic compound-containing liquid is easily adapted to the second region. Can do. Further, the applied organic compound-containing liquid oozes out in the second area and repels around each second area, so that the organic compound-containing liquid is not mixed in the adjacent first electrode, that is, the adjacent first electrode. Moreover, since the organic compound-containing liquid oozes on the first electrode, the thickness of the EL layer becomes uniform.
As described above, the wettability variable layer is formed, and the wettability pattern is formed by partially irradiating the wettability variable layer, and the EL layer patterning is performed using the wettability pattern of the wettability variable layer. Further, the resin is dammed up using the wettability pattern of the wettability variable layer. Since the wettability pattern of the wettability variable layer is used as described above, it is not necessary to form a ring frame portion as in the prior art. The wettability variable layer is also used for EL layer patterning and resin damming. Therefore, the manufacturing cost of the organic EL panel can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an organic EL display panel manufactured by a manufacturing method to which the present invention is applied.
FIG. 2 is a plan view showing the organic EL display panel.
FIG. 3 is an enlarged view of a cross section of the organic EL display panel.
FIG. 4 is a plan view showing a pattern layer formed on the organic EL display panel.
FIG. 5 is an enlarged view of a region 5 in FIG. 1;
FIG. 6 is a drawing showing a step for manufacturing the organic EL display panel.
FIG. 7 is a drawing showing a continuation step of FIG. 6;
FIG. 8 is a drawing showing a continuation step of FIG. 7;
FIG. 9 is a drawing showing a continuation step of FIG. 8;
FIG. 10 is a drawing showing a continuation step of FIG. 9;
FIG. 11 is a drawing showing a continuation step of FIG. 10;
12 (a) is a drawing showing a cross section taken along line AA in FIG. 11, and FIG. 12 (b) is a drawing showing a cross section taken along line BB in FIG. (C) is the drawing which showed the CC line section in FIG.
FIG. 13 is a drawing showing a continuation step of FIG. 11;
14 (a) is a drawing showing a cross section taken along line AA in FIG. 13, and FIG. 14 (b) is a drawing showing a cross section taken along line BB in FIG. FIG. 14C is a cross-sectional view taken along the line CC in FIG.
FIG. 15 is a drawing showing a continuation step of FIG. 13;
16 (a) is a drawing showing a cross section taken along line AA in FIG. 15, and FIG. 16 (b) is a drawing showing a cross section taken along line BB in FIG. (C) is a cross-sectional view taken along the line CC in FIG.
FIG. 17 is a drawing showing a continuation step of FIG. 15;
18 (a) is a drawing showing a cross section taken along line AA in FIG. 17, and FIG. 18 (b) is a drawing showing a cross section taken along line BB in FIG. FIG. 18C is a cross-sectional view taken along the line CC in FIG.
FIG. 19 is a drawing showing a continuation step of FIG. 17;
20 (a) is a drawing showing a cross section taken along line AA in FIG. 19, and FIG. 20 (b) is a drawing showing a cross section taken along line BB in FIG. FIG. 20C is a cross-sectional view taken along line CC in FIG.
FIG. 21 is a view showing a photomask substrate used in manufacturing the organic EL display panel, wherein (a) is a plan view and (b) is a cross-sectional view.
FIG. 22 is a cross-sectional view showing an organic EL display panel different from FIG.
FIG. 23 is a cross-sectional view showing an organic EL display panel different from those shown in FIGS.
24 is a cross-sectional view showing an organic EL display panel different from those shown in FIGS. 1, 22, and 23. FIG.
25 is a cross-sectional view showing an organic EL display panel different from those shown in FIGS. 1, 22, 23, and 24. FIG.
FIG. 26 is a sectional view showing a sealing structure of a conventional organic EL display panel.
[Explanation of symbols]
1 ... Organic EL display panel
11 ... Organic EL element
12 ... Transparent substrate
13: Pixel electrode
14 ... Pattern layer
14 '... wettability variable layer
14a: first lyophilic region
14b: first liquid repellent region
14c second lyophilic region
14d: second liquid repellent region
15 ... EL layer
16 ... Counter electrode
81 ... Moisture barrier sheet
82… Resin seal
83… Gas barrier thin film
84… Adsorption layer
85 ... Shielding layer

Claims (6)

A substrate,
A display element having a plurality of pixels arranged on the substrate;
A pattern layer in which a region on the substrate around the display element exhibits liquid repellency;
A sealing resin in which the shape of the outer edge is blocked by the liquid-repellent region of the pattern layer;
With
The display element is covered with a moisture blocking sheet, and the moisture blocking sheet is covered with the sealing resin on the outer periphery thereof,
The display panel, wherein the moisture blocking sheet and the sealing resin are covered with a gas barrier thin film.   The display panel according to claim 1, wherein the moisture blocking sheet is formed on an inner periphery of the sealing resin.   The display panel according to claim 1, wherein a pixel of the display element is an organic EL element.   The display element includes an electrode, the electrode is connected to a wiring provided below a pattern layer in the liquid repellency region, and the wiring is exposed outside the liquid repellency region. The display panel according to any one of claims 1 to 3, wherein:   The display element has a pair of electrodes, and at least a part of one of the pair of electrodes is covered with an lyophilic region for electrodes of the pattern layer. 5. The display panel according to any one of 4.   6. The display panel according to claim 1, wherein at least a part of the sealing resin is formed on a lyophilic region for the sealing resin of the pattern layer.

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