JP2004311111A - Method for manufacturing organic electroluminescent element and organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing at low cost an organic electroluminescent element excellent in uniformity in the layer thickness of an organic thin layer, light emitting efficiency, light amount uniformity, and durability, while allowing a patterned organic layer to be easily formed on a substrate, and to provide the electroluminescent element. <P>SOLUTION: While a version having at least one organic layer on a pattern and a first substrate are overlapped so that the organic layer side of the version and at least the electrode side of the first substrate having an electrode are opposed each other, at least either a heating process or a pressing process is performed. Then the version is peeled off to transfer the organic layer on the electrode side of the first substrate. Using the process or repeating the process, a single organic layer or laminated organic layers are formed on the first substrate. A second substrate is combined over the top surface of the organic layer to manufacture the organic electroluminescent element. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

注：（１） ＴＭＡ法により測定した（昇温速度：１０℃／ｍｉｎ）。
【０１１７】
（Ｃ） 転写材料の作製
上記（Ａ）で作製した各版上に、真空蒸着法によりトリス（２−フェニルピリジル）イリジウム錯体［燐光発光材（オルトメタル錯体）］、及び４，４’−Ｎ，Ｎ’−ジカルバゾールビフェニル（ホスト材）をそれぞれ０．１ ｎｍ／秒、１ ｎｍ／秒の速度で共蒸着し、４０ ｎｍの厚さの発光性有機層を形成し、転写材料を作製した。
【０１１８】
（Ｄ） 積層体Ｄ（基板／陰極）の作製
表１に示す各基板のうちＮｏ．１０１，１０４及び１０８を洗浄容器に入れ、イソプロピルアルコール（ＩＰＡ）により洗浄した後、発光面積が５ ｍｍ×５ ｍｍになるようにマスクを設置し、蒸着法により２５０ ｎｍの膜厚でＡｌを成膜することにより陰極を形成した。陰極よりアルミニウムのリード線を結線し、積層体Ｎｏ．Ｄ１０１，Ｄ１０４及びＤ１０８を得た。
【０１１９】
（Ｅ） 積層体Ｅ（基板／陰極／有機層）の作製
上記（Ｄ）と同様にして、表１に示す各基板のうちＮｏ．１０３，１０４，１０５，１０６，１０８及び１０９に、蒸着法により２５０ｎｍの膜厚でＡｌを成膜することにより陰極を形成し、陰極付き基板を作製した。次いで陰極上に、下記構造式（１）：
【化１】

により示される構造を有する電子輸送性有機材料に対しＬｉＦが１０重量％となるように各々の材料の蒸着速度を調整し、３６ ｎｍの膜厚で混合層を積層し、電子輸送性有機層を作製した。更にＡｌ陰極よりアルミニウムのリード線を結線し、積層体Ｎｏ．Ｅ１０３，Ｅ１０４，Ｅ１０５，Ｅ１０６，Ｅ１０８及びＥ１０９を作製した。
【０１２０】
（Ｆ） 積層体Ｆ（基板／陽極）の作製
表１に示す各基板のうちＮｏ．１０１，１０２，１０６，１０８及び１０９を、真空チャンバー内に導入し、ＳｎＯ_２含有率が１０質量％のＩＴＯターゲット［インジウム：錫＝９５：５（モル比）］を用いて、ＤＣマグネトロンスパッタリング（基板の温度：２５０℃、酸素圧：１×１０^−３ Ｐａ）により、厚さ０．２μｍのＩＴＯ薄膜からなる透明電極を形成した。ＩＴＯ薄膜の表面抵抗を測定したところ１０Ω／□であった。透明電極（ＩＴＯ）より、アルミニウムのリード線を結線し、積層体を形成した。透明電極を形成した各基板を洗浄容器に入れ、イソプロピルアルコール（ＩＰＡ）により洗浄した後、酸素プラズマ処理を行うことにより、積層体Ｎｏ．Ｆ１０１，Ｆ１０２，Ｆ１０６，Ｆ１０８及びＦ１０９を作製した。
【０１２１】
（Ｇ） 積層体Ｇ（基板／陽極／有機層）の作製
上記（Ｆ）と同様にして、表１に示す各基板のうちＮｏ．１０１，１０２，１０６，１０７及び１０９に、厚さ０．２μｍのＩＴＯ薄膜からなる透明電極を形成し、透明電極（ＩＴＯ）よりアルミニウムのリード線を結線し、積層体を作製した。透明電極を形成した各基板を洗浄容器に入れ、イソプロピルアルコール（ＩＰＡ）により洗浄した後、酸素プラズマ処理を行った。処理した透明電極の表面に、ポリエチレンジオキシチオフェン・ポリスチレンスルホン酸の水性分散液（ＢＡＹＥＲ社製、商品名：Ｂａｙｔｒｏｎ Ｐ、固形分１．３質量％）をスピンコートした後、１５０℃で２時間真空乾燥し、厚さ１００ ｎｍのホール輸送性有機層を形成することにより、積層体Ｎｏ．Ｇ１０１，Ｇ１０２，Ｇ１０６，Ｇ１０７及びＧ１０９を作製した。
【０１２２】
（Ｈ） 剥離転写法による有機層の形成
上記（Ｄ）で作製した積層体Ｎｏ．Ｄ１０１，Ｄ１０４及びＤ１０８と、上記（Ｅ）で作製した積層体Ｎｏ．Ｅ１０３，Ｅ１０５，Ｅ１０８及びＥ１０９と、上記（Ｆ）で作製した積層体Ｎｏ．Ｆ１０２及びＦ１０６と、上記（Ｇ）で作製した積層体Ｎｏ．Ｇ１０２，Ｇ１０７及びＧ１０９とに、上記（Ｃ）で作製した転写材料の発光性有機層を転写した。上記各積層体の被成膜面（陰極、陽極、電子輸送性有機薄膜又はホール輸送性有機薄膜を有する面）に、転写材料の発光性有機層側が対面するように両者を重ね、０．５ ＭＰａの加圧力の１対の熱板（両熱板ともに温度が１１０℃に調整された熱プレス機）の間に設置し、３０秒間の加熱処理及び加圧処理を同時に行った。ついで版を引き剥がし、各積層体の被成膜面上に発光性有機層を形成することにより、積層体Ｈ（Ｎｏ．ＨＤ１０１，ＨＤ１０４，ＨＤ１０８，ＨＥ１０３，ＨＥ１０５，ＨＥ１０８，ＨＥ１０９，ＨＦ１０２，ＨＦ１０６，ＨＧ１０１，ＨＧ１０２，ＨＧ１０７及びＨＧ１０９）を作製した。
【０１２３】
（Ｉ） 素子の作製
上記（Ｈ）で作製した積層体ＨのうちＮｏ．ＨＤ１０１，ＨＤ１０４，ＨＤ１０８，ＨＥ１０３，ＨＥ１０５，ＨＥ１０８，ＨＥ１０９，ＨＦ１０２，ＨＦ１０６，ＨＧ１０２，ＨＧ１０７及びＨＧ１０９を第１基板（第一の基板）側積層体として使用し、上記（Ｄ）で作製した積層体Ｎｏ．Ｄ１０８と、上記（Ｅ）で作製した積層体Ｎｏ．Ｅ１０３，Ｅ１０４，Ｅ１０６及びＥ１０８と、上記（Ｆ）で作製した積層体Ｎｏ．Ｆ１０１，Ｆ１０２，Ｆ１０８及びＦ１０９と、上記（Ｇ）で作製した積層体Ｎｏ．Ｇ１０１，Ｇ１０２，Ｇ１０６及びＧ１０９と、上記（Ｈ）で作製した積層体Ｎｏ．ＨＧ１０１とを第２基板（第二の基板）側積層体として使用し、各第１基板側積層体と各第２基板側積層体とを表４に示す組合わせで貼り合わすことにより、有機ＥＬ素子を作製した。両者の貼り合わせは、第１基板側積層体の発光性有機層側と、第２基板側積層体の被成膜面（陰極、陽極、電子輸送性有機薄膜、ホール輸送性有機薄膜又は発光性有機層を有する面）とが対面するように両者を重ね、０．３ ＭＰａの加圧力の一対のローラー（両方ともに温度を１６０℃に調整した加熱ローラー）の間を０．１ ｍ／分の速度で通すことにより行った。表４に示す各第１基板側積層体と各第２基板側積層体との組合せは、得られる有機ＥＬ素子が陰極及び陽極を有し、かつ少なくともその片面から発光を取り出すことができる構成となるようにした。
【０１２４】
（Ｊ） 評価
上記（Ｉ）で作製した有機ＥＬ素子の発光性について評価を行った。ケースレーインスツルメンツ（株）製ソースメジャーユニット２４００型を用いて、直流電圧を有機ＥＬ素子に印加したところ、いずれの有機ＥＬ素子も２ ｍＡの駆動電流で充分な発光が検出され、貼り合せは良好であった。
【０１２５】
上記（Ｈ）で作製した積層体Ｈについて、画素位置精度を評価した。画素位置精度の評価方法について説明する。まず各積層体Ｈ（Ｎｏ．ＨＤ１０１，ＨＤ１０４，ＨＤ１０８，ＨＥ１０３，ＨＥ１０５，ＨＥ１０８，ＨＥ１０９，ＨＦ１０２，ＨＦ１０６，ＨＧ１０１，ＨＧ１０２，ＨＧ１０７及びＨＧ１０９）を５個ずつ作製し、各積層体Ｈの発光性有機層が設けられた面について、５０００μｍ×５０００μｍの正方形状領域の顕微鏡写真を撮影した。この時、正方形状領域の左下頂点をＸＹ座標の原点とみなし、正方形状領域の左側縦辺がＹ軸に一致しているとみなした。そして基準とする一つの画素（以下「基準画素」という）の左下頂点がＸＹ座標の原点と一致し、かつ基準画素の左側縦辺がＹ軸に一致するように、位置を合わせて撮影した。発光性有機層が理想的に転写されていれば、配列している各画素の縦辺長さは５０μｍであり、画素間隔は２５μｍであるので、正方形状領域の左上頂点［座標（０，５０００μｍ）の点］と、原点からＹ軸方向に沿って６７個目の画素の左上頂点（以下「測定点」という）が一致するはずである。そこで、正方形状領域の左上頂点［座標（０，５０００μｍ）の点］を理想点とし、各顕微鏡写真の測定点に関して理想点からのズレを調べた。測定点の理想点からのズレは、ＸＹ座標の原点と理想点間の長さ（５０００μｍ）、すなわち正方形状領域の一辺の長さを基準長さとし、原点と測定点間の長さを測定し、その値と基準長さとの差を求めたものである。Ｎｏ．１〜１７の各有機ＥＬ素子のそれぞれについて５点の測定結果を平均した。画素位置精度の評価基準は下記の通りである。結果を表４に示す。
◎：理想点からのズレが０．１％未満（５μｍ未満）であった。
○：理想点からのズレが０．５％未満（２５μｍ未満）であった。
×：理想点からのズレが０．５％以上（２５μｍ以上）であった。
【０１２６】
理想点からのズレが０．５％以上になると、有機ＥＬ素子を駆動回路と合わせる際に、駆動回路と画素の位置が合わせられないという問題が生じる。また複数の発光性有機層を色分け（例えば３色）を伴って設ける場合に、画素が重なるという問題が生じる。
【０１２７】
比較例１
白板ガラス（０．５ ｍｍ×２．５ ｃｍ×２．５ ｃｍ）を、真空チャンバー内に導入し、ＳｎＯ_２含有率が１０質量％のＩＴＯターゲット［インジウム：錫＝９５：５（モル比）］を用いて、ＤＣマグネトロンスパッタリング（基板の温度：２５０℃、酸素圧：１×１０^−３ Ｐａ）により、厚さ０．２μｍのＩＴＯ薄膜からなる透明電極を形成した。ＩＴＯ薄膜の表面抵抗を測定したところ１０Ω／□であった。透明電極（ＩＴＯ）より、アルミニウムのリード線を結線した後、透明電極を形成した白板ガラス板を洗浄容器に入れ、イソプロピルアルコール（ＩＰＡ）により洗浄した後、酸素プラズマ処理を行った。酸素プラズマ処理を施した透明電極の表面に、ポリエチレンジオキシチオフェン・ポリスチレンスルホン酸の水性分散液（ＢＡＹＥＲ社製、商品名：Ｂａｙｔｒｏｎ Ｐ、固形分１．３質量％）をスピンコートした後、１５０℃で２時間真空乾燥し、厚さ１００ ｎｍのホール輸送性有機層を形成した。次いで、ホール輸送性有機層上に、表２に示す組成の発光性有機層用塗布液を、グラビア印刷機を用いて１０ ｍ／ｍｉｎの速度で塗布し、８０℃で乾燥することにより、４０ ｎｍ（厚さ）×１００μｍ×５０μｍの凸状の画素部を２５μｍの間隔で設けた画素パターンからなる発光性有機層を形成した。
【０１２８】
【表２】

【０１２９】
さらに発光性有機層上に、ポリビニルブチラール（Ｍｗ＝５００００、アルドリッチ社製）、下記構造式（２）：
【化２】

により表される電子輸送性化合物、及び１−ブタノールを含む電子輸送性有機層用塗布液を、エクストルージョン塗布機を用いて１０ ｍ／ｍｉｎの速度で塗布し、８０℃で乾燥することにより、厚さ３６ ｎｍの電子輸送性有機層を形成した。上記電子輸送性有機層塗布液の組成を表３に示す。
【０１３０】
【表３】

【０１３１】
最後に、蒸着法により２５０ ｎｍの膜厚でＡｌを成膜した（陰極）。更にＡｌ陰極よりアルミニウムのリード線を結線し、有機ＥＬ素子を作製した。得られた有機ＥＬ素子について、実施例１〜１６と同様にして、画素位置精度について評価を行った。結果を表４に示す。
【０１３２】
【表４】

注：（１） ＷＧは白板ガラスを表し、ＳＧは石英ガラスを表し、ＰＩはポリイミドシートを表し、Ａｌはアルミ箔を表し、ＵＶは紫外線硬化樹脂層を表し、ＰＶＣは硬質ポリ塩化ビニルシートを表し、ＴＨは熱硬化樹脂層を表し、ＰＥＴはポリエチレンテレフタレートシートを表し、ＰＥＳはポリエーテルスルホンシートを表し、ＩＮは陰極を表し、Ｙは陽極を表し、ＥＬは発光性有機層を表し、ＴＬは発光性有機層以外の有機層を表し、／／は貼り合せ位置を表す。
（２） 画素が滲んでいたため、おおよその境界面から求めた。
【０１３３】
表４から明らかなように、実施例１〜１６では画素位置精度に優れる有機電界発光素子が簡易に得られることが分かった。これに対して比較例１では、転写を行なわないので画素位置精度が劣っていた。また実施例１〜１６は両方の電極側から作製しているので、片側から積層している比較例１と比較すると、生産性よく作製できた。
【０１３４】
実施例 １７ 〜 ３２（版上への有機層の形成が塗布成膜による例）
転写材料を下記のように変更した以外は、実施例１〜１６と同様にして有機ＥＬ素子（Ｎｏ．１８〜３３）を作製した。転写材料は、実施例１〜１６と同様にして作製した凸版上に、表５に示す組成の発光性有機層用塗布液をバーコータにより塗布し、室温で乾燥させることにより、４０ ｎｍの厚さの発光性有機層を形成することにより作製した。この転写材料を用いて作製した積層体を積層体Ｈ’とした。
【０１３５】
【表５】

【０１３６】
得られた有機ＥＬ素子（Ｎｏ．１８〜３３）について、実施例１〜１６と同様にして、発光性について評価を行った。その結果いずれの有機ＥＬ素子も２ ｍＡの駆動電流で充分な発光が検出され、貼り合せは良好であった。
【０１３７】
また積層体Ｈ’について、実施例１〜１６と同様にして、画素位置精度を評価した結果を表６に示す。
【０１３８】
【表６】

注：（１） 表４と同じ
【０１３９】
表６から明らかなように、実施例１７〜３２では画素位置精度に優れる有機電界発光素子が簡易に得られることが分かった。
【０１４０】
実施例 ３３ 〜 ４２
積層体Ｇを、下記のように変更した以外は、実施例１〜１６と同様に有機ＥＬ素子（Ｎｏ．３４〜４３）を作製した。積層体Ｇは、実施例１〜１６と同様にして、表１に示す各基板のうちＮｏ．１０１，１０２，１０６，１０７及び１０９に、厚さ０．２μｍのＩＴＯ薄膜からなる透明電極を形成し、透明電極（ＩＴＯ）よりアルミニウムのリード線を結線することにより作製した。透明電極を形成した各基板を洗浄容器に入れ、イソプロピルアルコール（ＩＰＡ）により洗浄した後、酸素プラズマ処理を行った。処理した透明電極の表面に、下記構造式（３）：
【化３】

により表される高分子化合物（Ｅｔ−ＰＴＰＤＥＫ）、下記構造式（４）：
【化４】

により表される添加剤（ＴＢＰＡ）、及びジクロロエタンを含むホール輸送性有機層用塗布液を、エクストルージョン型塗布機を用いて塗布し、室温で乾燥させることにより、厚さ４０ ｎｍのホール輸送性有機層を形成した。ホール輸送性有機層用塗布液の組成比を表７に示す。得られた積層体を積層体Ｇ’とした。積層体Ｇ’に発光性有機層を転写した積層体を積層体ＨＧ’とした。
【０１４１】
【表７】

【０１４２】
得られた有機ＥＬ素子（Ｎｏ． ３４〜４３）について、実施例１〜１６と同様にして、発光性について評価を行った。その結果いずれの有機ＥＬ素子も２ ｍＡの駆動電流で充分な発光が検出され、貼り合せは良好であった。
【０１４３】
また積層体ＨＧ’について、実施例１〜１６と同様にして、画素位置精度を評価した結果を表８に示す。
【０１４４】
【表８】

注：（１） 表４と同じ
【０１４５】
表８から明らかなように、実施例３３〜４２では画素位置精度に優れる有機電界発光素子が簡易に得られることが分かった。
【０１４６】
実施例 ４３ 〜 ５８
転写材料を下記のように変更した以外は、実施例１〜１６と同様に有機ＥＬ素子（Ｎｏ．４４〜５９）を作製した。転写材料は、２ ｃｍ（厚さ）×５ ｃｍ×５ ｃｍのステンレス板［熱線膨張係数：１２ ｐｐｍ／℃（ＴＭＡ測定、１０℃／ｍｉｎ）］の中央部の正方形状領域（一辺の長さ：２０ ｍｍ）に、フォトリソグラフィー法（ステンレス板のパターン部を形成する部分にマスクをし、エッチングにより非パターン部を除去することにより凸部を形成した）により５μｍ（高さ）×１００μｍ×５０μｍの凸部を２５μｍの間隔で設けたパターン部を有する版を作製し、その上に実施例１〜１６と同様にして発光性有機層を形成することにより作製した。この転写材料を用いて作製した積層体を積層体Ｈ’’とした。
【０１４７】
得られた有機ＥＬ素子（Ｎｏ．４４〜５９）について、実施例１〜１６と同様にして、発光性について評価を行った。その結果いずれの有機ＥＬ素子も、２ ｍＡの駆動電流で充分な発光が検出され、貼り合せは良好であった。
【０１４８】
また積層体Ｈ’’について、実施例１〜１６と同様にして、画素位置精度を評価した結果を表９に示す。
【０１４９】
【表９】

注：（１） 表４と同じ
【０１５０】
表９から明らかなように、実施例４３〜５８では画素位置精度に優れる有機電界発光素子が簡易に得られることが分かった。
【０１５１】
【発明の効果】
以上詳述したように、所定のパターン部を有する版上に有機層を設け、その有機層を基板に転写することにより、基板上にパターン状の有機層を簡便に形成できるとともに、有機層の膜厚均一性、発光効率、発光量の均一性及び耐久性に優れた有機電界発光素子を低コストで製造する方法を提供することができる。
【０１５２】
版は機械的強度及び安定性に優れるため、有機層を転写した際の位置精度が良い。版を使用することにより、高精細かつ高精度のパターン（画素等）を容易に、かつ高い生産性で製造できる。さらに有機層の転写後に版を洗浄／乾燥することにより、繰り返し使用することができる。また版を使用する場合は、少なくともパターン部に有機層を形成すればよい。このため版を使用する有機電界発光素子の製造には、廃棄物が少ない、コストが低い、特殊な製造設備が要らない等の利点がある。
【０１５３】
本発明の製造方法により得られる有機電界発光素子は、フルカラーディスプレイ、液晶表示素子のバックライト、照明用の面光源、プリンターの光源アレイ等に好適である。
【図面の簡単な説明】
【図１】パターン部に有機層を設けた凸版の一例を示す（概略）断面図である。
【図２】図１の凸版の平面図である。
【図３】パターン部及び非パターン部に有機層を設けた凸版の一例を示す（概略）断面図である。
【図４】パターン部に有機層を設けた凹版の一例を示す（概略）断面図である。
【図５】図４の凹版の平面図である。
【図６】パターン部及び非パターン部に有機層が設けられた凹版の一例を示す（概略）断面図である。
【図７】有機層を設けた平版の一例を示す（概略）断面図である。
【図８】図７の凹版の平面図である。
【図９】有機層用塗布液が塗布された平版の一例を示す（概略）断面図である。
【符号の説明】
１・・・版
１１・・・凸部
１２・・・凹部
２・・・パターン部
３・・・非パターン部
４・・・有機層
４’・・・有機層用塗布液[0001]
BACKGROUND OF THE INVENTION
The present invention uses a transfer material in which an organic layer is provided on a plate having a predetermined pattern portion, and is suitable for organic electroluminescence suitable for full-color displays, backlights for liquid crystal display elements, surface light sources for illumination, light source arrays for printers, etc. The present invention relates to a method for manufacturing an element, and an organic electroluminescent element obtained by the manufacturing method.
[0002]
[Prior art]
Organic light emitting devices such as organic electroluminescent devices (organic EL devices) are attracting attention as new optical devices because they can be easily applied to planar light emitting devices. Specifically, a solid light-emitting type inexpensive large-area full-color display element and a use as a writing light source array are considered promising, and many developments have been made. In general, an organic light emitting device is composed of a light emitting layer and a pair of counter electrodes (a back electrode and a transparent electrode) sandwiching the light emitting layer. When an electric field is applied between a pair of counter electrodes of the organic light emitting device, electrons are injected from one electrode into the light emitting layer, and holes are injected from the other electrode. When electrons and holes recombine in the light emitting layer and the energy level returns from the conduction band to the valence band, the energy is released as light and emits light.
[0003]
Many of the organic thin film formation of an organic EL element is manufactured by a vapor deposition method. When the organic layer is formed with a predetermined pattern, a mask having openings with a predetermined pattern is used. In the case of forming a fine pattern, if the mask is thick, it disturbs a dissipating path, so that a uniform film cannot be formed. For this reason, the mask is designed to be thin by using a durable metal, glass, ceramic, heat resistant resin, or the like as a material.
However, if it is repeatedly used, distortion occurs and the position of the predetermined pattern is shifted, so that productivity is lacking.
[0004]
Japanese Patent Laid-Open Nos. 9-167684 and 2000-195665 propose a method in which an organic layer is uniformly formed on a mica or film temporary substrate in advance by vapor deposition, and then the substrate and the organic layer are brought close to each other and then heat-deposited. doing. However, in these methods, a uniform organic layer can be formed by the first vapor deposition, but there is a problem that it is difficult to make the organic layers uniformly approach by the next vapor deposition, and the production efficiency is poor.
[0005]
In recent years, polymer light-emitting thin films, which are advantageous for large-area applications and are expected to be used for flexible displays, and polymer-type devices using light-emitting thin films in which low-molecular compounds are dispersed in a binder resin have attracted attention. ing. Polymeric light-emitting thin films include polyparaphenylene vinylene ("Nature"), 347, 539 (1990), and poly-3-alkylthiophene (Japanese Journal of Applied Physics, Volume 30, L1938, 1991), and polyalkylfluorene (Japanese Journal of Applied Physics, Volume 30, L1941, 1991) are known as blue light emitting elements. These polymer-type elements cannot be applied to the vapor deposition method for forming the organic light-emitting thin film. Therefore, a thin film is usually formed directly on the substrate by a wet method.
[0006]
However, the wet method has problems that the film thickness uniformity of the organic thin film becomes insufficient due to the surface tension of the solution and that each organic layer dissolves at the interface when the organic layers are laminated. For this reason, the organic electroluminescent element obtained by this method has a problem that it is inferior in luminous efficiency and element durability.
[0007]
On the other hand, an organic thin film of an organic EL element is also used for printing. In the conventional printing method, the organic layer coating liquid is provided on the plate by a wet method, and the organic layer coating liquid is transferred to the film forming surface and dried to form the organic layer on the film forming surface. . However, in this method, in addition to the uniform formation of the organic layer coating liquid on the plate, the organic layer coating liquid must also be uniformly formed on the surface to be deposited, and the organic layer can be formed accurately and uniformly. It was difficult to do. Furthermore, it has been difficult to accurately form a fine pixel pattern at a predetermined position.
[0008]
On the other hand, as a method of forming an organic thin film of an organic EL element, for example, Patent Document 1 proposes a method of thermally transferring an organic thin film with a laser using a donor sheet having an organic thin film and a photothermal conversion layer.
[0009]
[Patent Document 1]
WO00 / 41893 pamphlet
[0010]
[Problems to be solved by the invention]
However, in the case of the thermal transfer method as in Patent Document 1, there is a problem that a gas is involved in the bonding interface of the organic layer. Depending on the interface state of the organic layer, the light emission efficiency and durability of the organic EL element and the uniformity of the light emitting surface are different. Therefore, if gas is involved in the bonding interface of the organic layer, the element function is deteriorated.
[0011]
In addition, when an organic thin film is transferred from a donor by thermal writing in a pattern using a thermal head or laser used in the printing technology field, temperature distribution occurs around the pattern due to thermal diffusivity, and the organic thin film pattern The contour is not cut cleanly from the donor side. For this reason, there is a problem in that the obtained organic EL element has a variation in light emission amount, an electrical failure or a defect due to a thin film fragment, and a deterioration in durability. There is also a problem that the yield decreases due to poor alignment between the substrate and the thermal head or laser.
[0012]
As a method for producing a patterned organic layer, a relief dyeing method, a pigment dispersion method, an electrodeposition method, a vacuum deposition method, an ink jet method, an offset printing method, and the like have been proposed.
[0013]
In the relief dyeing method, a predetermined pattern is formed on the organic layer using a photosensitive resist, and then the substrate on which the organic layer is formed is immersed in a dyeing solution and colored.
[0014]
The pigment dispersion method is a method in which a pattern in which a pigment is dispersed in a photosensitive resist is applied on a substrate, exposed and developed to form a pattern.
[0015]
The electrodeposition method is a method of electrodepositing a predetermined pattern on an electrode. However, if an organic layer containing a multicolored luminescent material is patterned on a substrate by a relief dyeing method, a pigment dispersion method, or an electrodeposition method, the organic layer is damaged and the driving energy required for light emission is reduced. There is a problem that the power consumption increases.
[0016]
When a vacuum vapor deposition method in which patterning is performed by heating and evaporating a light emitting material with a mask placed between the organic layer and the vapor deposition source is applied to a large area organic electroluminescent device, the mask may be distorted by heat. In addition, in order to clean the used mask, it is necessary to clean in a vacuum or to take out the vacuum once and clean it, and then return to the vacuum, which is not suitable for mass production. In addition, in the inkjet method and the offset printing method, it is difficult to select a solvent when laminating an organic layer containing a light emitting material, and the laminated organic layer is mixed at the bonding interface. There is a problem that decreases.
[0017]
Accordingly, an object of the present invention is to easily form a patterned organic layer on a substrate and to reduce an organic electroluminescent device excellent in film thickness uniformity, light emission efficiency, light emission uniformity and durability of the organic layer. It is providing the method and organic electroluminescent element which manufacture at low cost.
[0018]
[Means for Solving the Problems]
As a result of diligent research in view of the above object, the present inventor provided an organic layer on a plate having a predetermined pattern portion, transferred the organic layer to the first substrate, and further bonded to the second substrate. Discovered that organic electroluminescent devices with excellent organic layer thickness uniformity, light emission efficiency, light emission uniformity, and durability can be produced at low cost while a patterned organic layer can be easily formed on a substrate. The present invention has been conceived.
[0019]
That is, the method for producing an organic electroluminescent device of the present invention uses a plate having at least one organic layer in at least a pattern portion, and includes an organic layer side of the plate, an electrode side of a first substrate having at least an electrode, The plate and the first substrate are stacked so as to face each other, and after performing at least one of a heat treatment and a pressure treatment, the plate is peeled off to remove the plate on the electrode side of the first substrate. A method of manufacturing an organic electroluminescent element including a step of transferring an organic layer, wherein the second substrate having at least one electrode and at least one of the organic layer after the step of transferring the organic layer is provided. It is characterized by being bonded to a substrate.
[0020]
It is preferable that after the step of transferring the organic layer, there is a step of further transferring at least one organic layer on the organic layer provided on the first substrate.
[0021]
The plate is preferably a relief plate. The organic layer preferably contains at least a light emitting organic compound or a carrier transporting organic compound. It is preferable that the thermal expansion coefficient of at least one of the first substrate and the second substrate is 20 ppm / ° C. or less.
[0022]
The first substrate and the second substrate preferably have electrodes on part or the entire surface on which the organic layer is formed. At least one of the electrode on the first substrate and the electrode on the second substrate is preferably transparent. At least one of the first substrate and the second substrate is preferably transparent. Either or either of the first substrate and the second substrate has an organic layer (for example, an organic layer provided by a coating method) other than the organic layer transferred by a peeling transfer method on the surface of the film formation surface. May be.
[0023]
In the production method of the present invention, a plurality of transfer materials having organic layers having the same or different compositions are used, or transfer materials having a plurality of organic layers having the same or different compositions are used on the first substrate. A plurality of organic layers can be transferred to the substrate.
[0024]
The organic electroluminescent element obtained by the production method of the present invention is excellent in the film thickness uniformity, light emission efficiency, light emission amount uniformity and durability of the organic layer. In the organic electroluminescence device, on the first substrate, an electrode, at least one organic layer including a light-emitting organic layer, a second electrode, and a second substrate are provided in this order. It is preferable that at least one of the second substrates is transparent, and the electrode of the transparent substrate is transparent.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below. First, the method for producing the organic electroluminescent device of the present invention will be described, then the transfer material will be described, and finally the organic electroluminescent device will be described.
[0026]
[1] Method for manufacturing organic electroluminescent element
The method for producing an organic electroluminescent element of the present invention comprises producing a transfer material by forming at least one organic layer on a plate, and transferring the organic material side so that the organic layer side faces the film-forming surface of the first substrate. The organic layer is transferred to the film-forming surface of the first substrate by peeling the plate by applying heat treatment and / or pressure treatment on the first substrate (peeling transfer method) .
[0027]
After the organic layer is formed by the peeling transfer method, it is preferable that the second substrate provided with the electrode is bonded so that the electrode side and the organic layer of the first substrate face each other. One transfer material may be used, or two or more transfer materials having organic layers having the same or different composition may be used.
[0028]
In the peeling transfer method, the organic layer is softened by heating and / or pressurizing the transfer material and adhered to the film formation surface of the substrate, and then the plate is peeled off, so that only the organic layer is formed. This is a method (peeling transfer method) that is left on the substrate. As a means for heating and / or pressurizing, a known method can be used. For example, a laminator, an infrared heater, a thermal head, a hot plate, a press machine, or the like can be used. As the laminator, for example, First Laminator VA-400III (manufactured by Taisei Laminator Co., Ltd.), a thermal head for thermal transfer printing, a hot plate press machine, or the like can be used.
[0029]
The transfer temperature is not particularly limited and can be changed depending on the material of the organic layer and the heating member, but is generally preferably 40 to 250 ° C, more preferably 50 to 200 ° C, and particularly preferably 60 to 180 ° C. However, the preferable range of the transfer temperature relates to the heat resistance of the heating member, the transfer material, and the first substrate, and changes as the heat resistance is improved. When two or more kinds of transfer materials are used, it is preferable that the transfer temperature of the transfer material to be transferred first is equal to or higher than the transfer temperature of the transfer material to be transferred next. When a transfer material having two or more organic layers is used, it is preferable that the transfer temperature of the organic layer to be transferred first is equal to or higher than the transfer temperature of the organic layer to be transferred next.
[0030]
The transfer pressure is not particularly limited and can be changed depending on the material of the organic layer and the pressure member, but generally 0 to 10 t / cm.²Is preferred, 0 to 5 t / cm²Is more preferable, 0 to 2 t / cm²Is particularly preferred. However, the preferable range of the transfer pressure is related to the pressure resistance of the pressure member, the transfer material, and the first substrate, and changes as the pressure resistance improves.
[0031]
The glass transition temperature or flow start temperature of the organic layer or the polymer component thereof is preferably 40 ° C. or higher and transfer temperature + 40 ° C. or lower. Two or more organic layers to be transferred may contain at least one common component.
[0032]
Prior to transfer, the first substrate and / or transfer material may be preheated. The preheating temperature of the first substrate and / or transfer material is preferably 30 ° C. or higher and transfer temperature + 20 ° C. or lower. The temperature at which the plate is peeled off is preferably 50 ° C. or higher and the transfer temperature or lower.
The transferred organic layer may be heated again after peeling the plate. When the transfer material is superimposed on the first substrate and heated so that the organic layer faces the film formation surface of the first substrate, pressurization may also be performed.
[0033]
When the transfer material is overlaid on the first substrate so that the organic layer faces the film-forming surface of the first substrate, it is preferable to increase the angle of entry of the transfer material with respect to the first substrate so that bubbles such as bubbles are wound. This is preferable because of less embedding. When the plate is peeled off from the organic layer transferred onto the first substrate, it is preferable that the peeling angle of the plate with respect to the organic layer is relatively large.
[0034]
In the present invention, a plurality of organic layers can be laminated on the first substrate by repeating the transfer / peeling step. The plurality of organic layers may be the same composition or different. In the case of the same composition, there is an advantage that it is possible to prevent the layer from coming off due to transfer failure or peeling failure. In the case where different organic layers are provided, the light emission efficiency can be improved by separating the functions. For example, a transparent conductive layer / light-emitting organic layer / electron transporting organic layer / electron injection layer / back electrode, transparent conductive layer / hole injection layer / hole are formed on the film formation surface of the first substrate by the transfer method of the present invention. The transporting organic layer / the light emitting organic layer / the electron transporting organic layer / the electron injection layer / the back electrode can be laminated in this order or in the reverse order. The organic layer preferably has at least a light emitting organic compound or a carrier transporting organic compound.
[0035]
It is preferable to reheat and / or repressurize the organic layer transferred to the first substrate or the new organic layer transferred to the previously transferred organic layer as necessary. By reheating and / or repressurization, the organic layer is more closely attached to the first substrate or the previously transferred organic layer. The reheating temperature is preferably in the range of the transfer temperature ± 50 ° C.
The repressurization is preferably in the range of ± 100% of the transfer pressure.
[0036]
In order to prevent the previous transfer layer from being reversely transferred to the next transfer layer, a surface treatment may be performed between the previous transfer step and the next transfer step in order to improve adhesion to the film formation surface.
Examples of such surface treatment include activation treatment such as corona discharge treatment, flame treatment, glow discharge treatment, and plasma treatment. When the surface treatment is used in combination, the transfer temperature of the previous transfer material may be lower than the transfer temperature of the next transfer material unless reverse transfer is performed.
[0037]
An apparatus for manufacturing an organic electroluminescent element includes an apparatus for feeding a transfer material in which an organic layer is formed on a plate by a vacuum film-forming method or a wet method, and a first substrate while heating and / or pressurizing the transfer material. A structure having an apparatus for transferring the organic layer to the film formation surface of the first substrate by pressing against the film formation surface and an apparatus for peeling the plate from the organic layer after the transfer are preferable.
[0038]
The manufacturing apparatus preferably has means for preheating the transfer material and / or the first substrate before feeding to the transfer apparatus. Moreover, you may have a cooling device in the back | latter stage of a transfer apparatus.
An entrance angle adjusting unit for increasing the entrance angle of the transfer material with respect to the first substrate may be provided on the front surface of the transfer device, and a peeling angle with respect to the organic layer of the plate is provided on the rear surface of the transfer device or the cooling device. You may provide the peeling angle adjustment part for enlarging. Details of the method and apparatus for producing the organic electroluminescent element described above are described in JP-A No. 2002-260854, JP-A No. 2002-289346, and the like.
[0039]
[2] Transfer material
(1) Configuration
At least one organic layer is formed on the plate. The transfer material preferably has a configuration in which an organic layer is uniformly formed on a support surface of a plate having a predetermined pattern portion. When transferring a plurality of organic layers onto the film-forming surface of the first substrate, an independent transfer material may be prepared for each organic layer, or each organic layer may be arranged on the plate in the surface order (stacking order). A single transfer material provided side by side may be manufactured. If the latter transfer material is used, a plurality of organic layers can be transferred continuously without changing the transfer material.
[0040]
If a transfer material in which two or more organic layers are laminated in advance on a plate is used, a multilayer film can be formed on the film formation surface of the first substrate in one transfer step. When two or more organic layers are laminated on the plate in advance, if the interface between the laminated organic layers is not uniform, the movement of holes and electrons will be uneven. Choose the law carefully. The film forming method is not particularly limited as long as a thin film can be formed. Examples thereof include a wet method and a dry method (eg, vapor deposition method).
[0041]
When transferring multiple organic layers by using transfer materials with multiple organic layers arranged side by side (stacking order) or using multiple transfer materials, alignment of the transfer material and the first substrate Therefore, the transfer material and the first substrate may be marked. As the marking method, a generally known method can be appropriately used.
[0042]
(2) Version
As the plate, a normal printing relief plate, a planographic plate, an intaglio plate or a stencil plate can be used. Although FIGS. 1-9 shows the example of the plate | version | printing which has an organic layer in a pattern part at least, it is not limited to these. 1 and 2 are a cross-sectional view and a plan view showing an example of a relief printing plate having an organic layer. As shown in FIG. 1 and FIG. 2, the relief plate is such that a predetermined pattern portion 2 and a non-pattern portion 3 are on the same plane of the plate 1, and the non-pattern portion 3 is depressed more than the pattern portion 2. Is. The organic layer 4 is formed on the pattern portion 2 including at least the convex portion 11. When the organic layer 4 is formed by a coating method described later, it is preferably formed only on the pattern portion 2. When the organic layer 4 is formed by a vacuum film forming method or a vapor deposition method to be described later, the organic layer 4 is formed on the pattern portion 2 and the non-pattern portion 3 as shown in FIG.
[0043]
When using a relief plate, the film-forming surface of the first substrate contacts the pattern portion of the relief plate and does not contact the non-pattern portion. As letterpress plates produced by mechanical methods, letterpress plates (typesetting with letterpress. Sometimes letterpress plates may be incorporated into letterpress plates), lead plates produced by pouring alloys with letterpress plates, wood plates, plastic plates There are rubber plates and so on. As a letterpress plate produced by a chemical method, there is one in which an original plate made of a letterpress is electroplated.
[0044]
As the relief plate used in the present invention, an engraving relief plate obtained by engraving on a glass plate or a metal foil, and an etching relief plate obtained by etching corroding a predetermined portion of a copper plate or a copper cylindrical surface using a chemical solution are preferable. An engraving letterpress is an electronic engraving obtained by electronic engraving that engraves a plate in response to the strength of the current by means of a diamond needle on a plate material by causing the engraving device to function by the current generated by photoelectrically scanning the document. Letterpress may be mentioned. Examples of the engraving letterpress include a laser engraving letterpress that engraves a plate on a plate material using laser light. A line drawing letterpress is applied to form a line drawing without gradation, and a mesh letterpress or electronic engraving letterpress is applied to form an image that requires gradation such as a photograph.
[0045]
The pattern portion of the relief plate only needs to be arranged so that the transferred organic layer has a desired pattern. For example, as a relief plate, the organic layer forming surface is rectangular, square or trapezoidal convex on the plate-shaped main body (for example, the organic layer forming surface of the convex 11 of the relief plate shown in FIGS. 1 and 2 is rectangular). There is a case where a large number of them are arranged. When such a relief printing plate is used, the total area of the organic layer forming surface of the projections varies depending on the transfer conditions and pattern shape, but it is sufficient that the projections do not collapse during transfer, and the surface area of the plate surface is reduced. When it is set to 100, it is preferably 5 to 100, more preferably 5 to 95.
The height of the convex portion is preferably 0.5 to 50 μm. There exists a possibility that an organic layer may be transcribe | transferred to parts other than a pattern as the height of the convex part 12 is less than 0.5 micrometer.
[0046]
FIG.4 and FIG.5 is sectional drawing and the top view which show the example of the intaglio which has an organic layer. As shown in FIGS. 4 and 5, the intaglio is that the predetermined pattern portion 2 and the non-pattern portion 3 are on the same plane, and the pattern portion 2 is depressed more than the non-pattern portion 3, opposite to the relief plate. Of the type. The organic layer 4 is formed in the pattern portion 2 including at least the concave portion 12. When the intaglio is used, the organic layer 4 is formed on the entire surface of the intaglio as shown in FIG. 6, the organic layer 4 of the non-pattern part 3 is removed (wiped or scraped off), and the organic layer 4 is left only in the concave part 12. . As an intaglio produced by a mechanical method, there is an engraved intaglio obtained by engraving a copper plate or the like. As the engraving intaglio, an electronic engraving gravure plate obtained by the above-mentioned electronic engraving can be mentioned. Examples of engraving intaglio include laser engraving intaglio. As an intaglio plate produced by a chemical method, there is a gravure plate for a photographic image obtained by etching that corrodes a predetermined portion of a copper plate or a copper cylindrical surface using a chemical solution.
[0047]
7 and 8 are a cross-sectional view and a plan view showing an example of a planographic plate having an organic layer. As shown in FIGS. 7 and 8, the lithographic plate is configured such that the predetermined pattern portion 2 and the non-pattern portion 3 are macroscopically coplanar. For example, when an organic layer is formed on a lithographic plate using a coating solution for an organic layer, a lyophilic treatment is performed on the portion of the plate surface of the substrate made of a glass plate or metal foil to form a pattern portion, thereby forming a non-pattern portion. Liquid repellent treatment is applied to the part to be processed. When the organic layer coating solution 4 ′ is applied to the entire surface of the lithographic plate thus produced as shown in FIG. 9, the organic layer coating solution 4 ′ remains only in the lyophilic pattern portion 2. As shown in FIGS. 7 and 8, the organic layer 4 is formed only on the pattern portion 2.
[0048]
Thus, the lithographic plate is produced by a chemical method and cannot be produced by a mechanical method. As the lithographic plate, a lithographic plate mainly composed of calcium carbonate, a metallic lithographic plate using a plate of zinc, aluminum or the like, a multilayer lithographic plate in which a plate material composed of two different metal layers is provided on a supporting plate, and gelatin are mainly used. Examples thereof include a collotype plate in which a photosensitive solution as a component is applied to a glass substrate or the like. When a corotype plate is used, the exposed portion is cured when the negative is baked. Therefore, the pattern portion can be formed by absorbing the organic layer coating solution in the non-cured portion (may be swollen by absorption). When using a lithographic plate, the film-forming surface of the first substrate is in contact with almost the entire surface of the transfer material.
[0049]
The stencil is in the form of a film or plate in which a predetermined pattern part penetrates the front and back. When a stencil is used, an organic layer is filled in the penetrating portion and used as a dry film.
Examples of the stencil include a copying plate made of a wire net having a pattern portion formed in a mesh shape, a silk screen plate made of a silk net filled with a resin in a non-pattern portion, and the like.
[0050]
A relief plate is preferable as the plate from the viewpoint that bubbles are difficult to enter during transfer, a material loss during the plate production is small, a material loss during the transfer material production is small, and the like.
[0051]
When using a relief plate or an intaglio plate so that a predetermined organic layer pattern can be accurately formed on the first substrate, the relief portion of the relief plate and the recess portion of the intaglio plate are directed toward the back surface (the surface opposite to the support surface). It is preferably tapered.
[0052]
The base material for producing the plate is not particularly limited as long as it is chemically and thermally stable. Specific examples of the substrate for producing the plate include a plate or thin film made of glass; metal foil such as aluminum foil, copper foil, stainless steel foil, gold foil, silver foil; polyimide, liquid crystalline polymer, fluororesin [for example, 4 fluorine Polyethylene resin (PTFE), trifluoroethylene chloride resin (PCTFE)], polyester [eg, polyethylene terephthalate, polyethylene naphthalate (PEN)], polycarbonate, polyethersulfone (PES), polyolefin (eg, polyethylene, polypropylene), poly Examples thereof include a plastic sheet made of arylate, hard vinyl chloride or the like.
[0053]
The plate may be composed of a single material selected from the material group, but may be a laminate selected from the material group. In particular, the plate is preferably composed of a glass plate, an aluminum foil, a copper foil, a stainless steel foil, or a laminate containing any of these from the viewpoint of ease of processing and cost. There is no particular limitation on the thickness of the plate, and it can be appropriately selected according to the specifications incorporated in the production facility. However, it is preferably as thick as possible so that it can withstand repeated use. The thickness of the plate is generally 0.5 mm to 5 m although it depends on the material. The structure and size of the plate are not particularly limited, and can be appropriately selected according to the specifications and purpose of the production equipment.
[0054]
The contact angle of pure water on the surface (support surface) on which the organic layer of the plate is formed (hereinafter simply referred to as “contact angle” unless otherwise specified) is preferably 50 ° or more, and 60 ° or more. Is more preferable, and 70 ° or more is particularly preferable. When a plate having a contact angle of less than 50 ° is used, the degree of adhesion with the plate of the organic layer is increased, so that transferability may be deteriorated. When the organic layer is provided by coating, depending on the composition of the coating solution, if the contact angle exceeds 90 °, coating unevenness may occur, which is not preferable. However, when the organic layer is provided by a dry method such as a vacuum film forming method or a transfer peeling method, there is no particular limitation on the upper limit of the contact angle.
[0055]
In this specification, the “contact angle” is an angle formed by a tangent line drawn from a contact point between a support surface of a plate and a water droplet of pure water to the water droplet and the support surface. The method for measuring the contact angle is not particularly limited as long as it is a method using a general contact angle measuring device capable of measuring a water droplet that has been left immediately after dropping. Examples of the contact angle measuring machine include a contact angle meter (model number CA-X, image processing type) manufactured by Kyowa Interface Science Co., Ltd. As a measurement environment for the contact angle, it is preferable that the temperature is 21 to 24 ° C., the relative humidity is 45 to 55%, and the sample amount is 1 pL to 0.1 mL. In addition, when making sample amount into 1 pL or more and less than 1 microliter, it is preferable to use model number MCA-1 by Kyowa Interface Science Co., Ltd. as a contact angle meter.
[0056]
In order to make the contact angle in a range of 50 ° or more, the support surface of the plate may be subjected to surface water repellent treatment. An example of the surface water repellent treatment is a fluorination treatment. As the fluorination treatment method, fluorocarbon gas (CF₄A method of performing plasma treatment using a gas or the like, a method of exposing to a vapor of a fluorinated alkyl coupling agent, and the like. Examples of fluorinated alkyl coupling agents include perfluoroalkyl functional silanes. As the perfluoroalkyl functional silane, perfluoroalkyltrimethoxysilane is preferred.
[0057]
A release layer containing a component having a release effect (release agent) may be provided on the support surface of the plate. By providing a release layer on the support surface of the plate, after the transfer material is overlaid on the first substrate and subjected to heat treatment and / or pressure treatment, the organic layer is not fused to the plate side when the plate is peeled off, The organic layer can be efficiently transferred to the first substrate.
[0058]
The maximum height Rmax of the surface roughness defined by JIS B0601-1982 of the support surface of the plate is preferably 0 or more and 50 or less when the film thickness of the organic layer transferred to the transfer material is 100. . When the maximum height Rmax exceeds 50, not only the transfer rate is lowered, but also an organic layer is formed by a peeling transfer method, resulting in poor film formation (for example, poor adhesion at the bonding interface) and reduced film strength. In the produced organic EL element, non-uniform performance (for example, light emission failure due to short circuit or missing) occurs. The maximum height Rmax is preferably 0.0001 to 25, more preferably 0.01 to 25, and particularly preferably 0.01 to 10.
Examples of the method for measuring the maximum height Rmax include atomic force microscopy, confocal microscopy, stylus method, optical microscopic interference method, multiple interference method, optical cutting method, and the like. Preferably confocal microscopy is used.
[0059]
In order to adjust the maximum height Rmax, a smooth layer may be provided on the support surface of the plate. The material for constituting the smooth layer is not particularly limited as long as it does not deteriorate the light emission performance of the organic electroluminescent element. As a material for constituting the smooth layer, at least one selected from the group consisting of a thermosetting organic compound, an ultraviolet curable organic compound, an electron beam curable organic compound, an inorganic oxide, and an inorganic nitride is preferably used.
[0060]
Before the surface water-repellent treatment described above, or before the release layer or the smooth layer is provided, a pretreatment may be applied to the support surface of the plate. Examples of the pretreatment include surface treatment by providing an undercoat layer or performing activation treatment such as corona discharge treatment, plasma treatment, ozone treatment, flame treatment, and glow discharge treatment. This improves the adhesion between the water repellent coating, the release layer or the smooth layer and the support surface of the plate.
[0061]
(3) Organic layer
The organic layer is a layer that constitutes an organic electroluminescent element together with a pair of electrodes, and contains an organic compound as a main component. From each characteristic, a luminescent organic layer, an electron transporting organic layer, a hole transporting organic layer, Examples thereof include an electron injection layer and a hole injection layer. In addition, various layers for improving color developability can be exemplified. Specific examples of the compound used for each layer are described in, for example, “Monthly Display” October 1998 issue “Organic EL Display” (Techno Times).
[0062]
The glass transition temperature of the organic layer itself or the polymer component therein is preferably 40 ° C. or higher to transfer temperature + 40 ° C. or lower, more preferably 50 ° C. or higher to transfer temperature + 20 ° C. or lower, and particularly preferably 60 ° C. or higher to transfer temperature or lower. . Further, the flow start temperature of the organic layer itself and the polymer component in the transfer material is preferably 40 ° C. or higher to transfer temperature + 40 ° C. or lower, more preferably 50 ° C. or higher to transfer temperature + 20 ° C. or lower, and 60 ° C. or higher to transfer temperature. Below the temperature is particularly preferred. The glass transition temperature can be measured by a differential scanning calorimeter (DSC). The flow start temperature can be measured using, for example, a flow tester CFT-500 manufactured by Shimadzu Corporation.
[0063]
(A) Luminescent organic layer
The luminescent organic layer contains at least one luminescent compound. The light emitting compound is not particularly limited, and may be a fluorescent light emitting compound or a phosphorescent light emitting compound. Further, a fluorescent compound and a phosphorescent compound may be used at the same time. In the present invention, it is preferable to use a phosphorescent compound from the viewpoint of light emission luminance and light emission efficiency.
[0064]
Fluorescent compounds include benzoxazole derivatives, benzimidazole derivatives, benzothiazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalimide derivatives, coumarin derivatives, perylene derivatives, perinone derivatives, oxalates. Diazole derivatives, aldazine derivatives, pyralidine derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives, quinacridone derivatives, pyrrolopyridine derivatives, thiadiazolopyridine derivatives, styrylamine derivatives, aromatic dimethylidene compounds, metal complexes (metals of 8-quinolinol derivatives) Complex, rare earth complex, etc.), polymer light emitting compound (polythiophene derivative, polyphenylene derivative, polyphenylene vinylene derivative, Rifuruoren derivatives) and the like can be used. These may be used alone or in admixture of two or more.
[0065]
The phosphorescent compound is preferably a compound that can emit light from triplet excitons, and orthometalated complexes and porphyrin complexes are preferable. Of the porphyrin complexes, a porphyrin platinum complex is preferred. The phosphorescent compounds may be used alone or in combination of two or more.
[0066]
The orthometalated complex referred to in the present invention is a material described in Akio Yamamoto, “Organic Metal Chemistry Fundamentals and Applications,” pages 150 and 232, Houhuabosha (1982), H.C. Yersin's “Photochemistry and Photophysics of Coordination Compounds”, pages 71-77 and pages 135-146, Springer-Verlag (1987), etc. The ligand forming the ortho-metalated complex is not particularly limited, but a 2-phenylpyridine derivative, a 7,8-benzoquinoline derivative, a 2- (2-thienyl) pyridine derivative, a 2- (1-naphthyl) pyridine derivative or A 2-phenylquinoline derivative is preferred. These derivatives may have a substituent. Moreover, you may have another ligand other than these essential ligands for ortho metalation complex formation. As the central metal forming the orthometalated complex, any transition metal can be used. In the present invention, rhodium, platinum, gold, iridium, ruthenium, palladium and the like are preferable. An organic compound layer containing such an orthometalated complex is excellent in light emission luminance and light emission efficiency. Specific examples of the orthometalated complex are described in paragraph Nos. 0201 to 0231 of JP-A No. 2002-319491.
[0067]
The orthometalated complex used in the present invention can be obtained from Inorg. Chem. , 30, 1685, 1991, Inorg. Chem. , 27, 3464, 1988, Inorg. Chem. , 33, 545, 1994, Inorg. Chim. Acta, 181, 245, 1991; Organomet. Chem. , 335, 293, 1987; Am. Chem. Soc. , 107, 1431, 1985 and the like.
[0068]
Although content in particular of the luminescent compound in a luminescent organic layer is not restrict | limited, For example, it is preferable that it is 0.1-70 mass%, and it is more preferable that it is 1-20 mass%. If the content of the luminescent compound is less than 0.1% by mass or exceeds 70% by mass, the effect may not be sufficiently exhibited.
[0069]
The light-emitting organic layer may contain a host compound, a hole transport material, an electron transport material, an electrically inactive polymer binder, and the like as necessary. Note that the functions of these materials may be achieved simultaneously by one compound. For example, a carbazole derivative not only functions as a host compound but also functions as a hole transport material.
[0070]
A host compound is a compound that causes energy transfer from its excited state to the luminescent compound, and as a result, causes the luminescent compound to emit light. Specific examples include carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives. , Fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidene compounds, porphyrin compounds, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyran dioxide oxide Derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, and heterocyclic tetra Rubonic acid anhydride, phthalocyanine derivative, metal complex of 8-quinolinol derivative, metal phthalocyanine, metal complex having benzoxazole or benzothiazole as a ligand, polysilane compound, poly (N-vinylcarbazole) derivative, aniline copolymer , Conductive polymers such as thiophene oligomers and polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, and the like. A host compound may be used individually by 1 type, or may use 2 or more types together. The content of the host compound in the light emitting organic layer is preferably 0 to 99.9% by mass, and more preferably 0 to 99.0% by mass.
[0071]
The hole transport material is not particularly limited as long as it has any one of the function of injecting holes from the anode, the function of transporting holes, and the function of blocking electrons injected from the cathode. Or a polymer material. Specific examples include carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives. Fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidene compounds, porphyrin compounds, polysilane compounds, poly (N-vinylcarbazole) derivatives, aniline copolymers, Conductive polymer such as thiophene oligomer, polythiophene, polythiophene derivative, polyphenylene derivative, polyphenylene vinylene derivative, polyfluor Ren derivatives and the like. These may be used alone or in combination of two or more. The content of the hole transport material in the light-emitting organic layer is preferably 0 to 99.9% by mass, and more preferably 0 to 80.0% by mass.
[0072]
The electron transport material is not particularly limited as long as it has any one of the function of injecting electrons from the cathode, the function of transporting electrons, and the function of blocking holes injected from the anode. Specific examples thereof include, for example, triazole derivatives, oxazole derivatives, oxadiazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, Stylylpyrazine derivatives, heterocyclic tetracarboxylic anhydrides such as naphthaleneperylene, metal complexes such as phthalocyanine derivatives and 8-quinolinol derivatives, metal complexes having metallophthalocyanine, benzoxazole, benzothiazole, etc. as ligands, aniline copolymers , Conductive polymers such as thiophene oligomers and polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, and the like. These may be used alone or in combination of two or more. The content of the electron transport material in the light-emitting organic layer is preferably 0 to 99.9% by mass, and more preferably 0 to 80.0% by mass.
[0073]
As polymer binder, polyvinyl chloride, polycarbonate, polystyrene, polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate, ABS resin, Polyurethane, melamine resin, unsaturated polyester, alkyd resin, epoxy resin, silicone resin, polyvinyl butyral, polyvinyl acetal, etc. can be used. These may be used alone or in combination of two or more. The light-emitting organic layer containing a polymer binder can be easily applied to a large area by a wet film forming method.
[0074]
The thickness of the light emitting organic layer is preferably 10 to 200 nm, and more preferably 20 to 80 nm. When the thickness exceeds 200 nm, the driving voltage may increase. Meanwhile 10
If it is less than nm, the organic electroluminescence device may be short-circuited.
[0075]
(B) Hole transportable organic layer
The organic electroluminescent element may have a hole transporting organic layer made of the hole transport material described in the above (a) as necessary. The hole transporting organic layer may contain the polymer binder described in the above (a). The thickness of the hole transporting organic layer is preferably 10 to 200 nm, and more preferably 20 to 80 nm. When the thickness exceeds 200 nm, the driving voltage may increase. When the thickness is less than 10 nm, the organic electroluminescence device may be short-circuited.
[0076]
(C) Electron transporting organic layer
The organic electroluminescent element may have an electron transporting organic layer made of the electron transport material described in the above (a) as necessary. The electron transporting organic layer may contain the polymer binder described in the above (a). The thickness of the electron transporting organic layer is preferably 10 to 200 nm, and more preferably 20 to 80 nm. When the thickness exceeds 200 nm, the driving voltage may increase. When the thickness is less than 10 nm, the organic electroluminescence device may be short-circuited.
[0077]
(D) Solvent for coating solution
When the above organic layer is applied and formed by a wet film formation method, the solvent used for dissolving the material of the organic layer and adjusting the coating solution is not particularly limited, and includes a hole transport material, an orthometalated complex, It can select suitably according to types, such as a host material and a polymer binder. Examples of the solvent include halogen solvents such as chloroform, carbon tetrachloride, dichloromethane, 1,2-dichloroethane, and chlorobenzene; ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, n-propyl methyl ketone, and cyclohexanone; benzene, toluene, Aromatic solvents such as xylene; ester solvents such as ethyl acetate, n-propyl acetate, n-butyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, diethyl carbonate; ether solvents such as tetrahydrofuran and dioxane; Amide solvents such as dimethylformamide and dimethylacetamide; dimethyl sulfoxide; water and the like. In the coating solution, the solid content with respect to the solvent is not particularly limited, and the viscosity of the coating solution can be arbitrarily selected according to the wet film forming method.
[0078]
When forming a plurality of organic layers, in addition to the transfer method of the present invention, a dry film forming method such as a vapor deposition method or a sputtering method; a dipping method, a spin coating method, a dip coating method, a casting method, a die coating method, or a roll coating method. Further, wet film forming methods such as a bar coating method and a gravure coating method; a printing method and the like can be used in combination.
[0079]
(4) Formation of organic layer on plate
The method for forming the organic layer on the plate is different depending on whether the organic layer contains a high molecular compound as the organic layer main component or binder and a case where the organic layer is made of a low molecular compound. When the organic layer contains a polymer compound as a main component of the organic layer or a binder, it is preferably formed on the plate by a wet method. For this purpose, the organic layer material is dissolved in an organic solvent at a desired concentration, and the obtained solution is applied on the plate. The coating method is not particularly limited as long as a dry film thickness of the organic layer is 200 nm or less and a uniform film thickness distribution is obtained. Spin coating method, gravure coating method, dip coating method, casting method, die coating method, roll coating Method, bar coating method, extrusion coating method, inkjet coating method and the like. Among them, the extrusion coating method with high productivity by roll-to-roll is preferable.
[0080]
When the organic layer is composed of a low-molecular compound, the formation method is not particularly limited as long as a dry film thickness of the organic layer is 200 nm or less and a uniform film thickness distribution is obtained. In addition to the coating method when using a polymer compound, A vacuum film formation method or a vapor deposition method can also be used. For example, as a physical vacuum film forming method, a vacuum evaporation method, an electron beam evaporation method, a laser ablation MBE method, a MOMBE method, a reactive evaporation method, an ion plating method, a cluster ion beam method, a glow discharge sputtering method, an ion beam A sputtering method, a reactive sputtering method, etc. can be mentioned. Examples of the chemical vacuum film forming method include a thermal CVD method, an MOCVD (MOVPE) method, an RF plasma CVD method, an ECR plasma CVD method, a photo CVD method, a laser CVD method, and a mercury sensitization method. Of these, vacuum deposition is preferred. Details of these methods are described in “[Picture] Thin Film Technology” edited by the Surface Science Society of Japan.
[0081]
[3] Organic electroluminescence device
(1) Configuration
The organic electroluminescent element of the present invention is composed of at least a transparent substrate, a transparent electrode layer, at least one organic layer, a transparent or opaque electrode layer, and a transparent or opaque substrate in this order. One layer is preferably a light-emitting organic layer. Furthermore, the overall structure of the organic electroluminescent device is as follows: first substrate / transparent conductive layer / luminescent organic layer / back electrode / second substrate, first substrate / transparent conductive layer / luminescent organic layer / electron transport property. Organic layer / back electrode / second substrate, first substrate / transparent conductive layer / hole transporting organic layer / light emitting organic layer / electron transporting organic layer / back electrode / second substrate, first substrate / Transparent conductive layer / hole transporting organic layer / luminescent organic layer / back electrode / second substrate, first substrate / transparent conductive layer / luminescent organic layer / electron transporting organic layer / electron injection layer / back electrode / Second substrate, first substrate / transparent conductive layer / hole injection layer / hole transport organic layer / light emitting organic layer / electron transport organic layer / electron injection layer / back electrode / second substrate, etc. in this order A laminated structure is mentioned. The stacked configuration between the first substrate and the second substrate may be the reverse of the above example. The luminescent organic layer contains a fluorescent luminescent compound and / or a phosphorescent luminescent compound, and light emission is usually extracted from the transparent conductive layer. Specific examples of the compound used for each layer are described in, for example, “Monthly Display” October 1998 issue “Organic EL Display” (Techno Times).
[0082]
(2) Substrate
(A) First substrate
The first substrate has a function as a support to which an organic layer of a transfer material is transferred by a peeling transfer method. The thermal expansion coefficient of the first substrate is preferably several 20 ppm / ° C. or less. The thermal linear expansion coefficient can be measured by a method of heating at a constant rate and detecting a change in the length of the sample (for example, TMA method). When the coefficient of thermal expansion is larger than 20 ppm / ° C., the electrode or the organic layer may be peeled off due to the bonding process, heat during use, or the like, resulting in deterioration of durability.
[0083]
The base material for constituting the first substrate is not particularly limited as long as the coefficient of thermal linear expansion is several 20 ppm / ° C. or less, but is excellent in heat resistance, dimensional stability, solvent resistance, electrical insulation and workability. In addition, low air permeability and low moisture absorption are desirable. Specific examples include metal materials, inorganic materials, and plastic materials. When a metal material is used, it is preferable that an insulating layer be provided on one or both surfaces of the metal foil. It does not specifically limit as metal foil, Metal foil, such as aluminum foil, copper foil, stainless steel foil, gold foil, silver foil, can be used. Of these, aluminum foil or copper foil is preferred from the viewpoint of ease of processing and cost. Examples of the inorganic material include zirconia stabilized yttrium (YSZ) and glass. As the plastic material, polyimide or liquid crystal polymer can be particularly preferably used. Details on the properties and the like of these plastic materials are described in “Plastic Data Book” (Asahi Kasei Amidus Co., Ltd. “Plastics” editorial department). The first substrate may be formed of a single member or may be composed of two or more members. Among them, a laminate of a plastic material and a metal material is preferable in order to form a flexible organic electroluminescent element.
[0084]
The shape, structure, size and the like of the first substrate can be appropriately selected according to the use and purpose of the organic electroluminescence device. The shape is generally a plate or a continuous web. The structure may be a single layer structure or a laminated structure. The first substrate may be colorless and transparent or colored and transparent, but is preferably substantially colorless and transparent in that it does not scatter or attenuate light emitted from the light-emitting organic layer. Substantially colorless and transparent means that the light transmittance is 10% or more. The light transmittance of the first substrate is preferably 50% or more, particularly preferably 70% or more.
[0085]
A moisture permeation preventing layer (gas barrier layer) or an insulating layer may be provided on the surface of the first substrate on the electrode side, the surface opposite to the electrode, or both. In particular, when the first substrate is a metal material, the insulating layer is preferably used. At this time, it is preferable that the coefficient of thermal expansion of the moisture permeation preventing layer (gas barrier layer) and the insulating layer provided on the first substrate is also 20 ppm / ° C. or less. Metal oxides such as silicon oxide, germanium oxide, zinc oxide, aluminum oxide, titanium oxide, and copper oxide as materials for forming a moisture permeation preventive layer (gas barrier layer) or insulating layer having a thermal linear expansion coefficient of 20 ppm / ° C. or less Alternatively, metal nitrides such as silicon nitride, germanium nitride, and aluminum nitride are preferable, and these can be used alone or in combination of two or more.
[0086]
The thickness of the metal oxide and / or metal nitride inorganic insulating layer is preferably 10 to 1000 nm. If the inorganic insulating layer is thinner than 10 nm, the insulating property is too low. If the inorganic insulating layer is thicker than 1000 nm, cracks are likely to occur, pinholes are formed, and the insulation is reduced. A method for forming an insulating layer of metal oxide and / or metal nitride is not limited, and a dry method such as an evaporation method, a sputtering method, a CVD method, a wet method such as a sol-gel method, a metal oxide, and A method of dispersing and applying metal nitride particles in a solvent can be used.
[0087]
The insulating layer is made of the above-mentioned plastic material having a coefficient of thermal expansion of 20 ppm or less, polyester such as polyethylene terephthalate, polybutylene phthalate, polyethylene naphthalate, polystyrene, polycarbonate, polyethersulfone, polyarylate, allyldiglycol carbonate, polyimide, It can be formed of a plastic such as polycycloolefin, norbornene resin, poly (chlorotrifluoroethylene), or polyimide. When polyimide or the like is used as the insulating layer, it is preferable to laminate a sheet of polyimide or the like and an aluminum foil. The thickness of the polyimide sheet is preferably 10 to 200 μm. If the sheet of polyimide or the like is thinner than 10 μm, handling during lamination becomes difficult. When a sheet of polyimide or the like is thicker than 200 μm, flexibility is impaired and handling becomes inconvenient.
[0088]
The insulating layer may be provided only on one side of the metal foil, but may be provided on both sides. When provided on both surfaces, both surfaces may be metal oxides and / or metal nitrides, and both surfaces may be plastic insulating layers such as polyimide. Further, one side may be an insulating layer made of metal oxide and / or metal nitride, and the other side may be a polyimide sheet insulating layer. If necessary, a hard coat layer or an undercoat layer may be provided.
[0089]
The moisture permeability of the first substrate is a method based on JIS K7129B, and the value measured mainly by the MOCON method is 0.1 g / m.²-It is preferably not more than day, 0.05 g / m²More preferably less than day, 0.01 g / m²-It is particularly preferable that it is not more than day. Further, the oxygen permeability of the first substrate is a method based on the JIS K7126B method, and the value measured mainly by the MOCON method is 0.1 ml / m.²Day / atm or less is preferable, 0.05 ml / m²More preferably less than day · atm, 0.01 ml / m²It is particularly preferable that it is not more than day · atm.
[0090]
(B) Second substrate
The second substrate is provided on the upper surface of a single layer or a stacked organic layer formed on the first substrate by transfer by a peeling transfer method or repetition thereof. The requirements for the second substrate are the same as those for the first substrate described in (a) above. However, the second substrate preferably has the same physical property values (thermal linear expansion coefficient, light transmittance, moisture transmittance, oxygen permeability, etc.) as the first substrate. For example, the thermal expansion coefficients of the first substrate and the second substrate are preferably 20 ppm / ° C. or less. In order to suppress scattering and attenuation of light when light emission is extracted from the organic EL element, at least one of the first substrate and the second substrate is preferably colorless and transparent.
[0091]
The first substrate and the second substrate have at least electrodes. Furthermore, the first substrate and the second substrate may have at least one organic layer. The electrodes are provided on a part of or the entire surface of the first substrate and the second substrate in accordance with a desired pattern and element design.
[0092]
(3) Electrode
One of the pair of electrodes is preferably a transparent conductive layer and the other is a back electrode. Which of the anode and the cathode is used as the transparent conductive layer depends on the composition constituting the organic thin film element.
(A) Anode
The anode usually has a function of supplying holes to the organic electroluminescent layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light emitting device. The electrode can be appropriately selected from these electrodes.
[0093]
As a material for the anode, for example, a metal, an alloy, a metal oxide, an electrically conductive compound, a mixture thereof, or the like can be used, and a material having a work function of 4 eV or more is preferably used. Specific examples include tin oxide doped with antimony (ATO), tin oxide doped with fluorine (FTO), semiconductive metal oxides (tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), zinc oxide). Indium (IZO, etc.), metals (gold, silver, chromium, nickel, etc.), mixtures or laminates of these metals and conductive metal oxides, inorganic conductive substances (copper iodide, copper sulfide, etc.), organic conductivity Materials (polyaniline, polythiophene, polypyrrole, etc.) and laminates of this and ITO.
[0094]
The anode is a substrate support (first substrate) by a wet method such as a printing method or a coating method, a physical method such as a vacuum deposition method, a sputtering method or an ion plating method, a chemical method such as a CVD method or a plasma CVD method, etc. Or a second substrate). The formation method may be appropriately selected in consideration of suitability with the transparent conductive layer material. For example, when ITO is used as the anode material, a direct current or high frequency sputtering method, a vacuum deposition method, an ion plating method, or the like may be used. When an organic conductive material is used as the anode material, a wet film forming method may be used.
[0095]
The patterning of the anode layer can be performed by chemical etching using photolithography, physical etching using a laser, or the like. Alternatively, patterning may be performed by a vacuum evaporation method using a mask, a sputtering method, a lift-off method, a printing method, or the like.
[0096]
The thickness of the anode layer may be appropriately selected according to the material, but is usually 10 nm to 50 μm, preferably 50 nm to 20 μm. The anode resistance value is 10⁶Ω / □ or less is preferred, 10⁵Ω / □ or less is more preferable. 10⁵In the case of Ω / □ or less, a large-area light-emitting element with excellent performance can be obtained by installing a bus line electrode.
[0097]
The anode may be colorless and transparent, colored and transparent, or opaque. However, when the anode is a transparent anode and light emission is extracted from the transparent anode side, the transmittance is 60% or more. Is preferable, and 70% or more is more preferable. The transmittance can be measured according to a known method using a spectrophotometer. As the transparent anode, an electrode described in detail in “New development of transparent conductive film” (supervised by Yutaka Sawada, published by CMC, 1999) can be applied to the present invention. In particular, when a plastic substrate support having low heat resistance is used, it is preferable to use ITO or IZO as a transparent conductive layer material for forming a transparent anode, and form a film at a low temperature of 150 ° C. or lower.
[0098]
(B) Cathode
The cathode usually has a function of injecting electrons into the organic electroluminescent layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element. The electrode can be appropriately selected from these electrodes.
[0099]
As a material for forming the cathode, a metal, an alloy, a metal oxide, an electrically conductive compound, a mixture thereof, or the like can be used, and a material having a work function of 4.5 eV or less is preferably used. Specific examples include alkali metals (Li, Na, K, Cs, etc.), alkaline earth metals (Mg, Ca, etc.), gold, silver, lead, aluminum, sodium-potassium alloy, lithium-aluminum alloy, magnesium-silver. Examples include alloys, indium, rare earth metals (ytterbium, etc.). These may be used alone, but in order to achieve both stability and electron injection properties, it is preferable to use two or more in combination. Among these materials, alkali metals and alkaline earth metals are preferable from the viewpoint of electron injecting property, and materials mainly composed of aluminum are preferable from the viewpoint of storage stability. Here, the material mainly composed of aluminum is not only aluminum alone but also an alloy or a mixture of aluminum and 0.01 to 10% by mass of alkali metal or alkaline earth metal (lithium-aluminum alloy, magnesium-aluminum alloy, etc. ).
[0100]
When the cathode is a transparent cathode and light is extracted from the cathode side, it should be substantially transparent to light. Specifically, the transmittance is preferably 60% or more, and more preferably 70% or more. In order to achieve both electron injection and transparency, a two-layer structure of a thin film layer made of the above metal and a transparent conductive layer can be taken. The material of the metal thin film layer is described in detail in JP-A-2-15595 and JP-A-5-121172. The thickness of the metal thin film layer is preferably 1 nm or more and 50 nm or less. When the thickness of the metal thin film layer is 1 nm or less, it is difficult to form the thin film layer uniformly. On the other hand, when it is thicker than 50 nm, the transparency is deteriorated.
[0101]
The material used for the transparent conductive layer in the case of the two-layer structure is not particularly limited as long as it is a material having conductivity and semiconductivity and being transparent. The materials listed as examples of the anode in the above (a) can be suitably used. Among them, for example, tin oxide doped with antimony or fluorine (ATO, FTO), tin oxide, zinc oxide, indium oxide, indium tin oxide ( ITO), indium zinc oxide (IZO), and the like. The thickness of the transparent cathode is preferably 30 nm or more and 500 nm or less. When the thickness of the transparent cathode is less than 30 nm, the conductivity and semiconductivity are poor, and when it is more than 500 nm, the productivity is poor.
[0102]
There is no restriction | limiting in particular in the formation method of a cathode, Although it can carry out according to a well-known method, in this invention, it is preferable to carry out in a vacuum apparatus. The cathode can be formed by a wet method such as a printing method or a coating method, a physical method such as a vacuum deposition method, a sputtering method or an ion plating method, or a chemical method such as a CVD method or a plasma CVD method. The formation method may be appropriately selected in consideration of suitability with the cathode material. For example, when two or more metals are used as the cathode material, the materials can be formed by sputtering simultaneously or sequentially. When an organic conductive material is used, a wet film forming method may be used. The patterning of the cathode can be performed in the same manner as the transparent conductive layer.
[0103]
A dielectric layer made of an alkali metal or alkaline earth metal fluoride or the like may be inserted between the cathode and the organic electroluminescent layer with a thickness of 0.1 to 5 nm. The dielectric layer can be formed by, for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like.
[0104]
(4) Organic electroluminescent layer (electroluminescence layer)
Since the organic layer constituting the organic electroluminescent layer and the method for forming the organic layer are as described in [2] and (3) above, description thereof is omitted.
[0105]
(5) Other layers
As a layer constituting the organic electroluminescent element, it is preferable to provide a protective layer or a sealing layer in order to prevent deterioration of light emitting performance. Furthermore, in the transfer material, if the light emitting performance is not affected, a release layer may be provided between the plate and the organic layer in order to improve transferability, or an adhesive layer may be provided between the organic layer and the deposition surface. .
[0106]
(A) Protective layer
The organic electroluminescent device may have a protective layer described in JP-A-7-85974, 7-192866, 8-22891, 10-275682, 10-106746, and the like. The protective layer is formed on the uppermost surface of the organic electroluminescent element. Here, the top surface refers to the outer surface of the back electrode when, for example, the substrate support, the transparent conductive layer, the organic compound layer, and the back electrode are laminated in this order, and for example, the substrate support, the back electrode, and the organic compound layer. When the transparent conductive layer is laminated in this order, it refers to the outer surface of the transparent conductive layer. The shape, size, thickness and the like of the protective layer are not particularly limited. The material of the protective layer is not particularly limited as long as it has a function of suppressing intrusion or permeation of an element that can deteriorate the organic electroluminescent element such as moisture or oxygen into the element. Silicon oxide, silicon dioxide, germanium monoxide, germanium dioxide and the like can be used.
[0107]
The method for forming the protective layer is not particularly limited. For example, vacuum deposition method, sputtering method, reactive sputtering method, molecular send epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, plasma CVD method, laser CVD. A method, a thermal CVD method, a coating method, or the like can be applied.
[0108]
(B) Sealing layer
The organic electroluminescent element is preferably provided with a sealing layer for preventing intrusion of moisture and oxygen. As a material for forming the sealing layer, a copolymer of tetrafluoroethylene and at least one comonomer, a fluorinated copolymer having a cyclic structure in the copolymer main chain, polyethylene, polypropylene, polymethyl methacrylate, polyimide, Polyurea, polytetrafluoroethylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, chlorotrifluoroethylene or a copolymer of dichlorodifluoroethylene and another comonomer, a water-absorbing substance having a water absorption of 1% or more, a water absorption of 0. 1% or less of moisture-proof substance, metal (In, Sn, Pb, Au, Cu, Ag, Al, Ti, Ni, etc.), metal oxide (MgO, SiO, SiO)₂, Al₂O₃, GeO, NiO, CaO, BaO, Fe₂O₃, Y₂O₃TiO₂Etc.), metal fluoride (MgF)₂, LiF, AlF₃, CaF₂Etc.), liquid fluorinated carbon (perfluoroalkane, perfluoroamine, perfluoroether, etc.), and liquid fluorinated carbon in which an adsorbent of moisture or oxygen is dispersed.
[0109]
In order to block moisture and oxygen from the outside, it is preferable to seal the organic compound layer with a sealing member such as a sealing plate or a sealing container. Even if it installs a sealing member only in the back electrode side, you may cover the whole light emitting laminated body with a sealing member. The shape, size, thickness, and the like of the sealing member are not particularly limited as long as the organic compound layer can be sealed and external air can be blocked. As a material used for the sealing member, glass, stainless steel, metal (aluminum, etc.), plastic (polychlorotrifluoroethylene, polyester, polycarbonate, etc.), ceramic, or the like can be used.
[0110]
When installing the sealing member on the light emitting laminate, a sealing agent (adhesive) may be used as appropriate. When covering the whole light emitting laminated body with a sealing member, you may heat-seal sealing members without using a sealing agent. As the sealant, an ultraviolet curable resin, a thermosetting resin, a two-component curable resin, or the like can be used.
[0111]
Further, a water absorbent or an inert liquid may be inserted into the space between the sealing container and the organic electroluminescent element. The moisture absorbent is not particularly limited, and specific examples include barium oxide, sodium oxide, potassium oxide, calcium oxide, sodium sulfate, calcium sulfate, magnesium sulfate, phosphorus pentoxide, calcium chloride, magnesium chloride, copper chloride, cesium fluoride. , Niobium fluoride, calcium bromide, vanadium bromide, molecular sieve, zeolite, magnesium oxide and the like. As the inert liquid, paraffins, liquid paraffins, fluorinated solvents (perfluoroalkane, perfluoroamine, perfluoroether, etc.), chlorinated solvents, silicone oils and the like can be used.
[0112]
The light-emitting element of the present invention can emit light by applying a direct current (which may contain an alternating current component if necessary) voltage (usually 2 to 40 V) or a direct current between the anode and the cathode. . Regarding the driving of the light emitting device of the present invention, JP-A-2-148687, JP-A-6-301355, JP-A-5-29080, JP-A-7-134558, JP-A-8-234485, JP-A-8-2441047, US Pat. No. 5,828,429. No. 6023308, Japanese Patent No. 2784615, etc. can be used.
[0113]
【Example】
The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
[0114]
Example 1 16(Example of organic layer formation on the plate by vacuum film formation)
(A) Plate production
Square area (length of one side) in the center of a 0.5 mm (thickness) × 5 cm × 5 cm quartz glass plate [thermal expansion coefficient: 0.8 ppm / ° C. (TMA measurement, 10 ° C./min)] 5 μm (height) × 100 μm by a photolithography method (a mask is formed on a portion where a pattern portion of a quartz glass plate is formed and a non-pattern portion is removed by etching). A plate having a pattern portion in which convex portions of 50 μm were provided at intervals of 25 μm was produced.
[0115]
(B) Fabrication of substrate
In accordance with the materials and procedures shown in Table 1, nine types of substrates [2.5 cm (vertical) × 2.5 cm (horizontal)] for use as the first substrate or the second substrate were prepared. The obtained substrate No. About 101-109, the thermal linear expansion coefficient was measured. The results are shown in Table 1.
[0116]
[Table 1]

Note: (1) Measured by TMA method (heating rate: 10 ° C./min).
[0117]
(C) Preparation of transfer material
On each plate produced in (A) above, tris (2-phenylpyridyl) iridium complex [phosphorescent material (orthometal complex)] and 4,4′-N, N′-dicarbazole biphenyl were formed by vacuum evaporation. (Host material) was co-evaporated at a rate of 0.1 nm / second and 1 nm / second, respectively, to form a light-emitting organic layer having a thickness of 40 nm, thereby preparing a transfer material.
[0118]
(D) Production of laminate D (substrate / cathode)
Among the substrates shown in Table 1, No. 101, 104, and 108 are put in a cleaning container and cleaned with isopropyl alcohol (IPA). Then, a mask is set so that the light emitting area becomes 5 mm × 5 mm, and Al is formed with a film thickness of 250 nm by vapor deposition. The cathode was formed by filming. An aluminum lead wire was connected from the cathode, and the laminate No. D101, D104 and D108 were obtained.
[0119]
(E) Production of laminate E (substrate / cathode / organic layer)
In the same manner as (D) above, no. A cathode was formed by depositing Al with a film thickness of 250 nm by vapor deposition on 103, 104, 105, 106, 108, and 109, and a substrate with a cathode was produced. Next, on the cathode, the following structural formula (1):
[Chemical 1]

The deposition rate of each material is adjusted so that the LiF content is 10% by weight with respect to the electron transporting organic material having the structure represented by the above, and the mixed layer is laminated with a film thickness of 36 nm. Produced. Further, an aluminum lead wire was connected from the Al cathode, and the laminate No. E103, E104, E105, E106, E108 and E109 were produced.
[0120]
(F) Production of laminate F (substrate / anode)
Among the substrates shown in Table 1, No. 101, 102, 106, 108 and 109 are introduced into the vacuum chamber and SnO is introduced.₂Using an ITO target [indium: tin = 95: 5 (molar ratio)] having a content of 10% by mass, DC magnetron sputtering (substrate temperature: 250 ° C., oxygen pressure: 1 × 10^-3  Pa), a transparent electrode made of an ITO thin film having a thickness of 0.2 μm was formed. The surface resistance of the ITO thin film was measured and found to be 10Ω / □. Aluminum lead wires were connected from the transparent electrode (ITO) to form a laminate. Each substrate on which the transparent electrode was formed was put in a cleaning container, washed with isopropyl alcohol (IPA), and then subjected to oxygen plasma treatment to obtain a laminate No. 1. F101, F102, F106, F108 and F109 were produced.
[0121]
(G) Production of laminate G (substrate / anode / organic layer)
In the same manner as (F) above, no. A transparent electrode made of an ITO thin film having a thickness of 0.2 μm was formed on 101, 102, 106, 107 and 109, and an aluminum lead wire was connected to the transparent electrode (ITO) to produce a laminate. Each substrate on which the transparent electrode was formed was placed in a cleaning container, cleaned with isopropyl alcohol (IPA), and then subjected to oxygen plasma treatment. After spin-coating an aqueous dispersion of polyethylene dioxythiophene / polystyrene sulfonic acid (manufactured by BAYER, trade name: Baytron P, solid content: 1.3% by mass) on the surface of the treated transparent electrode, the surface is treated at 150 ° C. for 2 hours. By vacuum-drying to form a 100 nm thick hole transporting organic layer, the laminate No. G101, G102, G106, G107 and G109 were produced.
[0122]
(H) Formation of organic layer by peeling transfer method
Laminate No. produced in (D) above. D101, D104, and D108, and the laminate No. 1 prepared in (E) above. E103, E105, E108, and E109, and the laminate No. 1 prepared in (F) above. F102 and F106, and the laminates No. 1 prepared in (G) above. The luminescent organic layer of the transfer material prepared in (C) was transferred to G102, G107, and G109. Both layers are stacked such that the light emitting organic layer side of the transfer material faces the deposition surface (the surface having the cathode, anode, electron transporting organic thin film or hole transporting organic thin film) of each laminate, It was installed between a pair of hot plates with a pressing force of MPa (both hot plates having a temperature adjusted to 110 ° C.), and a heat treatment and a pressure treatment for 30 seconds were performed simultaneously. Next, the plate is peeled off to form a light-emitting organic layer on the film formation surface of each laminate, so that the laminate H (No. HD101, HD104, HD108, HE103, HE105, HE108, HE109, HF102, HF106, HG101, HG102, HG107 and HG109) were produced.
[0123]
(I) Device fabrication
Among the laminates H produced in (H) above, No. HD101, HD104, HD108, HE103, HE105, HE108, HE109, HF102, HF106, HG102, HG107 and HG109 were used as the first substrate (first substrate) side laminate, and the laminate No. produced in (D) above. . D108 and the laminate No. produced in the above (E). E103, E104, E106, and E108, and the laminate No. 1 prepared in (F) above. F101, F102, F108, and F109, and the laminates No. 1 prepared in (G) above. G101, G102, G106, and G109, and the laminate No. 1 manufactured in (H) above. HG101 is used as a second substrate (second substrate) side laminate, and each first substrate side laminate and each second substrate side laminate are bonded together in the combinations shown in Table 4, thereby organic EL. An element was produced. The two substrates are laminated together with the light emitting organic layer side of the first substrate side laminate and the film formation surface of the second substrate side laminate (cathode, anode, electron transporting organic thin film, hole transporting organic thin film or light emitting property). Both are stacked so that the surface having the organic layer faces each other, and a gap between a pair of rollers with a pressure of 0.3 MPa (both heated rollers whose temperature is adjusted to 160 ° C.) is 0.1 m / min. This was done by passing at speed. The combination of each first substrate-side laminate and each second substrate-side laminate shown in Table 4 has a configuration in which the obtained organic EL element has a cathode and an anode, and light emission can be extracted from at least one side thereof. It was made to become.
[0124]
(J) Evaluation
The light emitting property of the organic EL device produced in the above (I) was evaluated. When a DC voltage was applied to the organic EL elements using Keithley Instruments Co., Ltd. Source Measure Unit 2400, sufficient light emission was detected with a drive current of 2 mA, and the bonding was good. there were.
[0125]
About the laminated body H produced by said (H), pixel position accuracy was evaluated. A method for evaluating pixel position accuracy will be described. First, five laminates H (No. HD101, HD104, HD108, HE103, HE105, HE108, HE109, HF102, HF106, HG101, HG102, HG107, and HG109) are produced, and the luminescent organic layer of each laminate H is prepared. A micrograph of a square region of 5000 μm × 5000 μm was taken on the surface provided with. At this time, the lower left vertex of the square area was regarded as the origin of the XY coordinates, and the left vertical side of the square area was regarded as being coincident with the Y axis. Images were taken with their positions aligned so that the lower left vertex of one reference pixel (hereinafter referred to as “reference pixel”) coincides with the origin of the XY coordinates and the left vertical side of the reference pixel coincides with the Y axis. If the light emitting organic layer is ideally transferred, the vertical side length of each arranged pixel is 50 μm, and the pixel interval is 25 μm. Therefore, the upper left vertex of the square area [coordinates (0, 5000 μm). ) And the upper left vertex (hereinafter referred to as “measurement point”) of the 67th pixel along the Y-axis direction from the origin. Therefore, the upper left apex [point of coordinates (0, 5000 μm)] of the square area was regarded as an ideal point, and the deviation from the ideal point was examined with respect to the measurement point of each micrograph. The deviation from the ideal point of the measurement point is the length between the origin of the XY coordinates and the ideal point (5000 μm), that is, the length of one side of the square area is the reference length, and the length between the origin and the measurement point is measured. The difference between the value and the reference length is obtained. No. The measurement results of 5 points were averaged for each of the organic EL elements 1 to 17. Evaluation criteria for pixel position accuracy are as follows. The results are shown in Table 4.
A: Deviation from the ideal point was less than 0.1% (less than 5 μm).
○: Deviation from the ideal point was less than 0.5% (less than 25 μm).
X: The deviation from the ideal point was 0.5% or more (25 μm or more).
[0126]
When the deviation from the ideal point is 0.5% or more, there is a problem that when the organic EL element is aligned with the drive circuit, the position of the drive circuit and the pixel cannot be aligned. In addition, when a plurality of light-emitting organic layers are provided with different colors (for example, three colors), there arises a problem that pixels overlap.
[0127]
Comparative Example 1
White plate glass (0.5 mm × 2.5 cm × 2.5 cm) was introduced into the vacuum chamber and SnO₂Using an ITO target [indium: tin = 95: 5 (molar ratio)] having a content of 10% by mass, DC magnetron sputtering (substrate temperature: 250 ° C., oxygen pressure: 1 × 10^-3  Pa), a transparent electrode made of an ITO thin film having a thickness of 0.2 μm was formed. The surface resistance of the ITO thin film was measured and found to be 10Ω / □. After connecting the aluminum lead wire from the transparent electrode (ITO), the white plate glass plate on which the transparent electrode was formed was put into a cleaning container, washed with isopropyl alcohol (IPA), and then subjected to oxygen plasma treatment. After spin-coating an aqueous dispersion of polyethylene dioxythiophene / polystyrene sulfonic acid (BAYER, trade name: Baytron P, solid content: 1.3% by mass) on the surface of the transparent electrode subjected to the oxygen plasma treatment, 150 The film was vacuum-dried at 2 ° C. for 2 hours to form a hole transporting organic layer having a thickness of 100 nm. Next, a light emitting organic layer coating solution having the composition shown in Table 2 was applied onto the hole transporting organic layer at a rate of 10 m / min using a gravure printing machine and dried at 80 ° C. A light emitting organic layer having a pixel pattern in which convex pixel portions of nm (thickness) × 100 μm × 50 μm were provided at intervals of 25 μm was formed.
[0128]
[Table 2]

[0129]
Furthermore, on the luminescent organic layer, polyvinyl butyral (Mw = 50000, manufactured by Aldrich), the following structural formula (2):
[Chemical 2]

A coating liquid for an electron transporting organic layer containing an electron transporting compound represented by formula (1) and 1-butanol is applied at a rate of 10 m / min using an extrusion coater and dried at 80 ° C. An electron transporting organic layer having a thickness of 36 nm was formed. Table 3 shows the composition of the electron transporting organic layer coating solution.
[0130]
[Table 3]

[0131]
Finally, Al was formed into a film having a thickness of 250 nm by a vapor deposition method (cathode). Further, an aluminum lead wire was connected from the Al cathode to produce an organic EL element. About the obtained organic EL element, it carried out similarly to Examples 1-16, and evaluated pixel position accuracy. The results are shown in Table 4.
[0132]
[Table 4]

Note: (1) WG represents white plate glass, SG represents quartz glass, PI represents a polyimide sheet, Al represents an aluminum foil, UV represents an ultraviolet curable resin layer, PVC represents a hard polyvinyl chloride sheet. TH represents a thermosetting resin layer, PET represents a polyethylene terephthalate sheet, PES represents a polyethersulfone sheet, IN represents a cathode, Y represents an anode, EL represents a luminescent organic layer, TL Represents an organic layer other than the light-emitting organic layer, and // represents a bonding position.
(2) Since the pixel was blurred, it was calculated from an approximate boundary surface.
[0133]
As can be seen from Table 4, in Examples 1 to 16, it was found that organic electroluminescent elements having excellent pixel position accuracy can be obtained easily. On the other hand, in Comparative Example 1, since the transfer was not performed, the pixel position accuracy was inferior. Moreover, since Examples 1-16 were produced from both electrode sides, they were produced with good productivity as compared with Comparative Example 1 laminated from one side.
[0134]
Example 17 ~ 32(Example of forming an organic layer on the plate by coating)
Organic EL elements (Nos. 18 to 33) were produced in the same manner as in Examples 1 to 16, except that the transfer material was changed as follows. The transfer material was coated in the same manner as in Examples 1 to 16 with a light emitting organic layer coating solution having the composition shown in Table 5 by a bar coater, and dried at room temperature to obtain a thickness of 40 nm. The light emitting organic layer was formed. A laminate produced using this transfer material was designated as a laminate H ′.
[0135]
[Table 5]

[0136]
About the obtained organic EL element (No. 18-33), it carried out similarly to Examples 1-16, and evaluated luminous property. As a result, all the organic EL elements detected sufficient light emission at a driving current of 2 mA, and the bonding was good.
[0137]
Table 6 shows the results of evaluating the pixel position accuracy of the stacked body H ′ in the same manner as in Examples 1 to 16.
[0138]
[Table 6]

Note: (1) Same as Table 4
[0139]
As is clear from Table 6, it was found that in Examples 17 to 32, organic electroluminescent elements having excellent pixel position accuracy can be obtained easily.
[0140]
Example 33 ~ 42
Except having changed the laminated body G as follows, the organic EL element (No. 34-43) was produced similarly to Examples 1-16. The laminated body G is No. 1 among the substrates shown in Table 1 in the same manner as in Examples 1-16. A transparent electrode made of an ITO thin film having a thickness of 0.2 μm was formed on 101, 102, 106, 107 and 109, and aluminum lead wires were connected to the transparent electrode (ITO). Each substrate on which the transparent electrode was formed was placed in a cleaning container, cleaned with isopropyl alcohol (IPA), and then subjected to oxygen plasma treatment. On the surface of the treated transparent electrode, the following structural formula (3):
[Chemical 3]

A polymer compound (Et-PTPDK) represented by the following structural formula (4):
[Formula 4]

A hole transporting organic layer coating solution containing an additive (TBPA) represented by the formula (II) and dichloroethane is applied using an extrusion-type coating machine and dried at room temperature, whereby a hole transporting property having a thickness of 40 nm is obtained. An organic layer was formed. Table 7 shows the composition ratio of the coating liquid for hole transporting organic layer. The obtained laminated body was designated as a laminated body G ′. A laminate obtained by transferring the light emitting organic layer to the laminate G ′ was designated as a laminate HG ′.
[0141]
[Table 7]

[0142]
About the obtained organic EL element (No. 34-43), it carried out similarly to Examples 1-16, and evaluated luminous property. As a result, all the organic EL elements detected sufficient light emission at a driving current of 2 mA, and the bonding was good.
[0143]
Table 8 shows the results of evaluating the pixel position accuracy of the stacked body HG ′ in the same manner as in Examples 1 to 16.
[0144]
[Table 8]

Note: (1) Same as Table 4
[0145]
As is apparent from Table 8, it was found that in Examples 33 to 42, an organic electroluminescent element excellent in pixel position accuracy can be easily obtained.
[0146]
Example 43 ~ 58
Organic EL elements (Nos. 44 to 59) were produced in the same manner as in Examples 1 to 16, except that the transfer material was changed as described below. The transfer material was a square area (length of one side) of a central portion of a stainless steel plate [thermal expansion coefficient: 12 ppm / ° C. (TMA measurement, 10 ° C./min)] of 2 cm (thickness) × 5 cm × 5 cm. : 20 mm), 5 μm (height) × 100 μm × 50 μm by a photolithography method (a mask is formed on a portion where a pattern portion of a stainless steel plate is formed, and a non-pattern portion is removed by etching). A plate having a pattern portion having protrusions of 25 μm was prepared, and a light emitting organic layer was formed thereon in the same manner as in Examples 1-16. A laminate produced using this transfer material was designated as a laminate H ″.
[0147]
About the obtained organic EL element (No. 44-59), it carried out similarly to Examples 1-16, and evaluated luminous property. As a result, in any organic EL element, sufficient light emission was detected with a driving current of 2 mA, and the bonding was good.
[0148]
Table 9 shows the results of evaluating the pixel position accuracy of the stacked body H ″ in the same manner as in Examples 1 to 16.
[0149]
[Table 9]

Note: (1) Same as Table 4
[0150]
As is clear from Table 9, in Examples 43 to 58, it was found that an organic electroluminescent element having excellent pixel position accuracy can be easily obtained.
[0151]
【The invention's effect】
As described above in detail, by providing an organic layer on a plate having a predetermined pattern portion and transferring the organic layer to the substrate, a patterned organic layer can be easily formed on the substrate, and the organic layer It is possible to provide a method for producing an organic electroluminescent device excellent in film thickness uniformity, light emission efficiency, light emission amount uniformity and durability at low cost.
[0152]
Since the plate is excellent in mechanical strength and stability, the positional accuracy when the organic layer is transferred is good. By using the plate, high-definition and high-precision patterns (pixels and the like) can be easily manufactured with high productivity. Furthermore, it can be used repeatedly by washing / drying the plate after transferring the organic layer. In the case of using a plate, an organic layer may be formed at least in the pattern portion. For this reason, the manufacture of an organic electroluminescent device using a plate has advantages such as less waste, low cost, and no need for special manufacturing equipment.
[0153]
The organic electroluminescent element obtained by the production method of the present invention is suitable for a full color display, a backlight of a liquid crystal display element, a surface light source for illumination, a light source array of a printer, and the like.
[Brief description of the drawings]
FIG. 1 is a (schematic) cross-sectional view showing an example of a relief plate provided with an organic layer in a pattern portion.
FIG. 2 is a plan view of the letterpress of FIG.
FIG. 3 is a (schematic) cross-sectional view showing an example of a relief plate in which an organic layer is provided in a pattern portion and a non-pattern portion.
FIG. 4 is a (schematic) cross-sectional view showing an example of an intaglio in which an organic layer is provided in a pattern portion.
FIG. 5 is a plan view of the intaglio shown in FIG.
FIG. 6 is a (schematic) cross-sectional view showing an example of an intaglio in which an organic layer is provided in a pattern part and a non-pattern part.
FIG. 7 is a (schematic) cross-sectional view showing an example of a lithographic plate provided with an organic layer.
FIG. 8 is a plan view of the intaglio plate of FIG. 7;
FIG. 9 is a (schematic) cross-sectional view showing an example of a lithographic plate coated with an organic layer coating solution.
[Explanation of symbols]
1 ... version
11 ... convex part
12 ... recess
2. Pattern part
3. Non-pattern part
4 ... Organic layer
4 '... coating solution for organic layer

Claims (7)

Using a plate having at least one organic layer in at least the pattern portion, the plate and the first substrate so that the organic layer side of the plate faces the electrode side of the first substrate having at least an electrode And then subjecting the plate to peeling off the plate, and then transferring the organic layer to the electrode side of the first substrate. An organic electroluminescent device comprising a method of bonding the first substrate having at least one organic layer and the second substrate having at least an electrode after the step of transferring the organic layer. Manufacturing method. The manufacturing method according to claim 1, further comprising a step of further transferring at least one organic layer on the organic layer provided on the first substrate after the step of transferring the organic layer. The manufacturing method according to claim 1, wherein the plate is a relief plate. The said organic layer contains a luminescent organic compound or a carrier transportable organic compound at least, The manufacturing method as described in any one of Claims 1-3 characterized by the above-mentioned. The manufacturing method according to any one of claims 1 to 4, wherein a thermal expansion coefficient of at least one of the first substrate and the second substrate is 20 ppm / ° C or less. An organic electroluminescent device manufactured by the manufacturing method according to claim 1. An electrode, at least one organic layer including a light-emitting organic layer, a second electrode, and a second substrate are provided in this order on at least one of the first substrate and the second substrate. The organic electroluminescent element according to claim 6, wherein one of the electrodes is transparent, and an electrode of the transparent substrate is transparent.

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