JP3684043B2 - Electrophotographic photoreceptor, process cartridge and electrophotographic apparatus having the electrophotographic photoreceptor - Google Patents

Description

式中、Ｒ_１、Ｒ_２、Ｒ_３およびＲ_４は水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基、−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化５】

以上は−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化６】

であり、Ｒ_５およびＲ_６はニトロ基を有する芳香環基またはニトロ基を有する複素環基を示し、Ｒ_７はアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基または置換基を有してもよい複素環基を示し、ｐおよびｑは０、１、２のいずれかの整数、ｒは０、１のいずれかの整数であり、Ｒ_６およびＲ_７は互いに直接または飽和炭化水素、不飽和炭化水素、酸素原子、硫黄原子を介して結合して環を形成してもよい。
【００１２】
また本発明の参考の一態様に係る単層型電子写真感光体は、導電性支持体上に直接または下引き層を介して単層の感光層を設けてなり、その感光層は少なくとも電荷発生物質、有機正孔輸送物質および有機電子輸送物質が結着樹脂中に分散され、かつ、該有機電子輸送物質が下記一般式（２）で示される化合物である：
【化７】

式中、Ｒ_１、Ｒ_２、Ｒ_３およびＲ_４は水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基、−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化８】

以上は−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化９】

であり、Ｒ_５およびＲ_６はニトロ基を有する芳香環基またはニトロ基を有する複素環基を示し、Ｒ_７はアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基または置換基を有してもよい複素環基を示し、ｐおよびｑは０、１、２のいずれかの整数、ｒは０、１のいずれかの整数であり、Ｒ_６およびＲ_７は互いに直接または飽和炭化水素、不飽和炭化水素、酸素原子、硫黄原子を介して結合して環を形成してもよい。
【００１３】
本発明は、導電性支持体上に直接または下引き層を介して単層の感光層を設けてなり、その感光層は少なくとも電荷発生物質、有機正孔輸送物質および有機電子輸送物質が結着樹脂中に分散され、かつ、該有機電子輸送物質が下記一般式（３）で示される化合物であることを特徴とする単層型電子写真感光体から構成される：
一般式（３）
【化１０】

式中、Ｒ_１、Ｒ_２、Ｒ_３およびＲ_４は水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基、−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化１１】

を示し、Ｒ_１〜Ｒ_４のうち少なくとも２つ以上は−（ＣＨ＝ＣＨ）ｐ−ＮＯ_２、−（ＣＨ＝ＣＨ）ｑ−Ｒ_５または
【化１２】

であり、Ｒ_５およびＲ_６はニトロ基を有する芳香環基またはニトロ基を有する複素環基を示し、Ｒ_７はアルキル基、置換基を有してもよいアラルキル基、置換基を有してもよい芳香環基または置換基を有してもよい複素環基を示し、ｐおよびｑは０、１、２のいずれかの整数、ｒは０、１のいずれかの整数であり、Ｒ_６およびＲ_７は互いに直接または飽和炭化水素、不飽和炭化水素、酸素原子、硫黄原子を介して結合して環を形成してもよい。
【００１４】
また、本発明は前記本発明の単層型電子写真感光体、及び帯電手段、現像手段及びクリ−ニング手段からなる群より選ばれる少なくとも一つの手段を一体に支持し、電子写真装置本体に着脱自在であることを特徴とするプロセスカ−トリッジから構成される。
【００１５】
また、本発明は前記本発明の単層型電子写真感光体、帯電手段、像露光手段、現像手段及び転写手段を有することを特徴とする電子写真装置から構成される。
【００１６】
【発明の実施の形態】
本発明の単層型電子写真感光体は帯電性と感度に優れ、低速から高速までの電子写真プロセスに好適であり、また電荷発生物質の選択により、分光感度域が制御でき、白黒またはフルカラ−用の複写機から書き込み用にＬＥＤやレ−ザ−を用いたペ−ジプリンタ−の感光体にまで適用することが可能である。
【００１７】
従来の電荷発生物質を樹脂に分散させた形態の単層型電子写真感光体では電荷発生物質が電荷輸送機能も兼ねており、かつ、正孔及び電子の両方の輸送性の良好な電荷発生物質がないため、感度が低い。電荷の輸送性が低いために繰り返し使用時に残留電位の上昇や帯電電位の低下が起こる等の欠点があった。これらの欠点を解決するために電荷発生物質と正孔輸送物質を樹脂中に分散した感光体も提案されたが、単に正孔輸送物質を添加した感光体では、正孔輸送機能は向上するが電子輸送は引き続き電荷発生物質が担っているために十分ではなく、残留電位が高い、繰り返し使用時の電位安定性が低い等の問題点を解決できなかった。
【００１８】
本発明においては、その感光層に少なくとも電荷発生物質、有機正孔輸送物質及び有機電子輸送物質が結着樹脂中に分散され、かつ該有機電子輸送物質が一般式（３）で示される化合物を用いることにより、上記問題点を解決するものである。これらの問題点が解決される理由は完全には明らかではないが、一つには一般式（３）で示される化合物の分子内における電子軌道の共役が広範囲に広がっているために電子輸送性が優れていること、更には一般式（３）で示される化合物の非結合準位のエネルギーレベルが低いために電荷発生物質から一般式（３）で示される化合物への電子の注入性が高いこと等によって、電荷発生物質内の光吸収によって発生した電子及び正孔が一般式（３）で示される化合物及び有機正孔輸送物質に容易に注入、輸送されることに起因するものと考えられる。
【００１９】
本発明の単層型電子写真感光体を図面に沿って更に詳細に説明する。図１は本発明の単層型電子写真感光体の１例を示しており、１Ａは導電性支持体、１Ｂは感光層、１Ｂ１は電荷発生物質、１Ｂ２は結着樹脂中に有機正孔輸送物質と有機電子輸送物質（一般式（３）で示される化合物）とが分子状に分散されたマトリックスを表わしている。
【００２０】
本発明の感光体においては前述したように一般式（３）で示される化合物が有機電子輸送物質として添加される。
【００２１】
次に、本発明の参考例に係る電子写真感光体の感光層に用いられる一般式（１）及び一般式（２）で示される化合物、及び本発明に係る電子写真感光体の感光層に用いられる一般式（３）で示される化合物の代表例を列挙する。ただし、これらの化合物に限定されるものではない。
【００２２】
【表１】

【表２】

【表３】

【表４】

【表５】

【表６】

【００２３】
【表７】

【表８】

【表９】

【表１０】

【表１１】

【表１２】

【００２４】
【表１３】

【表１４】

【表１５】

【表１６】

【表１７】

【表１８】

【表１９】

【００２５】
【表２０】

【表２１】

【表２２】

【表２３】

【表２４】

【００２６】
本発明における有機電子輸送物質（一般式（３）で示される化合物）の感光層１Ｂ全体に占める量は１〜５０ｗｔ％、好ましくは５〜４０ｗｔ％である。
【００２７】
本発明の感光体においては、必須成分として有機正孔輸送物質が含まれる。感光層中での有機正孔輸送物質の役割は電荷発生物質で発生した正孔を感光層中で移動させることである。この輸送機能により電荷発生物質中で正孔が蓄積されずに、電荷発生物質の電荷発生機能を十分に発揮させることができる。
【００２８】
本発明において用いられる有機正孔輸送物質としては、分子中にトリフェニルアミン部位を有する化合物、ヒドラゾン化合物、トリフェニルメタン化合物、ピラゾリン化合物、オキサジアゾ−ル化合物、カルバゾ−ル化合物、スチリル化合物、ブタジエン系化合物、ポリシラン化合物、ポリビニルカルバゾ−ル等のドナ−性化合物が挙げられる。有機正孔輸送物質の感光層１Ｂに占める割合は１５ｗｔ％以上、好ましくは２０〜５０ｗｔ％の範囲である。
【００２９】
感光層１Ｂにおける結着樹脂の役割は電荷発生物質の良好な分散と有機電子輸送物質及び有機正孔輸送物質の分子状の分散ばかりではなく、電子写真プロセスで必要とされる感光層の機械的強度も担っている。このため、結着樹脂の組成比が低い場合には、これらの諸特性が損なわれることとなる。従って、感光層に占める結着樹脂の量は極端に低くはできない。結着樹脂の感光層１Ｂ全体に占める割合は３０〜９０ｗｔ％、好ましくは４０〜７０ｗｔ％が適当である。
【００３０】
本発明において用いられる結着樹脂としては特に限定されるものではなく、市販の樹脂を使用することができる。感光層の結着樹脂として使用可能な樹脂の例としてはポリエステル樹脂、ポリカ−ボネ−ト樹脂、ポリスチレン樹脂、アクリル樹脂、フッ素樹脂、セルロ−ス、ポリウレタン樹脂、エポキシ樹脂、シリコ−ン樹脂、アルキド樹脂、塩化ビニル樹脂、塩化ビニル−酢酸ビニル共重合樹脂等が挙げられる。
【００３１】
本発明では電荷発生物質も感光層内の必須成分である。本発明において用いることのできる電荷発生物質としてはセレン化合物、アモルファスシリコン、硫化カドミウム、酸化亜鉛等の無機光導電性物質の粒子や、ビスアゾ顔料、トリスアゾ顔料、フタロシアニン顔料、ペリレン顔料、キナクリドン顔料、インジゴ顔料、多環キノン顔料等が挙げられる。これらの電荷発生物質の感光層１Ｂに含まれる量は０．１〜４０ｗｔ％、好ましくは０．３〜２０ｗｔ％の範囲が最適である。
【００３２】
本発明の感光層１Ｂの厚さは５〜１００μｍ、最適には７〜３５μｍの範囲である。
【００３３】
本発明で用いる導電性支持体１Ａとしてはアルミニウム、ニッケル、銅、ステンレス等の金属板、金属ドラムまたは金属箔、酸化スズ、ヨウ化銅等の薄膜を蒸着あるいは塗布したプラスチックフィルムあるいはガラス等が挙げられる。
【００３４】
本発明の感光体においては、導電性及び支持体と感光層の密着性の改良を目的として支持体と感光層との間に下引き層を設けることもできる。下引き層の材料としては前記感光層に用いる結着樹脂例に挙げた樹脂のほかに、ポリアミド樹脂、ポリビニルアルコ−ル、カゼイン、ポリビニルピロリドン等を用いることができる。下引き層の膜厚は０．０１〜２０μｍ、最適には０．１〜５μｍの範囲である。
【００３５】
更に本発明の感光体は感光層１Ｂの上に耐久性等の向上を目的として表面保護層を設けてもよい。
【００３６】
本発明の感光体の作成は、前記材料を有機溶媒中に溶解またはボ−ルミル、サンドミル、超音波等で分散して感光層形成液を調製し、これを浸漬法やブレ−ド塗布法、スプレ−塗布法等で導電性支持体１Ａ上に塗布し乾燥して感光層１Ｂを形成すればよい。
【００３７】
図２に本発明の電子写真感光体を有するプロセスカ−トリッジを有する電子写真装置の概略構成を示す。図において、１はドラム状の本発明の電子写真感光体であり、じく２を中心に矢印方向に所定の周速度で回転駆動される。感光体１は回転過程において、一次帯電手段３によりその周面に正または負の所定電位の均一帯電を受け、次いで、スリット露光やレ−ザ−ビ−ム走査露光等の像露光手段（不図示）からの画像露光光４を受ける。こうして感光体１の周面に静電潜像が順次形成されていく。
【００３８】
形成された静電潜像は、次いで現像手段５によりトナ−現像され、現像されたトナ−現像像は、不図示の給紙部から感光体１と転写手段６との間に感光体１の回転と同期取りされて給送された転写材７に、転写手段６により順次転写されていく。像転写を受けた転写材７は感光体面から分離されて像定着手段８へ導入されて像定着を受けることにより複写物（コピ−）として装置外へプリントアウトされる。像転写後の感光体１の表面は、クリ−ニング手段９によって転写残りトナ−の除去を受けて清浄面化され、更に前露光手段（不図示）からの前露光光１０により除電処理がされた後、繰り返し画像形成に使用される。なお、一次帯電手段３が帯電ロ−ラ−等を用いた接触帯電手段である場合は、前露光は必ずしも必要ではない。
【００３９】
本発明においては、上述の感光体１、一次帯電手段３、現像手段５及びクリ−ニング手段９等の構成要素のうち、複数のものをプロセスカ−トリッジとして一体に結合して構成し、このプロセスカ−トリッジを複写機やレ−ザ−ビ−ムプリンタ−等の電子写真装置本体に対して着脱可能に構成してもよい。例えば一次帯電手段３、現像手段５及びクリ−ニング手段９の少なくとも１つを感光体１と共に一体に支持してカ−トリッジ化し、装置本体のレ−ル１２等の案内手段を用いて装置本体に着脱可能なプロセスカ−トリッジ１１とすることができる。また、画像露光光４は、電子写真装置が複写機やプリンタ−である場合には、原稿からの反射光や透過光を用いる、あるいは、センサ−で原稿を読み取り、信号化し、この信号に従って行われるレ−ザ−ビ−ムの走査、ＬＥＤアレイの駆動及び液晶シャッタ−アレイの駆動等により照射される光である。
【００４０】
一方、ファクシミリのプリンタ−として使用する場合には、画像露光光４は受信デ−タをプリントするための露光光になる。図２はこの場合の１例をブロック図で示したものである。コントロ−ラ−１４は画像読取部１３とプリンタ−２２を制御する。コントロ−ラ−１４の全体はＣＰＵ２０により制御されている。画像読取部１３からの読取りデ−タは、送信回路１６を通して相手局に送信される。相手局から受けたデ−タは受信回路１５を通してプリンタ−２２に送られる。画像メモリには所定の画像デ−タが記憶される。プリンタ−コントロ−ラ−２１はプリンタ−２２を制御している。１７は電話である。回線１８から受信された画像（回線を介して接続されたリモ−ト端末からの画像情報）は、受信回路１５で復調された後、ＣＰＵ２０によって画像情報を複号処理され順次画像メモリ１９に格納される。そして、少なくとも１頁の画像が画像メモリ１９に格納されると、その頁の画像記録を行う。ＣＰＵ２０は、画像メモリ１９から１頁の画像情報を読み出し、プリンタ−コントロ−ラ−２１に複号化された１頁の画像情報を送出する。プリンタ−コントロ−ラ−２１は、ＣＰＵ２０からの１頁の画像情報を受け取ると、その頁の画像情報記録を行うべくプリンタ−２２を制御する。ＣＰＵ２０は、プリンタ−２２による記録中に、次ぎの頁の受信を行っている。このようにして、画像の受信と記録が行われる。
【００４１】
【実施例】
参考例１
オキシチタニルフタロシアニン４ｇをポリビニルブチラ−ル（ブチラ−ル化度６５％、重量平均分子量３５０００）７ｇをシクロヘキサノン溶媒８５ｇに溶解した液と共にサンドミルで４８時間分散した。
【００４２】
化合物例（１）の有機電子輸送物質５ｇ、下記構造式（ａ）の有機正孔輸送物質４ｇ
【化７】

及びＺ型ポリカ−ボネ−ト樹脂（重量平均分子量３００００）９ｇをクロルベンゼン７０ｇに溶解した液に、先に調製したオキシチタニルフタロシアニンの分散液５ｇを加え、更にボ−ルミルで１時間分散して感光層用の塗工液を調製した。
【００４３】
次に、アルミニウム基板上にポリアミド樹脂（商品名アミランＣＭ−８０００、東レ（株）製）の５％メタノ−ル溶液をマイヤ−バ−で塗布し０．５μｍの下引き層を形成した上に、更にマイヤ−バ−で先に調製した感光層塗工液を塗布し、乾燥後の膜厚が１６μｍの単層型電子写真感光体を作成した。
【００４４】
この電子写真感光体を川口電機（株）製静電複写紙試験装置（ＥＰＡ−８１００）を用い±６ＫＶの印加電圧を加え、その表面電位を正または負に帯電させて初期の表面電位Ｖａ（Ｖ）、３秒間暗減衰させた後の表面電位Ｖｄ（Ｖ）と２０ｌｕｘの光源で光照射して表面電位が１／２に減衰するのに要する露光量Ｅ_1/2 （ｌｕｘ・ｓｅｃ）を測定した。
【００４５】
また、得られた感光体シ−トをアルミニウム製シリンダ−上に貼り付けた後、複写機ＮＰ−６０６０（キヤノン（株）製）の改造機に装着し、表面電位：Ｖｄ＝＋６５０Ｖ、露光後電位：Ｖｌ＝＋２００Ｖになるように設定した後、１０００回複写を繰り返し行い、その後の表面電位：Ｖｄ’及び露光後電位：Ｖｌ’を表面電位計を用いて測定した。更に１０００回複写後の表面電位の変動分：ΔＶｄ＝Ｖｄ−Ｖｄ’及び露光後電位の変動分：ΔＶｌ＝Ｖｌ−Ｖｌ’を算出し、結果を表２５に示す。
【００４６】
参考例２〜１０
参考例１で用いた有機正孔輸送物質、有機電子輸送物質を表２５に示すように代えた他は、参考例１と同様にして電子写真感光体を作成し同様の評価を行った。結果を表２５に示す。
【００４７】
使用した有機正孔輸送物質は下記構造式（ｂ）〜（ｉ）の化合物である。
構造式（ｂ）
【化８】

構造式（ｃ）
【化９】

構造式（ｄ）
【化１０】

構造式（ｅ）
【化１１】

構造式（ｆ）
【化１２】

構造式（ｇ）
【化１３】

構造式（ｈ）
【化１４】

構造式（ｉ）
【化１５】

【００４８】
比較例１
参考例１において、有機電子輸送物質を除いた他は、参考例１と同様の条件で電子写真感光体を作成し、同様の評価を行った。結果を表２５に示す。
【００４９】
比較例２及び３
参考例１において用いた有機電子輸送物質に代えて下記構造式（ｊ）及び（ｋ）を用いた他は、参考例１と同様にして電子写真感光体を作成し、同様の評価を行った。結果を表２５に示す。
構造式（ｊ）
【化１３】

構造式（ｋ）
【化１４】

【００５０】
参考例１１
参考例１において用いたオキシチタニウムフタロシアニンを下記構造式のビスアゾ顔料に代えた他は、参考例１と同様の条件で電子写真感光体を作成し、同様の評価を行った。結果を表２６に示す。
【化１５】

【００５１】
参考例１２
参考例１１で用いた有機正孔輸送物質（ａ）に代えて（ｂ）２．５ｇ及び（ｄ）２．５ｇを用いた他は、参考例１１と同様の条件で電子写真感光体を作成し、同様の評価を行った。結果を表２６に示す。
【００５２】
比較例４
参考例１１において有機電子輸送物質を除いた他は、参考例１１と同様の条件で電子写真感光体を作成し、同様の評価を行った。結果を表２６に示す。
【００５３】
比較例５
参考例１２において有機電子輸送物質を除いた他は、参考例１２と同様の条件で電子写真感光体を作成し、同様の評価を行った。結果を表２６に示す。
【００５４】
参考例１３
参考例１に用いた感光層上に下記の方法で保護層を形成した。
【００５５】
結着樹脂として下記構造式のアクリルモノマ−２５部、
【化１６】

光開始剤として２−メチルチオキサントン２部、平均粒径０．０２μｍのアンチモン含有酸化スズ微粒子（商品名Ｔ−１、三菱マテリアル（株）製）５０部及びトルエン３００部を混合しサンドミルで７２時間分散して保護層用の塗工液を調製した。この塗工液を参考例１におけると同様の感光層上にスプレ−塗工にて成膜し、乾燥後高圧水銀灯にて８００ｍＷ／ｃｍ^２の光強度で５秒間紫外線照射して膜厚３μｍの保護層を形成し、電子写真感光体を作成した。この電子写真感光体を参考例１と同様の評価を行った。結果を表２６に示す。
【００５６】
【表２５】

【表２６】

【００５７】
参考例１４
参考例１において用いた化合物例（１）の有機電子輸送物質に代えて化合物例（８５）の有機電子輸送物質を用いた他は、参考例１と同様にして単層型電子写真感光体を作成し、同様の評価を行った。結果を表２７に示す。
【００５８】
参考例１５〜２３
参考例１４で用いた有機正孔輸送物質、有機電子輸送物質を表２７に示すように代えた他は、参考例１４と同様にして電子写真感光体を作成し同様の評価を行った。結果を表２７に示す。
【００５９】
参考例２４
参考例１４において用いたオキシチタニウムフタロシアニンを参考例１１で用いたビスアゾ顔料に代えた他は、参考例１４と同様の条件で単層型電子写真感光体を作成し、同様の評価を行った。結果を表２８に示す。
【００６０】
参考例２５
参考例２４において用いた有機正孔輸送物質（ａ）に代えて（ｂ）を２．５ｇ及び（ｄ）を２．５ｇを用いた他は、参考例２３と同様の条件で単層型電子写真感光体を作成し、同様の評価を行った。結果を表２８に示す。
【００６１】
参考例２６
参考例１４で形成した感光層上に参考例１３におけると同様の条件で保護層を形成し、同様の評価を行った。結果を表２８に示す。
【００６２】
【表２７】

【表２８】

【００６３】
実施例１
参考例１において用いた化合物例（１）の有機電子輸送物質に代えて化合物例（１３５）の有機電子輸送物質を用いた他は、参考例１と同様にして単層型電子写真感光体を作成し、同様の評価を行った。
【００６４】
実施例２〜１０
実施例１で用いた有機正孔輸送物質、有機電子輸送物質を表２９に示すように代えた他は、実施例１と同様にして電子写真感光体を作成し同様の評価を行った。結果を表２９に示す。
【００６５】
実施例１１
実施例１において用いたオキシチタニウムフタロシアニンを参考例１１で用いたビスアゾ顔料に代えた他は、実施例１と同様の条件で単層型電子写真感光体を作成し、同様の評価を行った。結果を表３０に示す。
【００６６】
実施例１２
実施例１１において用いた有機正孔輸送物質（ａ）に代えて（ｂ）を２．５ｇ及び（ｄ）を２．５ｇを用いた他は、参考例２３と同様の条件で単層型電子写真感光体を作成し、同様の評価を行った。結果を表３０に示す。
【００６７】
実施例１３
実施例１で形成した感光層上に参考例１３におけると同様の条件で保護層を形成し、同様の評価を行った。結果を表３０に示す。
【００６８】
【表２９】

【表３０】

【００６９】
【発明の効果】
本発明の単層型の感光層よりなる電子写真感光体は、感度、帯電性に優れ、かつ、複写プロセスを繰り返しても極めて電位特性が安定しており、質の高い画像を安定的に供給することができるという顕著な効果を奏する。
【図面の簡単な説明】
【図１】本発明における単層型の感光層よりなる電子写真感光体の１例の該略図
【図２】本発明の電子写真感光体を有するプロセスカ−トリッジを有する電子写真装置の概略構成を示す図
【図３】本発明の電子写真感光体を有するファクシミリのブロックの例を示す図
【符号の説明】
１Ａ 導電性支持体
１Ｂ 感光層
１Ｂ１ 電荷発生物質
１Ｂ２ 有機正孔輸送物質及び有機電子輸送物質が結着樹脂中に分子分散され
た層
１ 本発明の電子写真感光体
２ 軸
３ 一次帯電手段
４ 画像露光光
５ 現像手段
６ 転写手段
７ 転写材
８ 像定着手段
９ クリ−ニング手段
１０ 前露光光
１１ プロセスカ−トリッジ
１２ レ−ル
１３ 画像読取部
１４ コントロ−ラ−
１５ 受信回路
１６ 送信回路
１７ 電話
１８ 回線
１９ 画像メモリ
２０ ＣＰＵ
２１ プリンタ−コントロ−ラ−
２２ プリンタ−[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a single layer type electrophotographic photosensitive member, a process cartridge including the electrophotographic photosensitive member, and an electrophotographic apparatus.
[0002]
[Prior art]
Conventionally, inorganic photoconductors having a photosensitive layer mainly composed of selenium, zinc oxide, cadmium and the like have been widely used as photoconductive materials used in electrophotographic photoconductors. Although these have some basic characteristics as a photoconductor, there are problems such as difficulty in film formation, poor plasticity, and high manufacturing costs. In addition, inorganic photoconductive materials are generally highly toxic and have significant limitations in manufacturing and handling.
[0003]
On the other hand, photoreceptors based on organic photoconductive materials have many advantages, such as compensating for the above-mentioned drawbacks of inorganic photoreceptors, and have attracted attention in recent years. Many proposals have been made and put to practical use. Has been. Such an organic photoreceptor is mainly composed of a charge transfer complex formed from a photoconductive polymer typified by polyvinylcarbazole and a Lewis acid such as 2,4,7-trinitro-9-fluorenone. An electrophotographic photosensitive member is proposed. These organic photoconductive polymers are superior to inorganic photoconductive materials in terms of lightness, film formability, and the like, but in terms of sensitivity, durability, safety, etc. It was inferior to that and was not always satisfactory.
[0004]
On the other hand, the function-separated electrophotographic photosensitive member in which the charge generation function and the charge transport function are assigned to different substances has improved the sensitivity and durability, which have been regarded as the disadvantages of conventional organic photosensitive members. Such a function-separated type photoconductor has an advantage that a material selection range of the charge generation material and the charge transport material is wide, and an electrophotographic photoconductor having arbitrary characteristics can be produced relatively easily. .
[0005]
However, most of these function-separated type photoconductors are stacked type photoconductors in which a charge transport layer is laminated in this order on a charge generation layer, and this type of photoconductor is used in a negative charging process. The reason for adopting such a configuration is that in a photoreceptor formed by simply mixing the materials to be used, the fatigue phenomenon of chargeability, sensitivity, electrostatic characteristics, etc. is often below the practical level. On the other hand, in the laminated type photoconductor, these disadvantages are suppressed, and a charge transport layer having a high mechanical strength and capable of designing a film thickness is arranged on the surface, so that it is in a state where it is subjected to an electrophotographic process. This is because the photosensitive member can have sufficient mechanical durability.
[0006]
In addition, organic materials with sufficient charge mobility in high-speed electrophotographic processes have been limited to donor compounds having only hole transport properties in most cases, and electrostatic fatigue phenomena are minimized. In order to suppress and maintain the mechanical strength of the photoreceptor sufficiently in the state of being used in the process, the function of charge generation and charge transfer is separated into layers, and a hole transporting organic material is used. This is because a photoreceptor having a laminated structure in which a charge transport layer having a material is arranged on the surface is considered to be most rational. However, the fact is that such a function-separated type electrophotographic photosensitive member causes a new problem.
[0007]
One of the problems is that in electrophotographic devices using organic photoreceptors that are used for negative charging, the amount of ozone generated due to charging is large, which pollutes the environment and causes the photoreceptors to be oxidized and deteriorated. In order to prevent this, a system that does not generate ozone, a system that collects ozone in the apparatus, and the like are required, and there is a drawback that the process and the system are complicated. In addition, from the viewpoint of the production of the photoreceptor, it is a factor that raises costs such as several coating processes and accurate management of the film thickness of those layers.
[0008]
In view of these problems, it is understood that an electrophotographic photoreceptor using an organic material is preferably used for a positive charging process and / or a single layer type (a type having a single photosensitive layer). Further, if the photoconductor can be used in the negative charging process as it is or with slight changes, it is possible to provide a photoconductor having the advantage of being inexpensive and having a high degree of freedom in the use environment.
[0009]
In order to achieve these, many single-layer type photoreceptors have been proposed recently. For example, in JP-A-6-123985, JP-A-6-130688, JP-A-6-123981, JP-A-6-123984, etc., a charge generating substance, an organic hole transporting substance, and an organic electron are included in the photoreceptor. A photoreceptor in which a transport material is dispersed in a binder resin has been proposed. However, there are many points to be further improved, such as insufficient sensitivity of these photoreceptors, large potential fluctuations due to repeated use, and high residual potential.
[0010]
[Problems to be solved by the invention]
An object of the present invention is to provide an electrophotographic photosensitive member using a single-layer type photosensitive layer which is excellent in chargeability and sensitivity and has a high potential characteristic stability even in repeated electrophotographic processes. Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus using the electrophotographic photosensitive member.
[0011]
[Means for Solving the Problems]
A single layer type electrophotographic photosensitive member according to one embodiment of the present invention is provided with a single photosensitive layer directly on a conductive support or via an undercoat layer, and the photosensitive layer is at least a charge generating material. The organic hole transport material and the organic electron transport material are dispersed in the binder resin, and the organic electron transport material is a compound represented by the following general formula (1) :
[Formula 4]

In the formula, R ₁ , R ₂ , R ₃ and R ₄ may have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. A good aromatic ring group,-(CH = CH) p-NO ₂ ,-(CH = CH) q-R ₅ or

Above _{- (CH = CH) p-} NO 2, - (CH = CH) q-R 5 or embedded image

R ₅ and R ₆ represent an aromatic group having a nitro group or a heterocyclic group having a nitro group, and R ₇ has an alkyl group, an aralkyl group which may have a substituent, or a substituent. An aromatic ring group or a heterocyclic group which may have a substituent, p and q are integers of 0, 1, 2; r is an integer of 0, 1; and R ₆ And R ₇ may be bonded to each other directly or via a saturated hydrocarbon, an unsaturated hydrocarbon, an oxygen atom or a sulfur atom to form a ring.
[0012]
The single-layer electrophotographic photosensitive member according to one embodiment of the present invention is provided with a single-layer photosensitive layer directly or via an undercoat layer on a conductive support, and the photosensitive layer has at least charge generation. A substance, an organic hole transport material and an organic electron transport material are dispersed in a binder resin, and the organic electron transport material is a compound represented by the following general formula (2) :
[Chemical 7]

In the formula, R ₁ , R ₂ , R ₃ and R ₄ may have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. aromatic ring _{group, - (CH = CH) p} -NO 2, - (CH = CH) q-R 5 or embedded image

Above _{- (CH = CH) p-} NO 2, - (CH = CH) q-R 5 or embedded image

R ₅ and R ₆ represent an aromatic group having a nitro group or a heterocyclic group having a nitro group, and R ₇ has an alkyl group, an aralkyl group which may have a substituent, or a substituent. An aromatic ring group or a heterocyclic group which may have a substituent, p and q are integers of 0, 1, 2; r is an integer of 0, 1; and R ₆ And R ₇ may be bonded to each other directly or via a saturated hydrocarbon, an unsaturated hydrocarbon, an oxygen atom or a sulfur atom to form a ring.
[0013]
In the present invention, a single photosensitive layer is provided on a conductive support directly or through an undercoat layer, and at least a charge generating material, an organic hole transporting material and an organic electron transporting material are bound to the photosensitive layer. It is composed of a single-layer electrophotographic photosensitive member that is dispersed in a resin and the organic electron transporting material is a compound represented by the following general formula (3) :
General formula (3)
[Chemical Formula 10]

In the formula, R ₁ , R ₂ , R ₃ and R ₄ may have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. aromatic ring _{group, - (CH = CH) p} -NO 2, - (CH = CH) q-R 5 or embedded image

Wherein at least two of R _{1 to} R ₄ are — (CH═CH) p—NO ₂ , — (CH═CH) q—R _5, or

R ₅ and R ₆ represent an aromatic group having a nitro group or a heterocyclic group having a nitro group, and R ₇ has an alkyl group, an aralkyl group which may have a substituent, or a substituent. An aromatic ring group or a heterocyclic group which may have a substituent, p and q are integers of 0, 1, 2; r is an integer of 0, 1; and R ₆ And R ₇ may be bonded to each other directly or via a saturated hydrocarbon, an unsaturated hydrocarbon, an oxygen atom or a sulfur atom to form a ring.
[0014]
In addition, the present invention integrally supports at least one unit selected from the group consisting of the single layer type electrophotographic photosensitive member of the present invention and a charging unit, a developing unit and a cleaning unit, and is attached to and detached from the main body of the electrophotographic apparatus. It is composed of a process cartridge characterized by being free.
[0015]
The present invention also comprises an electrophotographic apparatus comprising the single layer type electrophotographic photosensitive member of the present invention, a charging means, an image exposing means, a developing means, and a transferring means.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
The single-layer type electrophotographic photosensitive member of the present invention is excellent in chargeability and sensitivity, is suitable for low-speed to high-speed electrophotographic processes, can control the spectral sensitivity range by selecting a charge generating material, and can be monochrome or full color. Therefore, the present invention can be applied to a photoconductor of a page printer using an LED or a laser for writing.
[0017]
In a conventional monolayer type electrophotographic photosensitive member in which a charge generation material is dispersed in a resin, the charge generation material also serves as a charge transport function and has good transportability for both holes and electrons. Because there is no, the sensitivity is low. Since the charge transportability is low, there are drawbacks such as an increase in residual potential and a decrease in charge potential during repeated use. In order to solve these disadvantages, a photoconductor in which a charge generation material and a hole transport material are dispersed in a resin has been proposed. However, in a photoconductor in which a hole transport material is simply added, the hole transport function is improved. Electron transport is still not sufficient because the charge generation material is responsible, and problems such as high residual potential and low potential stability during repeated use cannot be solved.
[0018]
In the present invention, at least a charge generating material, an organic hole transporting material and an organic electron transporting material are dispersed in the binder resin in the photosensitive layer, and the organic electron transporting material is a compound represented by the general formula (3). By using it, the above problems are solved. The reason why these problems are solved is not completely clear, but one is that the electron orbital conjugation in the molecule of the compound represented by the general formula (3) is widespread so that the electron transport property it is better, the electron injection property to the compound represented by the general formula (3) from the charge generating material to the energy level is low unbound level of the compound represented by the general formula to a further (3) This is considered to be due to the fact that electrons and holes generated by light absorption in the charge generating material are easily injected and transported to the compound represented by the general formula (3) and the organic hole transporting material due to the fact that it is high. It is done.
[0019]
The single-layer electrophotographic photosensitive member of the present invention will be described in more detail with reference to the drawings. FIG. 1 shows an example of a single-layer electrophotographic photosensitive member of the present invention. 1A is a conductive support, 1B is a photosensitive layer, 1B1 is a charge generating material, 1B2 is an organic hole transport in a binder resin. This represents a matrix in which a substance and an organic electron transporting substance ( compound represented by the general formula (3) ) are dispersed in a molecular form.
[0020]
In the photoreceptor of the present invention, the compound represented by the general formula (3) is added as an organic electron transport material as described above.
[0021]
Next, the compounds represented by general formula (1) and general formula (2) used in the photosensitive layer of the electrophotographic photosensitive member according to the reference example of the present invention, and the photosensitive layer of the electrophotographic photosensitive member according to the present invention are used. Typical examples of the compound represented by the general formula (3) are listed. However, it is not limited to these compounds.
[0022]
[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

[Table 6]

[0023]
[Table 7]

[Table 8]

[Table 9]

[Table 10]

[Table 11]

[Table 12]

[0024]
[Table 13]

[Table 14]

[Table 15]

[Table 16]

[Table 17]

[Table 18]

[Table 19]

[0025]
[Table 20]

[Table 21]

[Table 22]

[Table 23]

[Table 24]

[0026]
The amount of the organic electron transport material ( compound represented by the general formula (3)) in the present invention in the entire photosensitive layer 1B is 1 to 50 wt%, preferably 5 to 40 wt%.
[0027]
In the photoreceptor of the present invention, an organic hole transport material is included as an essential component. The role of the organic hole transport material in the photosensitive layer is to move holes generated in the charge generating material in the photosensitive layer. Due to this transport function, holes are not accumulated in the charge generation material, and the charge generation function of the charge generation material can be fully exhibited.
[0028]
Examples of the organic hole transport material used in the present invention include compounds having a triphenylamine moiety in the molecule, hydrazone compounds, triphenylmethane compounds, pyrazoline compounds, oxadiazol compounds, carbazole compounds, styryl compounds, butadiene series Examples thereof include donor compounds such as compounds, polysilane compounds, and polyvinylcarbazole. The ratio of the organic hole transport material to the photosensitive layer 1B is 15 wt% or more, preferably 20 to 50 wt%.
[0029]
The role of the binder resin in the photosensitive layer 1B is not only the good dispersion of the charge generating material and the molecular dispersion of the organic electron transport material and the organic hole transport material, but also the mechanical properties of the photosensitive layer required in the electrophotographic process. It also bears strength. For this reason, when the composition ratio of the binder resin is low, these characteristics are impaired. Therefore, the amount of the binder resin in the photosensitive layer cannot be extremely low. The proportion of the binder resin in the entire photosensitive layer 1B is 30 to 90 wt%, preferably 40 to 70 wt%.
[0030]
The binder resin used in the present invention is not particularly limited, and a commercially available resin can be used. Examples of resins that can be used as the binder resin for the photosensitive layer include polyester resins, polycarbonate resins, polystyrene resins, acrylic resins, fluororesins, cellulose, polyurethane resins, epoxy resins, silicone resins, and alkyds. Examples thereof include resins, vinyl chloride resins, vinyl chloride-vinyl acetate copolymer resins, and the like.
[0031]
In the present invention, the charge generating material is also an essential component in the photosensitive layer. Examples of charge generation materials that can be used in the present invention include particles of inorganic photoconductive materials such as selenium compounds, amorphous silicon, cadmium sulfide, and zinc oxide, bisazo pigments, trisazo pigments, phthalocyanine pigments, perylene pigments, quinacridone pigments, indigo. Examples thereof include pigments and polycyclic quinone pigments. The amount of these charge generating substances contained in the photosensitive layer 1B is 0.1 to 40 wt%, preferably 0.3 to 20 wt%.
[0032]
The photosensitive layer 1B of the present invention has a thickness of 5 to 100 [mu] m, and most preferably 7 to 35 [mu] m.
[0033]
Examples of the conductive support 1A used in the present invention include a metal plate such as aluminum, nickel, copper, and stainless steel, a metal drum or metal foil, a plastic film or glass on which a thin film such as tin oxide and copper iodide is deposited or coated. It is done.
[0034]
In the photoreceptor of the present invention, an undercoat layer can be provided between the support and the photosensitive layer for the purpose of improving the electrical conductivity and the adhesion between the support and the photosensitive layer. As the material for the undercoat layer, polyamide resin, polyvinyl alcohol, casein, polyvinyl pyrrolidone and the like can be used in addition to the resins mentioned in the binder resin examples used for the photosensitive layer. The thickness of the undercoat layer is from 0.01 to 20 μm, and optimally from 0.1 to 5 μm.
[0035]
Furthermore, the photoreceptor of the present invention may be provided with a surface protective layer on the photosensitive layer 1B for the purpose of improving durability and the like.
[0036]
The photoconductor of the present invention is prepared by dissolving the material in an organic solvent or dispersing it with a ball mill, sand mill, ultrasonic wave or the like to prepare a photosensitive layer forming solution, which is dipped or blade coated. What is necessary is just to apply | coat on the electroconductive support body 1A with a spray coating method etc., and to dry and form the photosensitive layer 1B.
[0037]
FIG. 2 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention. In the figure, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow centering on the two. In the rotating process, the photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by the primary charging unit 3, and then exposed to image exposure means (non-exposure means such as slit exposure and laser beam scanning exposure). The image exposure light 4 from the figure is received. In this way, electrostatic latent images are sequentially formed on the peripheral surface of the photoreceptor 1.
[0038]
The formed electrostatic latent image is then toner developed by the developing means 5, and the developed toner developed image is transferred from the sheet feeding unit (not shown) between the photoreceptor 1 and the transfer means 6. The transfer means 6 sequentially transfers the transfer material 7 fed in synchronization with the rotation. The transfer material 7 that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means 8, and subjected to image fixing, thereby being printed out as a copy (copy). The surface of the photoreceptor 1 after the image transfer is cleaned by removing the transfer residual toner by the cleaning means 9, and is further subjected to charge removal processing by the pre-exposure light 10 from the pre-exposure means (not shown). And repeatedly used for image formation. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required.
[0039]
In the present invention, a plurality of components such as the photosensitive member 1, the primary charging unit 3, the developing unit 5 and the cleaning unit 9 described above are integrally coupled as a process cartridge. The process cartridge may be configured to be attachable to and detachable from an electrophotographic apparatus main body such as a copying machine or a laser beam printer. For example, at least one of the primary charging means 3, the developing means 5 and the cleaning means 9 is integrally supported together with the photosensitive member 1 to form a cartridge, and the apparatus main body is used using a guide means such as a rail 12 of the apparatus main body. The process cartridge 11 can be attached and detached. Further, when the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 uses reflected light or transmitted light from the original, or reads the original with a sensor and converts it into a signal, and the image exposure light 4 is processed according to this signal. The light is emitted by scanning the laser beam, driving the LED array, driving the liquid crystal shutter array, and the like.
[0040]
On the other hand, when used as a facsimile printer, the image exposure light 4 becomes exposure light for printing received data. FIG. 2 is a block diagram showing an example of this case. The controller 14 controls the image reading unit 13 and the printer 22. The entire controller 14 is controlled by the CPU 20. The read data from the image reading unit 13 is transmitted to the other station through the transmission circuit 16. Data received from the other station is sent to the printer 22 through the receiving circuit 15. Predetermined image data is stored in the image memory. The printer controller-21 controls the printer-22. 17 is a telephone. An image received from the line 18 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 15, and then the image information is decoded by the CPU 20 and sequentially stored in the image memory 19. Is done. When an image of at least one page is stored in the image memory 19, the image of that page is recorded. The CPU 20 reads one page of image information from the image memory 19 and sends the decoded one page of image information to the printer controller-21. When the printer controller 21 receives image information of one page from the CPU 20, the printer controller 21 controls the printer 22 to record the image information of the page. The CPU 20 receives the next page during recording by the printer 22. In this way, the image is received and recorded.
[0041]
【Example】
Reference example 1
4 g of oxytitanyl phthalocyanine was dispersed in a sand mill for 48 hours together with a solution in which 7 g of polyvinyl butyral (degree of butyralization 65%, weight average molecular weight 35000) was dissolved in 85 g of cyclohexanone solvent.
[0042]
5 g of organic electron transport material of compound example (1), 4 g of organic hole transport material of the following structural formula (a)
[Chemical 7]

And 5 g of the previously prepared dispersion of oxytitanyl phthalocyanine was added to a solution of 9 g of Z-type polycarbonate resin (weight average molecular weight 30000) dissolved in 70 g of chlorobenzene, and further dispersed with a ball mill for 1 hour. A coating solution for the photosensitive layer was prepared.
[0043]
Next, a 5% methanol solution of polyamide resin (trade name Amilan CM-8000, manufactured by Toray Industries, Inc.) was applied on an aluminum substrate with a Myer bar to form an undercoat layer of 0.5 μm. Further, the photosensitive layer coating solution prepared earlier with a Myer bar was applied to prepare a single layer type electrophotographic photosensitive member having a film thickness after drying of 16 μm.
[0044]
An applied voltage of ± 6 KV was applied to the electrophotographic photosensitive member using an electrostatic copying paper testing apparatus (EPA-8100) manufactured by Kawaguchi Electric Co., Ltd., and the surface potential was charged positively or negatively to obtain an initial surface potential Va ( V) The surface potential Vd (V) after dark decay for 3 seconds and the exposure amount E _1/2 (lux · sec) required for the surface potential to attenuate to ½ when irradiated with a 20 lux light source. It was measured.
[0045]
Further, after the obtained photoreceptor sheet is attached on an aluminum cylinder, it is mounted on a remodeling machine of a copying machine NP-6060 (manufactured by Canon Inc.), surface potential: Vd = + 650 V, after exposure After setting the potential: Vl = + 200 V, copying was repeated 1000 times, and the subsequent surface potential: Vd ′ and post-exposure potential: Vl ′ were measured using a surface potentiometer. Further, the fluctuation amount of the surface potential after copying 1000 times: ΔVd = Vd−Vd ′ and the fluctuation amount of the post-exposure potential: ΔVl = Vl−Vl ′ were calculated, and the results are shown in Table 25.
[0046]
Reference Examples 2 to 10
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Reference Example 1 except that the organic hole transport material and organic electron transport material used in Reference Example 1 were changed as shown in Table 25. The results are shown in Table 25.
[0047]
The organic hole transport material used is a compound of the following structural formulas (b) to (i).
Structural formula (b)
[Chemical 8]

Structural formula (c)
[Chemical 9]

Structural formula (d)
[Chemical Formula 10]

Structural formula (e)
Embedded image

Structural formula (f)
Embedded image

Structural formula (g)
Embedded image

Structural formula (h)
Embedded image

Structural formula (i)
Embedded image

[0048]
Comparative Example 1
In Reference Example 1, an electrophotographic photosensitive member was prepared under the same conditions as in Reference Example 1 except that the organic electron transport material was omitted, and the same evaluation was performed. The results are shown in Table 25.
[0049]
Comparative Examples 2 and 3
An electrophotographic photosensitive member was prepared in the same manner as in Reference Example 1 except that the following structural formulas (j) and (k) were used instead of the organic electron transport material used in Reference Example 1, and the same evaluation was performed. . The results are shown in Table 25.
Structural formula (j)
Embedded image

Structural formula (k)
Embedded image

[0050]
Reference Example 11
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Reference Example 1 except that the oxytitanium phthalocyanine used in Reference Example 1 was replaced with a bisazo pigment having the following structural formula. The results are shown in Table 26.
Embedded image

[0051]
Reference Example 12
An electrophotographic photosensitive member was prepared under the same conditions as in Reference Example 11, except that 2.5 g and (d) 2.5 g were used instead of the organic hole transport material (a) used in Reference Example 11. The same evaluation was performed. The results are shown in Table 26.
[0052]
Comparative Example 4
An electrophotographic photosensitive member was prepared under the same conditions as in Reference Example 11 except that the organic electron transport material was omitted in Reference Example 11, and the same evaluation was performed. The results are shown in Table 26.
[0053]
Comparative Example 5
An electrophotographic photoreceptor was prepared under the same conditions as in Reference Example 12 except that the organic electron transport material was omitted in Reference Example 12, and the same evaluation was performed. The results are shown in Table 26.
[0054]
Reference Example 13
A protective layer was formed on the photosensitive layer used in Reference Example 1 by the following method.
[0055]
25 parts of an acrylic monomer having the following structural formula as a binder resin,
Embedded image

As a photoinitiator, 2 parts of 2-methylthioxanthone, 50 parts of antimony-containing tin oxide fine particles (trade name T-1, manufactured by Mitsubishi Materials Corporation) having an average particle size of 0.02 μm and 300 parts of toluene were mixed and 72 hours in a sand mill Dispersed to prepare a coating solution for the protective layer. This coating solution was formed on the same photosensitive layer as in Reference Example 1 by spray coating, dried, and then irradiated with ultraviolet light at a light intensity of 800 mW / cm ² for 5 seconds with a high-pressure mercury lamp to a film thickness of 3 μm. A protective layer was formed to produce an electrophotographic photoreceptor. This electrophotographic photoreceptor was evaluated in the same manner as in Reference Example 1. The results are shown in Table 26.
[0056]
[Table 25]

[Table 26]

[0057]
Reference Example 14
A single-layer electrophotographic photosensitive member was prepared in the same manner as in Reference Example 1 except that the organic electron transport material of Compound Example (85) was used instead of the organic electron transport material of Compound Example (1) used in Reference Example 1. A similar evaluation was made. The results are shown in Table 27.
[0058]
Reference Examples 15-23
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Reference Example 14 except that the organic hole transport material and organic electron transport material used in Reference Example 14 were changed as shown in Table 27. The results are shown in Table 27.
[0059]
Reference Example 24
A single-layer electrophotographic photosensitive member was prepared and evaluated in the same manner as in Reference Example 14 except that the oxytitanium phthalocyanine used in Reference Example 14 was replaced with the bisazo pigment used in Reference Example 11. The results are shown in Table 28.
[0060]
Reference Example 25
Single-layer type electrons under the same conditions as in Reference Example 23 except that 2.5 g of (b) and 2.5 g of (d) were used instead of the organic hole transport material (a) used in Reference Example 24 Photoconductors were prepared and evaluated in the same manner. The results are shown in Table 28.
[0061]
Reference Example 26
A protective layer was formed on the photosensitive layer formed in Reference Example 14 under the same conditions as in Reference Example 13, and the same evaluation was performed. The results are shown in Table 28.
[0062]
[Table 27]

[Table 28]

[0063]
Example 1
A single-layer electrophotographic photosensitive member was prepared in the same manner as in Reference Example 1 except that the organic electron transport material of Compound Example (135) was used instead of the organic electron transport material of Compound Example (1) used in Reference Example 1. A similar evaluation was made.
[0064]
Examples 2 to 10
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the organic hole transport material and organic electron transport material used in Example 1 were changed as shown in Table 29. The results are shown in Table 29.
[0065]
Example 11
A single-layer electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the oxytitanium phthalocyanine used in Example 1 was replaced with the bisazo pigment used in Reference Example 11. The results are shown in Table 30.
[0066]
Example 12
A single-layer electron was used under the same conditions as in Reference Example 23 except that 2.5 g of (b) and 2.5 g of (d) were used instead of the organic hole transport material (a) used in Example 11 . Photoconductors were prepared and evaluated in the same manner. The results are shown in Table 30.
[0067]
Example 13
A protective layer was formed on the photosensitive layer formed in Example 1 under the same conditions as in Reference Example 13, and the same evaluation was performed. The results are shown in Table 30.
[0068]
[Table 29]

[Table 30]

[0069]
【The invention's effect】
The electrophotographic photosensitive member comprising the single-layer type photosensitive layer of the present invention is excellent in sensitivity and chargeability, has extremely stable potential characteristics even after repeated copying processes, and stably supplies high-quality images. There is a remarkable effect that it can be done.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an example of an electrophotographic photoreceptor comprising a single-layer type photosensitive layer in the present invention. FIG. 2 is a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photoreceptor of the present invention. FIG. 3 is a diagram showing an example of a facsimile block having the electrophotographic photosensitive member of the present invention.
1A Conductive Support 1B Photosensitive Layer 1B1 Charge Generating Material 1B2 Layer 1 in which Organic Hole Transport Material and Organic Electron Transport Material are Molecularly Dispersed in Binder Resin 2 of the Present Invention 2 Axis 3 Primary Charging Means 4 Image Exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 Rail 13 Image reading unit 14 Controller
15 Receiving Circuit 16 Transmitting Circuit 17 Telephone 18 Line 19 Image Memory 20 CPU
21 Printer Controller
22 Printer

Claims (3)

A single photosensitive layer is provided on a conductive support directly or through an undercoat layer, and at least a charge generating material, an organic hole transporting material and an organic electron transporting material are dispersed in the binder resin. And the organic electron transport material is a compound represented by the following general formula (3) :
General formula (3)

(Wherein R ₁ , R ₂ , R ₃ and R ₄ have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. also aromatic ring _{group, - (CH = CH) p} -NO 2, - (CH = CH) q-R 5 or

Wherein at least two of R _{1 to} R ₄ are — (CH═CH) p—NO ₂ , — (CH═CH) q—R ₅ or

R ₅ and R ₆ represent an aromatic group having a nitro group or a heterocyclic group having a nitro group, and R ₇ has an alkyl group, an aralkyl group which may have a substituent, or a substituent. An aromatic ring group or a heterocyclic group which may have a substituent, p and q are integers of 0, 1, 2; r is an integer of 0, 1; and R ₆ And R ₇ may be bonded to each other directly or via a saturated hydrocarbon, unsaturated hydrocarbon, oxygen atom or sulfur atom to form a ring) . 2. A process comprising: an electrophotographic photosensitive member according to claim 1 ; and at least one unit selected from the group consisting of a charging unit, a developing unit, and a cleaning unit. cartridge. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1 , a charging unit, an image exposing unit, a developing unit, and a transferring unit.

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