JP3959949B2 - Electrophotographic photosensitive member, process cartridge equipped with the same, and electrophotographic image forming apparatus - Google Patents

Description

【００１７】
【化４】

【００１８】
次に、本発明の電子写真感光体について説明する。
本発明の感光体の層構成は、電荷発生物質と電荷輸送物質とがバインダ樹脂中に分散された単層構成、または、電荷発生物質を含む電荷発生層と電荷輸送物質を含む電荷輸送層が積層された構成を有するが、特には、導電性支持体上に電荷発生層／電荷輸送層を順次積層した機能分離型感光体が好ましい。
【００１９】
以下、上記機能分離型感光体を例に、本発明の感光体について説明する。
層構成としては、電荷発生層と電荷輸送層の上には、保護機能を合わせ持つ第２の電荷輸送、保護層を設けても良く、また、必要に応じて導電性支持体と感光層との間に中間層を設けてもよい。本発明の一般式（Ａ）で表される化合物を含有する層は、感光体中の何れの層にも用いることができるが、本発明の一般式（Ａ）で表される化合物は、繰り返し使用による残留電位上昇が少なく、電位安定性が良好で、かつクラックの発生やタルク、紙粉のフィルミングが少ない優れた表面特性を有することが特徴であり、請求項２に係る発明では、電荷輸送層に用いることが特徴である。
【００２０】
本発明の一般式（Ａ）で表される化合物の添加量は、電荷輸送層内における質量比として、０．１〜２０％、より好ましくは１〜１０％添加されることである。また、本発明の感光体に用いられる電荷輸送物質としては、特に制限はなく、公知の電荷輸送物質、例えば、トリアリールアミン化合物、トリアリールアミンスチリル化合物、ヒドラゾン化合物、ピラゾリン化合物、ブタジエン化合物が挙げられる。特には、請求項３に係る発明である、前記一般式（Ｂ）で表されるトリアリールアミンスチリル化合物を用いることが、好ましい。
【００２１】
前記一般式（Ｂ）において、Ｒ₁〜Ｒ₃は、各々水素原子、ハロゲン原子または炭素数１〜５のアルキル基、アルコキシ基を表す。ｊ、ｎ、ｍは０〜３の整数を表す。又、Ａｒは水素原子または前記Ｒ₁〜Ｒ₃で示す置換基を有しても良いアリール基を表す。アリール基の中では、特にフェニル基が好ましい。
【００２２】
次に、一般式（Ｂ）で表されるトリアリールアミンスチリル化合物の具体例について記載するが、これによって本発明の化合物が限定されるものではない。
【００２３】
【化５】

【００２４】
【化６】

【００２５】
【化７】

【００２６】
【化８】

【００２７】
本発明の感光体に用いられる電荷発生物質としては、特に制限はなく、公知のいずれのものも使用でき、例えば、以下のようなものが挙げられる。種々のフタロシアニン化合物、Ａ型、Ｂ型及びＹ型のチタニルフタロシアニン、Ｘ型及びτ型の無金属フタロシアニン、銅フタロシアニンに代表される他の金属フタロシアニン類、ナフタロシアニン類、またこれら２種のフタロシアニンの混晶が挙げられる。また、アゾ化合物、ピリリウム化合物、ペリレン系化合物、シアニン系化合物、スクアリウム化合物、多環キノン化合物が挙げられる。
【００２８】
本発明に係る感光層は、バインダ樹脂と本発明に係る化合物を適当な溶媒に溶解させて、必要に応じて電荷輸送物質、電荷発生物質と共に溶解又は分散させた塗布液を、例えば、アプリケーター、バーコーター、ディップコーター、円形スライドホッパー等を用いて塗布、加熱乾燥、架橋して形成することができる。
【００２９】
塗布液の調製に使用される溶媒としては、例えば、トルエン、キシレン等の炭化水素類；メチレンクロライド、１，２−ジクロルエタン等のハロゲン化炭化水素；メチルエチルケトン、シクロヘキサノン等のケトン類；酢酸エチル、酢酸ブチル等のエステル類；メタノール、エタノール、メチルセルソルブ、エチルセルソルブ等のアルコール類及びこの誘導体；テトラヒドロフラン、１，４−ジオキサン、１，３−ジオキソラン等のエーテル類；ピリジンやジエチルアミン等のアミン類；Ｎ，Ｎ−ジメチルホルムアミド等のアミド類；その他脂肪酸及びフェノール類；二硫化炭素や燐酸トリエチル等の硫黄、燐化合物等を用いることができ、また２種以上を併用しても良い。
【００３０】
本発明に係る感光層に使用されるバインダ樹脂としては、例えば、ポリスチレン、アクリル樹脂、メタクリル樹脂、塩化ビニル樹脂、酢酸ビニル樹脂、ポリビニルブチラール樹脂、エポキシ樹脂、ポリウレタン樹脂、フェノール樹脂、ポリエステル樹脂、アルキッド樹脂、ポリカーボネート樹脂、シリコーン樹脂、メラミン樹脂、並びに、これらの樹脂の繰り返し単位の中の２つ以上を含む共重合体樹脂が挙げられる。また、これらの絶縁性樹脂の他、ポリ−Ｎ−ビニルカルバゾール等の高分子有機半導体も使用できる。
【００３１】
本発明に係る感光層におけるバインダ樹脂と電荷発生物質との割合は、バインダ樹脂１００質量部に対し５０〜６００質量部が好ましい。また、バインダ樹脂と電荷輸送物質との割合は、バインダ樹脂１００質量部に対し１０〜１００質量部が好ましい。
【００３２】
本発明に係る感光層の膜厚は、電荷発生層にて０．０１〜１０μｍ、電荷輸送層においては１〜５０μｍが好ましい。また、感光層が単層構成の場合は１〜５０μｍが好ましい。
【００３３】
本発明に係る感光層を支持する導電性支持体としては、例えば、アルミニウム、ニッケルなどの金属板・金属ドラム、またはアルミニウム、酸化錫、酸化インジュウムなどを蒸着したプラスチックフィルム、あるいは導電性物質を塗布した紙、プラスチックフィルム、ドラム等を使用することができる。
【００３４】
本発明に係る中間層に用いられる材料としては、ポリアミド樹脂、塩化ビニル樹脂、酢酸ビニル樹脂、並びにこれらの樹脂の繰り返し単位の中の２つ以上を含む共重合体樹脂が挙げられる。また、シランカップリング剤、チタンカップリング剤等の有機金属化合物を熱硬化させた硬化性金属樹脂化合物が挙げられる。
【００３５】
また、本発明の感光体には、その他、感色性補正の染料や酸化防止剤等の添加剤を併用しても良い。
【００３６】
【発明の実施の形態】
本発明の電子写真感光体は、複写機、レーザープリンター、ＬＥＤプリンター、液晶シャッター式プリンター等の電子写真画像形成装置に適用することが出来るが、さらには電子写真技術を応用したディスプレー、記録、軽印刷、製版、ファクシミリ等の装置にも広く適用することが出来る。
【００３７】
次に、図１の本発明の一例を示す画像形成装置の断面図を用いて、プロセスカートリッジ及び電子写真画像形成装置について説明する。
【００３８】
図１において、１０は支持体のドラム表面に感光層を塗布し、その上にシロキサン樹脂を塗布した感光体ドラムで、接地されて時計方向に駆動される。１２はスコロトロン帯電器で、感光体ドラム１０周面に対し一様な帯電をコロナ放電により与える。このスコロトロン帯電器１２による帯電に先立ち、前画像での履歴を除去するのに、発光ダイオード等を用いた露光部１１による前露光を行って感光体ドラム周面の除電を行っても良い。
【００３９】
感光体ドラム１０への一様な帯電の後、像露光器１３により画像信号に基づいた像露光が行われる。この像露光器１３は図示していないレーザーダイオードを光源とする。回転するポリゴンミラー１３１、ｆθレンズを経て反射ミラー１３２によって光路を曲げられた光により感光体ドラム上の走査がなされ、感光体ドラム１０上に静電潜像が形成される。
【００４０】
その静電潜像は次いで現像器１４により現像される。感光体ドラム１０周縁にはイエロー、マゼンタ、シアン及びブラック等のトナーとキャリアからなる現像剤を内蔵した現像器１４が配置されていて、先ず１色の現像がマグネットを内蔵し現像剤を保持して回転する現像スリーブ１４１によって行われる。
【００４１】
現像剤は、例えば、フェライトをコアとしてその回りに絶縁性樹脂をコーティングしたキャリアと、ポリエステルを主材料にして色に応じた顔料、荷電制御剤、シリカ及び酸化チタン等を加えたトナーを有するもので、現像剤は図示していない層形成手段によって現像スリーブ１４１上に１００〜６００μｍの厚みに規制されて現像域へと搬送され現像が行われる。この時、通常は感光体ドラム１０と現像スリーブ１４１の間に直流及び交流のバイアスをかけて現像が行われる。
【００４２】
カラー画像形成に於いては、１色目の顕像化が終わった後に２色目の画像形成工程に入り、再びスコロトロン帯電器１２による一様な帯電が行われ、２色目の潜像形成が像露光器１３により行われ、次いで現像器１４により現像が行われ顕像化が終了する。３、４色目の画像形成も２色目と同様に行われ、感光体ドラム１０周面上に４色の顕像が形成される。一方、モノクロの電子写真装置では現像器１４は単色トナー１種で構成され、１回の現像で画像形成する。
【００４３】
記録紙Ｐは画像形成の後、転写のタイミングが整った時点で給紙ローラ１７の回転作動により転写域へ給紙される。転写域に於いては転写のタイミングに同期して感光体ドラム１０周面に転写ローラ（転写器）１８が圧接され、給紙された記録紙Ｐを狭着して多色像が一括して転写される。
【００４４】
次いで、記録紙Ｐは転写ローラ１８とほぼ同時に圧接状態とされた分離ブラシ（分離器）１９によって除電され、感光体ドラム１０より分離して定着装置２０に搬送され、熱ローラ２０１と圧着ローラ２０２の加熱、加圧によってトナーを溶着した後、排紙ローラ２１を介して装置外へ排出される。なお前記転写ローラ１８と分離ブラシ１９は記録紙Ｐの通過後、感光体ドラム１０周面より退避して次なるトナー像形成に備える。
【００４５】
一方、記録紙Ｐを分離した後の感光体ドラム１０はクリーニング器２２のブレード２２１の圧接により残留トナーを除去・清掃して再び露光部１１による徐電と帯電器１２による帯電を受けて次なる画像形成に備える。なお感光体上にトナー像を重ね合わせてカラー画像を形成する場合には、ブレード２２１はクリーニング後、直ちに感光体ドラム１０周面より退避する。２２２はガイドローラである。なお３０は感光体ドラム・帯電器・転写器・分離器・クリーニング器を一体化した着脱可能なプロセスカートリッジである。
【００４６】
電子写真画像形成装置としては、上述の感光体ドラム・帯電器・転写器・分離器・クリーニング器等の構成要素をプロセスカートリッジとして一体に結合して構成し、このユニットを装置本体に対して着脱可能な構成にしても良い。又、感光体ドラム・帯電器・転写器・分離器・クリーニング器の少なくとも一つを感光体ドラムと共に一体化してプロセスカートリッジを構成し、装置本体に対して着脱自在な単一ユニットとし、装置本体のレール等の案内手段で着脱可能な構成にしても良い。
【００４７】
像露光は、画像形成装置を複写機やプリンターとして使用する場合には、原稿からの反射光や透過光を感光体に照射すること、或いはセンサーで原稿を読み取り信号化し、この信号に従ってレーザービームの走査、ＬＥＤアレイの駆動、又は液晶シャッターアレイの駆動を行い感光体に光を照射することなどにより行われる。
【００４８】
尚、ファクシミリのプリンターとして使用する場合には、像露光器１３は受信データをプリントするための露光を行うことになる。画像イメージは、ハロゲンランプ、レーザービーム、ＬＥＤアレイ、又は液晶等の光源から感光体表面に照射される。
【００４９】
【実施例】
以下、実施例を挙げて本発明を具体的に説明するが、本発明の実施態様はこれらに限定されるものではない。尚、文中「部」とは「質量部」を表す。
【００５０】
実施例１
以下に、本発明の一般式（Ａ）の例示化合物の合成の一例として、例示化合物Ａ−２の合成例を示す。
【００５１】
バニリン４００ｇ（２．６３モル）とマロノニトリル１８３ｇ（２．７６モル）をイソプロパノール１．６Ｌに溶解し、ピペリジン５ｍｌを加えた後、撹拌下で７０〜８０℃に加熱し、３時間反応させた。反応終了後、反応液に水を加えて結晶を析出させ、濾取して乾燥後、エタノール／水混合溶剤より再結晶して、バニリデンマロノニトリル４５０ｇを得た。
【００５２】
得られたバニリデンマロノニトリル４００ｇ（２．００モル）をトルエン３．２Ｌ及びピリジン０．８Ｌに溶解し、撹拌下室温にて、４−クロロベンゾイルクロライド３６８ｇ（２．１モル）を滴下した。滴下終了後、さらに７０〜８０℃に加熱し１時間反応させた。反応終了後、反応液に水を加えてピリジン塩酸塩を溶解し、析出した目的物を濾取して乾燥後、アセトニトリル／ジメチルホルムアミド混合溶剤により再結晶して、例示化合物Ａ−２を５４０ｇ得た。
【００５３】
実施例２
《感光体の作製》
以下に記載の方法に従って、本発明の感光体である感光体１〜８及び比較感光体１〜４を作製した。
【００５４】
（感光体１の作製）
下記のようにして、本発明の感光体１を作製した。
【００５５】
直径８０ｍｍの円筒形アルミニウム製導電性基体上に、下記の中間層塗布液を浸漬塗布し、１０５℃にて２０分加熱硬化し、厚さ１．０μｍの中間層を形成した。
【００５６】
〈中間層塗布液〉
チタンカップリング剤：ＴＣ７５０（松本製薬社製） ３０部
シランカップリング剤：ＫＢＭ５０３（信越化学社製） １７部
イソプロパノール １５０部
その上に下記電荷発生層塗布液１を、円形スライドホッパーにて塗布し、膜厚０．３μｍの電荷発生層を形成した。
【００５７】
〈電荷発生層塗布液１〉
電荷発生物質：Ｘ線回折におけるブラッグ角２θが９．５度、２４．１度、
２７．２度を有するＹ型チタニルフタロシアニン顔料 １２部
ポリビニルブチラール樹脂：エスレックＢＬ−１（積水化学社製）２４部
酢酸ｔ−ブチル ３００部
上記を混合し、サンドグラインダーにて分散した。
【００５８】
その上に、下記の電荷輸送層塗布液１を、円形スライドホッパーにて塗布して、１１０℃、６０分加熱硬化し、膜厚２５μｍの電荷輸送層を形成した。
【００５９】
〈電荷輸送層塗布液１〉
電荷輸送物質：例示化合物ＣＴ−５ ２００部
ビスフェノールＺ型ポリカーボネート：ユーピロンＺ３００
（三菱瓦斯化学社製） ３００部
ヒンダートフェノール化合物：ＡＯ−１ ５部
例示化合物Ａ−２ １０部
１，２−ジクロロエタン ２０００部
（感光体２の作製）
上記感光体１において、例示化合物Ａ−２に代えて、例示化合物Ａ−５を用いた以外は同様にして感光体２を作製した。
【００６０】
（感光体３の作製）
上記感光体１において、例示化合物Ａ−２に代えて、例示化合物Ａ−７を用いた以外は同様にして感光体３を作製した。
【００６１】
（感光体４の作製）
上記感光体１において、例示化合物Ａ−２に代えて、例示化合物Ａ−１１を用いた以外は同様にして感光体４を作製した。
【００６２】
（感光体５の作製）
上記感光体１において、例示化合物Ａ−２に代えて、例示化合物Ａ−１９を用いた以外は同様にして感光体５を作製した。
【００６３】
（感光体６の作製）
上記感光体１において、電荷発生層塗布液１を下記電荷発生層塗布液２に、また電荷輸送層塗布液１を下記電荷輸送層塗布液２に変更した以外は同様にして感光体６を作製した。
【００６４】
〈電荷発生層塗布液２〉
電荷発生物質：Ｘ線回折におけるブラッグ角２θが７．５度、２２．４度、
２４．３度、２５．４度、２８．６度を有するＢ型チタニルフタロシアニン
顔料 １５部
ポリビニルブチラール樹脂：エスレックＢＬ−Ｓ（積水化学社製）２５部
メチルエチルケトン ３００部
〈電荷輸送層塗布液２〉
電荷輸送物質：例示化合物ＣＴ−５ ２００部
ビスフェノールＺ型ポリカーボネート：ユーピロンＺ３００
（三菱瓦斯化学社製） ３００部
酸化防止剤：サノールＬＳ−２６２６（三共社製） ５部
例示化合物Ａ−１ １０部
１，２−ジクロロエタン ２０００部
（感光体７の作製）
上記感光体６において、例示化合物Ａ−１に代えて、例示化合物Ａ−４を用いた以外は同様にして感光体７を作製した。
【００６５】
（感光体８の作製）
上記感光体６において、例示化合物Ａ−１に代えて、例示化合物Ａ−２０を用いた以外は同様にして感光体８を作製した。
【００６６】
（比較感光体１の作製）
感光体１の作製において、本発明に係る化合物Ａ−２を除いた他は同様にして、比較感光体１を作製した。
【００６７】
（比較感光体２の作製）
感光体１の作製において、本発明に係る化合物Ａ−２に代えて、シアノビニル化合物Ｒ−１を用いた以外は同様にして比較感光体２を作製した。
【００６８】
（比較感光体３の作製）
感光体６の作製において、本発明に係る化合物Ａ−１を除いた他は同様にして、比較感光体３を作製した。
【００６９】
（比較感光体４の作製）
感光体６の作製において、本発明に係る化合物Ａ−１に代えて、シアノビニル化合物Ｒ−２を用いた以外は同様にして比較感光体４を作製した。
【００７０】
【化９】

【００７１】
《感光体の評価》
上記作製した本発明の感光体１〜８及び比較感光体１〜４を、それぞれコニカ社製のデジタルコピープリンタ機「Ｋｏｎｉｃａ７１５０」を改造し、露光量を適正化した評価機に装着した。初期帯電位を−８５０Ｖに設定して、３３℃、８０％ＲＨの高温高湿環境下（ＨＨ環境と称す）及び１５℃、３０％ＲＨの低温低湿環境下（ＬＬ環境と称す）にて、各々５万回の実写試験を行い、複写画像及び感光体表面の異物付着を観察し、また実写試験前後での未露光部電位ＶＨ及び露光部電位ＶＬを測定した。また、別途強制クラック試験として、感光体ドラムをドラムカートリッジに装着し、クリーニングローラーを感光体に圧着させた状態で、５０℃の恒温槽中に１０００時間放置し、クラック発生の有無を調べた。以上により、得られた結果を表１に示す。
【００７２】
【表１】

【００７３】
表１より明らかなように、各環境下の実写試験において、本発明の感光体１〜８を用いた水準は、所定プリント終了まで良好な画像を与え、かつ実写後の感光体表面も清浄なものであった。これに対して、比較感光体１、３を用いた水準では、特にＨＨ環境下の画像において、４．５万プリント時付近からカブリが生じ、ＬＬ環境下の画像では４．７万プリント時付近から濃度低下が生じ、細線の再現性が不十分である。また、比較感光体２、４を用いた水準では、特にＨＨ環境下の画像でフィルミングに起因した画像ボケが生じ、微少なクラックによる画像欠陥が認められた。また、クラック試験では、本発明に係る水準では全くクラックの発生が認められなかったのに対し、比較感光体を用いた水準は、すべての感光体でクラックの発生が認められ、本発明に係る感光体の優れた耐クラック性を確認することができた。
【００７４】
【発明の効果】
本発明により、繰り返し使用による残留電位上昇が少なく電位安定性が良好で、またクラックの発生やタルク、紙粉のフィルミングが少ない優れた表面特性を有する耐久性に優れた電子写真感光体、それを搭載したプロセスカートリッジ及び電子写真画像形成装置を提供することができた。
【図面の簡単な説明】
【図１】本発明の一例を示す画像形成装置の断面図である。
【符号の説明】
１０ 感光体ドラム（又は感光体）
１１ 露光部
１２ スコロトロン帯電器
１３ 像露光器
１４ 現像器
１７ 給紙ローラ
１８ 転写ローラ（転写器）
１９ 分離ブラシ（分離器）
２０ 定着装置
２１ 排紙ローラ
２２ クリーニング器
３０ プロセスカートリッジ
１３１ ポリゴンミラー
１３２ 反射ミラー
１４１ 現像スリーブ
２０１ 熱ローラ
２０２ 圧着ローラ
２２１ ブレード
２２２ ガイドローラ
Ｐ 記録紙[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic photoreceptor (hereinafter also simply referred to as a photoreceptor), a process cartridge equipped with the electrophotographic photoreceptor and an electrophotographic image forming apparatus (hereinafter also simply referred to as an image forming apparatus).
[0002]
[Prior art]
Conventionally, as an electrophotographic photoreceptor, an inorganic photoreceptor having a photosensitive layer mainly composed of an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide, or silicon has been widely used. However, these inorganic photoreceptors are not always satisfactory in sensitivity, thermal stability, moisture resistance, durability and the like, and some inorganic photoreceptors contain substances harmful to the human body. Therefore, there is a problem in disposal.
[0003]
In order to overcome the disadvantages of these inorganic photoreceptors, research and development of organic photoreceptors having a photosensitive layer mainly composed of various organic photoconductive compounds have been actively conducted in recent years. In particular, the function-separated type photoconductor in which the charge generation function and the charge transport function are respectively assigned to different substances can be selected from a wide range of materials. Since it can be easily produced, many studies have been made, and some have been put into practical use.
[0004]
However, the function-separated type photoreceptors known so far have increased residual potential, decreased charged potential, fluctuation in sensitivity, etc. when used repeatedly, and there has been a demand for further improvement in terms of potential stability. As a technical countermeasure against such a photoreceptor potential fluctuation, a method for adding various deterioration preventing / stabilizing agents to the photoreceptor has been studied. For example, in Japanese Patent Application Laid-Open Nos. 58-7643, 03-48852, 03-71141, 05-45902, 06-27691, 06-102684, electron-withdrawing compounds, cyanovinyl compounds, etc. A method of adding is proposed.
[0005]
As described in the above specification, these electron-withdrawing compounds and cyanovinyl compounds are mainly added to the charge transport layer, which is the outermost surface layer of the photoreceptor, in combination with a charge transport material and a binder resin. In this case, the increase in residual potential is suppressed by the addition of the compound, but depending on the type of the charge transport material and the binder resin, cracks caused by the inhibition of compatibility under specific environmental conditions. As a result, problems such as generation of foreign matter and adhesion of foreign matter (talc, paper dust filming) to the surface of the photosensitive member are caused, and immediate improvement is desired.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and its purpose is to improve residual potential with little residual potential increase due to repeated use, excellent potential stability, and excellent surface characteristics with less cracking, talc, and filming of paper dust. And an electrophotographic photosensitive member having excellent durability, a process cartridge having the electrophotographic photosensitive member mounted thereon, and an electrophotographic image forming apparatus.
[0007]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following constitution.
[0008]
1. An electrophotographic photosensitive member having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains the compound represented by the general formula (A).
[0009]
2. A photosensitive layer having a structure in which a charge generation layer and a charge transport layer are laminated on a conductive support, and the charge transport layer contains the compound represented by the general formula (A) and a charge transport material. 2. The electrophotographic photosensitive member according to 1 above, wherein
[0010]
3. 3. The electrophotographic photoreceptor according to item 2, wherein the charge transport material is a triarylamine styryl compound represented by the general formula (B).
[0011]
4). An electrophotographic image forming, wherein an image is formed through each step of charging, image exposure, development, transfer, separation, and cleaning using the electrophotographic photosensitive member according to any one of items 1 to 3. apparatus.
[0012]
5). The electrophotographic photosensitive member according to any one of items 1 to 3, wherein the electrophotographic photosensitive member is used for image formation through the steps of charging, image exposure, development, transfer, separation, and cleaning. A process cartridge manufactured using a body in combination with at least one selected from a charging device, an image exposure device, a developing device, a transfer or separation device, and a cleaning device.
[0013]
Details of the present invention will be described below.
The invention according to claim 1 is characterized in that in the electrophotographic photosensitive member in which a photosensitive layer is provided on a conductive support, the photosensitive layer contains the compound represented by the general formula (A).
[0014]
In the general formula (A), Ar represents a substituted or unsubstituted aromatic group. Examples of the aromatic group include phenyl, 1-naphthyl, 2-naphthyl and the like, and a phenyl group is particularly preferable. In addition, the aromatic group Ar may further contain the following groups such as an alkyl group, an alkoxy group, a halogen group, a cyano group, and a nitro group as substituents. Examples of the alkyl group include methyl, Examples include groups such as ethyl, propyl, isopropyl, butyl, and t-butyl. Examples of the alkoxy group include groups such as methoxy, ethoxy, propyloxy, and butoxy. Examples of the halogen group include chlorine, bromine, fluorine, and iodine groups. In particular, a halogen group is preferred as the group that substitutes for the aromatic group Ar.
[0015]
Next, although the specific example of a compound represented by general formula (A) of this invention is described, the compound of this invention is not limited by this.
[0016]
[Chemical 3]

[0017]
[Formula 4]

[0018]
Next, the electrophotographic photoreceptor of the present invention will be described.
The layer structure of the photoreceptor of the present invention includes a single layer structure in which a charge generation material and a charge transport material are dispersed in a binder resin, or a charge generation layer including a charge generation material and a charge transport layer including a charge transport material. In particular, a function-separated type photoreceptor in which a charge generation layer / a charge transport layer are sequentially laminated on a conductive support is preferable.
[0019]
Hereinafter, the photoreceptor of the present invention will be described by taking the function-separated photoreceptor as an example.
As the layer structure, a second charge transporting / protecting layer having a protective function may be provided on the charge generating layer and the charge transporting layer, and the conductive support and the photosensitive layer may be provided as necessary. An intermediate layer may be provided between them. The layer containing the compound represented by the general formula (A) of the present invention can be used for any layer in the photoreceptor, but the compound represented by the general formula (A) of the present invention is repeatedly used. The residual potential rise due to use is small, the potential stability is good, and there is an excellent surface characteristic that the generation of cracks, talc, and filming of paper powder is small. It is characterized by being used for the transport layer.
[0020]
The addition amount of the compound represented by the general formula (A) of the present invention is 0.1 to 20%, more preferably 1 to 10% as a mass ratio in the charge transport layer. The charge transport material used in the photoreceptor of the present invention is not particularly limited, and examples thereof include known charge transport materials such as triarylamine compounds, triarylamine styryl compounds, hydrazone compounds, pyrazoline compounds, and butadiene compounds. It is done. In particular, it is preferable to use the triarylamine styryl compound represented by the general formula (B), which is the invention according to claim 3.
[0021]
In the general formula (B), R _{1 to} R ₃ each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkoxy group. j, n, and m represent an integer of 0 to 3. Ar represents a hydrogen atom or an aryl group which may have a substituent represented by R _{1 to} R ₃ . Of the aryl groups, a phenyl group is particularly preferable.
[0022]
Next, although the specific example of the triarylamine styryl compound represented by general formula (B) is described, the compound of this invention is not limited by this.
[0023]
[Chemical formula 5]

[0024]
[Chemical 6]

[0025]
[Chemical 7]

[0026]
[Chemical 8]

[0027]
The charge generating material used in the photoreceptor of the present invention is not particularly limited, and any known material can be used, and examples include the following. Various phthalocyanine compounds, A-type, B-type and Y-type titanyl phthalocyanines, X-type and τ-type metal-free phthalocyanines, other metal phthalocyanines typified by copper phthalocyanine, naphthalocyanines, and these two phthalocyanines Examples include mixed crystals. In addition, azo compounds, pyrylium compounds, perylene compounds, cyanine compounds, squalium compounds, and polycyclic quinone compounds are exemplified.
[0028]
The photosensitive layer according to the present invention is prepared by dissolving a binder resin and a compound according to the present invention in a suitable solvent, and, if necessary, a coating solution obtained by dissolving or dispersing together with a charge transport material and a charge generation material, for example, an applicator, It can be formed by coating, heat drying and crosslinking using a bar coater, dip coater, circular slide hopper or the like.
[0029]
Examples of the solvent used for preparing the coating solution include hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as methylene chloride and 1,2-dichloroethane; ketones such as methyl ethyl ketone and cyclohexanone; ethyl acetate and acetic acid. Esters such as butyl; Alcohols such as methanol, ethanol, methyl cellosolve and ethyl cellosolve and derivatives thereof; Ethers such as tetrahydrofuran, 1,4-dioxane and 1,3-dioxolane; Amines such as pyridine and diethylamine Amides such as N, N-dimethylformamide; other fatty acids and phenols; sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate may be used, and two or more of them may be used in combination.
[0030]
Examples of the binder resin used in the photosensitive layer according to the present invention include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, and alkyd. Examples thereof include resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of these resin repeating units. In addition to these insulating resins, polymer organic semiconductors such as poly-N-vinylcarbazole can also be used.
[0031]
The ratio of the binder resin and the charge generating material in the photosensitive layer according to the present invention is preferably 50 to 600 parts by mass with respect to 100 parts by mass of the binder resin. Further, the ratio of the binder resin to the charge transport material is preferably 10 to 100 parts by mass with respect to 100 parts by mass of the binder resin.
[0032]
The film thickness of the photosensitive layer according to the present invention is preferably 0.01 to 10 μm in the charge generation layer and 1 to 50 μm in the charge transport layer. Further, when the photosensitive layer has a single layer structure, 1 to 50 μm is preferable.
[0033]
As the conductive support for supporting the photosensitive layer according to the present invention, for example, a metal plate or a metal drum such as aluminum or nickel, or a plastic film on which aluminum, tin oxide, indium oxide or the like is deposited, or a conductive material is applied. Paper, plastic film, drums, etc. can be used.
[0034]
Examples of the material used for the intermediate layer according to the present invention include polyamide resins, vinyl chloride resins, vinyl acetate resins, and copolymer resins containing two or more repeating units of these resins. Moreover, the curable metal resin compound which thermosetted organometallic compounds, such as a silane coupling agent and a titanium coupling agent, is mentioned.
[0035]
In addition, additives such as dyes for color sensitivity correction and antioxidants may be used in combination with the photoreceptor of the present invention.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
The electrophotographic photosensitive member of the present invention can be applied to electrophotographic image forming apparatuses such as copying machines, laser printers, LED printers, and liquid crystal shutter printers. The present invention can be widely applied to apparatuses such as printing, plate making and facsimile.
[0037]
Next, the process cartridge and the electrophotographic image forming apparatus will be described with reference to the cross-sectional view of the image forming apparatus shown in FIG.
[0038]
In FIG. 1, reference numeral 10 denotes a photosensitive drum in which a photosensitive layer is coated on the drum surface of a support and a siloxane resin is coated thereon, and is grounded and driven clockwise. A scorotron charger 12 applies uniform charging to the circumferential surface of the photosensitive drum 10 by corona discharge. Prior to charging by the scorotron charger 12, in order to remove the history in the previous image, pre-exposure by the exposure unit 11 using a light emitting diode or the like may be performed to neutralize the peripheral surface of the photosensitive drum.
[0039]
After uniform charging of the photosensitive drum 10, the image exposure unit 13 performs image exposure based on the image signal. The image exposure unit 13 uses a laser diode (not shown) as a light source. Scanning on the photosensitive drum is performed by the light whose optical path is bent by the reflecting mirror 132 via the rotating polygon mirror 131 and the fθ lens, and an electrostatic latent image is formed on the photosensitive drum 10.
[0040]
The electrostatic latent image is then developed by the developing device 14. On the periphery of the photosensitive drum 10, a developing device 14 containing a developer composed of toner, such as yellow, magenta, cyan, and black, and a carrier is disposed. First, one color developer contains a magnet and holds the developer. The developing sleeve 141 is rotated.
[0041]
The developer includes, for example, a carrier in which ferrite is used as a core and an insulating resin is coated around the carrier, and a toner including polyester as a main material and a pigment corresponding to a color, a charge control agent, silica, titanium oxide, and the like. Thus, the developer is regulated to a thickness of 100 to 600 μm on the developing sleeve 141 by a layer forming means (not shown), and is conveyed to the developing area for development. At this time, development is usually performed by applying a direct current or alternating current bias between the photosensitive drum 10 and the developing sleeve 141.
[0042]
In the color image formation, after the first color visualization is completed, the second color image formation process is started, and uniform charging is performed again by the scorotron charger 12, and the second color latent image formation is the image exposure. Then, development is performed by the developing device 14 and then development is performed by the developing device 14 to complete the visualization. The third and fourth color images are formed in the same manner as the second color, and a four-color visible image is formed on the circumferential surface of the photosensitive drum 10. On the other hand, in the monochrome electrophotographic apparatus, the developing device 14 is composed of one type of monochromatic toner, and forms an image by one development.
[0043]
The recording paper P is fed to the transfer area by the rotation operation of the paper feed roller 17 when the transfer timing is ready after image formation. In the transfer area, a transfer roller (transfer device) 18 is pressed against the circumferential surface of the photosensitive drum 10 in synchronism with the transfer timing, and the fed recording paper P is tightly attached to form a multicolor image all at once. Transcribed.
[0044]
Next, the recording paper P is neutralized by a separation brush (separator) 19 brought into a pressure contact state almost simultaneously with the transfer roller 18, separated from the photosensitive drum 10 and conveyed to the fixing device 20, and a heat roller 201 and a pressure roller 202. After the toner is welded by heating and pressurizing, the toner is discharged out of the apparatus through the paper discharge roller 21. The transfer roller 18 and the separation brush 19 are retracted from the circumferential surface of the photosensitive drum 10 after the recording paper P has passed to prepare for the next toner image formation.
[0045]
On the other hand, after the recording paper P is separated, the photosensitive drum 10 is subjected to the removal of the residual toner by the pressure contact of the blade 221 of the cleaning device 22 and cleaning, and then the slow charging by the exposure unit 11 and the charging by the charger 12 are performed again. Prepare for image formation. When forming a color image by superimposing a toner image on the photoconductor, the blade 221 is retracted from the circumferential surface of the photoconductor drum 10 immediately after cleaning. Reference numeral 222 denotes a guide roller. Reference numeral 30 denotes a removable process cartridge in which a photosensitive drum, a charger, a transfer device, a separator, and a cleaning device are integrated.
[0046]
As an electrophotographic image forming apparatus, the above-described components such as a photosensitive drum, a charger, a transfer device, a separator, and a cleaning device are integrally connected as a process cartridge, and this unit is attached to and detached from the apparatus main body. A possible configuration may be adopted. In addition, at least one of the photosensitive drum, charger, transfer unit, separator, and cleaning unit is integrated with the photosensitive drum to form a process cartridge, which is a single unit that can be attached to and detached from the apparatus body. It may be configured to be detachable by guide means such as rails.
[0047]
When the image forming apparatus is used as a copying machine or a printer, image exposure is performed by irradiating a photosensitive member with reflected light or transmitted light from a document, or by reading a document with a sensor and converting a laser beam in accordance with this signal. Scanning, driving the LED array, or driving the liquid crystal shutter array and irradiating the photosensitive member with light are performed.
[0048]
When used as a facsimile printer, the image exposure unit 13 performs exposure for printing received data. The image is irradiated on the surface of the photoreceptor from a light source such as a halogen lamp, laser beam, LED array, or liquid crystal.
[0049]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, the embodiment of this invention is not limited to these. In the text, “part” means “part by mass”.
[0050]
Example 1
Below, the synthesis example of exemplary compound A-2 is shown as an example of the synthesis | combination of the exemplary compound of general formula (A) of this invention.
[0051]
400 g (2.63 mol) of vanillin and 183 g (2.76 mol) of malononitrile were dissolved in 1.6 L of isopropanol. After adding 5 ml of piperidine, the mixture was heated to 70 to 80 ° C. with stirring and reacted for 3 hours. After completion of the reaction, water was added to the reaction solution to precipitate crystals, which were collected by filtration, dried and recrystallized from an ethanol / water mixed solvent to obtain 450 g of vanidene malononitrile.
[0052]
400 g (2.00 mol) of the obtained vanylidene malononitrile was dissolved in 3.2 L of toluene and 0.8 L of pyridine, and 368 g (2.1 mol) of 4-chlorobenzoyl chloride was added dropwise at room temperature with stirring. After completion of dropping, the mixture was further heated to 70 to 80 ° C. and reacted for 1 hour. After completion of the reaction, water is added to the reaction solution to dissolve pyridine hydrochloride, and the precipitated target product is collected by filtration, dried and recrystallized with a mixed solvent of acetonitrile / dimethylformamide to obtain 540 g of Exemplified Compound A-2. It was.
[0053]
Example 2
<< Production of photoconductor >>
In accordance with the method described below, photoconductors 1 to 8 and comparative photoconductors 1 to 4 which are photoconductors of the present invention were prepared.
[0054]
(Preparation of photoreceptor 1)
The photoreceptor 1 of the present invention was produced as follows.
[0055]
The following intermediate layer coating solution was dip-coated on a cylindrical aluminum conductive substrate having a diameter of 80 mm and cured by heating at 105 ° C. for 20 minutes to form an intermediate layer having a thickness of 1.0 μm.
[0056]
<Intermediate layer coating solution>
Titanium coupling agent: TC750 (manufactured by Matsumoto Pharmaceutical Co., Ltd.) 30 parts Silane coupling agent: KBM503 (manufactured by Shin-Etsu Chemical Co., Ltd.) 17 parts Isopropanol 150 parts The following charge generation layer coating solution 1 is applied with a circular slide hopper. A charge generation layer having a thickness of 0.3 μm was formed.
[0057]
<Charge generation layer coating solution 1>
Charge generation material: Bragg angle 2θ in X-ray diffraction is 9.5 degrees, 24.1 degrees,
Y-type titanyl phthalocyanine pigment having 27.2 degrees 12 parts polyvinyl butyral resin: Eslek BL-1 (manufactured by Sekisui Chemical Co., Ltd.) 24 parts t-butyl acetate 300 parts The above was mixed and dispersed with a sand grinder.
[0058]
On top of this, the following charge transport layer coating solution 1 was applied with a circular slide hopper and heated and cured at 110 ° C. for 60 minutes to form a charge transport layer having a thickness of 25 μm.
[0059]
<Charge transport layer coating solution 1>
Charge transport material: Exemplified compound CT-5 200 parts Bisphenol Z type polycarbonate: Iupilon Z300
(Mitsubishi Gas Chemical Co., Ltd.) 300 parts Hindered phenol compound: AO-1 5 parts Illustrative compound A-2 10 parts 1,2-dichloroethane 2000 parts (Preparation of photoreceptor 2)
Photoreceptor 2 was produced in the same manner as in Photoreceptor 1, except that Exemplified Compound A-5 was used instead of Exemplified Compound A-2.
[0060]
(Preparation of photoreceptor 3)
Photoconductor 3 was prepared in the same manner as in Photoconductor 1, except that Exemplified Compound A-7 was used instead of Exemplified Compound A-2.
[0061]
(Preparation of photoconductor 4)
Photoreceptor 4 was produced in the same manner as in Photoreceptor 1 except that Exemplified Compound A-11 was used instead of Exemplified Compound A-2.
[0062]
(Preparation of photoconductor 5)
Photoconductor 5 was prepared in the same manner as in Photoconductor 1, except that Exemplified Compound A-19 was used instead of Exemplified Compound A-2.
[0063]
(Preparation of photoreceptor 6)
A photoconductor 6 was prepared in the same manner as in the photoconductor 1 except that the charge generation layer coating solution 1 was changed to the following charge generation layer coating solution 2 and the charge transport layer coating solution 1 was changed to the following charge transport layer coating solution 2. did.
[0064]
<Charge generation layer coating solution 2>
Charge generation material: Bragg angle 2θ in X-ray diffraction is 7.5 degrees, 22.4 degrees,
B-type titanyl phthalocyanine pigment having 24.3 degrees, 25.4 degrees, and 28.6 degrees 15 parts polyvinyl butyral resin: ESREC BL-S (manufactured by Sekisui Chemical Co., Ltd.) 25 parts methyl ethyl ketone 300 parts <Charge transport layer coating solution 2>
Charge transport material: Exemplified compound CT-5 200 parts Bisphenol Z type polycarbonate: Iupilon Z300
(Mitsubishi Gas Chemical Co., Ltd.) 300 parts Antioxidant: Sanol LS-2626 (Sankyo Co., Ltd.) 5 parts Illustrative compound A-1 10 parts 1,2-dichloroethane 2000 parts (Preparation of photoreceptor 7)
Photoreceptor 7 was produced in the same manner as Example 6 except that Exemplified Compound A-4 was used in place of Exemplified Compound A-1.
[0065]
(Preparation of photoconductor 8)
Photoreceptor 8 was produced in the same manner as Example 6 except that Exemplified Compound A-20 was used in place of Exemplified Compound A-1.
[0066]
(Preparation of comparative photoreceptor 1)
Comparative photoconductor 1 was produced in the same manner as in the production of photoconductor 1, except that compound A-2 according to the present invention was omitted.
[0067]
(Preparation of comparative photoreceptor 2)
In the production of the photoreceptor 1, a comparative photoreceptor 2 was produced in the same manner except that the cyanovinyl compound R-1 was used instead of the compound A-2 according to the present invention.
[0068]
(Preparation of comparative photoreceptor 3)
A comparative photoreceptor 3 was produced in the same manner as in the production of the photoreceptor 6 except that the compound A-1 according to the present invention was omitted.
[0069]
(Preparation of comparative photoconductor 4)
Comparative photoconductor 4 was prepared in the same manner except that cyanovinyl compound R-2 was used in place of compound A-1 according to the present invention.
[0070]
[Chemical 9]

[0071]
<< Evaluation of photoconductor >>
The photoconductors 1 to 8 and the comparative photoconductors 1 to 4 of the present invention prepared above were mounted on an evaluation machine in which the digital copy printer “Konica 7150” manufactured by Konica was remodeled and the exposure amount was optimized. With the initial charged potential set to -850 V, in a high temperature and high humidity environment of 33 ° C. and 80% RH (referred to as HH environment) and in a low temperature and low humidity environment of 15 ° C. and 30% RH (referred to as LL environment), Each 50,000 shots were carried out to observe adhesion of foreign matter on the copied image and the photoreceptor surface, and the unexposed portion potential VH and the exposed portion potential VL before and after the shoot test were measured. As a separate forced crack test, the photosensitive drum was mounted on a drum cartridge, and the cleaning roller was pressure-bonded to the photosensitive member, and was left in a thermostatic bath at 50 ° C. for 1000 hours to examine whether cracks occurred. The results thus obtained are shown in Table 1.
[0072]
[Table 1]

[0073]
As is apparent from Table 1, in the actual shooting test under each environment, the level using the photoconductors 1 to 8 of the present invention gives a good image until the end of the predetermined printing, and the surface of the photoconductor after the actual shooting is also clean. It was a thing. On the other hand, with the level using the comparative photoconductors 1 and 3, fog is generated from around 45,000 prints particularly in an image in an HH environment, and around 47,000 prints in an image in an LL environment. As a result, the density decreases, and the reproducibility of the thin line is insufficient. Further, at the level using the comparative photoconductors 2 and 4, image blur caused by filming occurred particularly in an image in an HH environment, and image defects due to minute cracks were recognized. Further, in the crack test, no cracks were observed at the level according to the present invention, whereas cracks were observed on all the photoconductors at the level using the comparative photoconductor. The excellent crack resistance of the photoreceptor could be confirmed.
[0074]
【The invention's effect】
According to the present invention, an electrophotographic photoreceptor excellent in durability having excellent surface characteristics with little increase in residual potential due to repeated use, good potential stability, and few occurrence of cracks, talc and filming of paper dust, and And a process cartridge and an electrophotographic image forming apparatus equipped with the above can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an image forming apparatus showing an example of the present invention.
[Explanation of symbols]
10 Photosensitive drum (or photoconductor)
DESCRIPTION OF SYMBOLS 11 Exposure part 12 Scorotron charger 13 Image exposure device 14 Developing device 17 Paper feed roller 18 Transfer roller (transfer device)
19 Separation brush (separator)
20 fixing device 21 paper discharge roller 22 cleaning device 30 process cartridge 131 polygon mirror 132 reflection mirror 141 developing sleeve 201 heat roller 202 pressure roller 221 blade 222 guide roller P recording paper

Claims (5)

An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, wherein the photosensitive layer contains a compound represented by the following general formula (A).

[In the formula, Ar represents a substituted or unsubstituted aromatic group, and X represents a carbonyl group or a sulfonyl group. ] A photosensitive layer having a structure in which a charge generation layer and a charge transport layer are laminated on a conductive support, and the charge transport layer contains the compound represented by the general formula (A) and a charge transport material. The electrophotographic photosensitive member according to claim 1, wherein The electrophotographic photoreceptor according to claim 2, wherein the charge transport material is a triarylamine styryl compound represented by the following general formula (B).

[In formula, R < ₁ > -R < ₃ > represents a hydrogen atom, a halogen atom, a C1-C5 alkyl group, and an alkoxy group, respectively. j, n, and m represent an integer of 0 to 3. Ar represents a hydrogen atom or an aryl group which may have a substituent represented by R _{1 to} R ₃ . ] Electrophotographic image formation, wherein the electrophotographic photosensitive member according to any one of claims 1 to 3 is used to form an image through each step of charging, image exposure, development, transfer, separation, and cleaning. apparatus. The electrophotographic photosensitive member according to any one of claims 1 to 3, wherein the electrophotographic photosensitive member is a process cartridge used for image formation through the steps of charging, image exposure, development, transfer, separation, and cleaning. A process cartridge manufactured using a body in combination with at least one selected from a charging device, an image exposure device, a developing device, a transfer or separation device, and a cleaning device.

Images