JP2004101914A - Electrophotographic photoreceptor, and process cartridge and image forming apparatus having the electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having both of mechanical and electric durability and to provide a process cartridge and an image forming apparatus having the above electrophotographic photoreceptor. <P>SOLUTION: The surface protective layer of the electrophotographic photoreceptor contains a polymerization condensation product of an organic silicon-modified hole transfer compound expressed by formula (1) and an alcohol-soluble siloxane resin. In formula (1), A represents a hole transfer group having (a) (represents a number) of aromatic rings, R<SP>1</SP>represents a substituted or unsubstituted organic group, Q represents a hydrolyzable group or hydroxyl group, R<SP>2</SP>represents a substituted or unsubstituted monovalent hydrocarbon group, n represents an integer from 1 to 3, and m represents a positive integer satisfying m/a≥0.5. <P>COPYRIGHT: (C)2004,JPO

Description

（式中、Ａはａ個の芳香環を有する正孔輸送性基を示し、Ｒ^１は置換もしくは無置換の有機基を示し、Ｑは加水分解性基または水酸基を示し、Ｒ^２は置換もしくは無置換の一価炭化水素基を示し、ｎは１〜３の整数を示し、ｍは正の整数を示し、ｍ／ａ≧０．５である。）
で示される有機ケイ素変成正孔輸送性化合物とアルコール可溶性シロキサン樹脂との重縮合生成物を含有することを特徴とする。
【００１３】
また、本発明は、上記電子写真感光体を有するプロセスカートリッジ及び画像形成装置である。
【００１４】
【発明の実施の形態】
本発明では支持体上に感光層を有する電子写真感光体において、該電子写真感光体の表面層が下記式（１）
【００１５】
【化５】

（式中、Ａはａ個の芳香環を有する正孔輸送性基を示し、Ｒ^１は置換もしくは無置換の有機基を示し、Ｑは加水分解性基または水酸基を示し、Ｒ^２は置換もしくは無置換の一価炭化水素基を示し、ｎは１〜３の整数を示し、ｍは正の整数を示し、ｍ／ａ≧０．５である。）
で示される有機ケイ素変成正孔輸送性化合物とアルコール可溶性シロキサン樹脂との重縮合生成物を含有することを特徴とする。
【００１６】
式（１）はクロロシラン類、アルコキシシラン類、シラザン類、ＳｉＨ含有物等であり、Ｑは加水分解性基または水酸基を示し、加水分解性基としては、アルコキシ基、オキシム基、イソシアナト基、ジエチルアミノ基、アセトキシ基、ハロゲン基等が挙げられ、反応性の高さと保存性のバランスにより決定される。
【００１７】
アルコール可溶性シロキサン樹脂は、加水分解性有機ケイ素化合物の加水分解縮合物からなる。その中でも、必須成分として３官能性有機ケイ素を用いたものは、その加水分解縮合を調節することにより硬度が高く且つ製膜性に優れた樹脂が得られるため好適に使用される。すなわち本発明においては、アルコール可溶性シロキサン樹脂として下記一般式（２）
【００１８】
【化６】

（式（２）中、Ｒ^３は炭素数１〜３のアルキル基、ビニル基、フェニル基、Ｃ_ｘＦ_２ｘ＋１Ｃ_２Ｈ_４−（ｘは１〜１８の整数である）、γ−グリシドキシプロピル基またはγ−メタクリロキシプロピル基である。）
で示されるシロキサン樹脂の重縮合生成物を含有することがより好ましい。
【００１９】
本発明における電荷輸送性とは電荷を輸送する能力のことであり、イオン化ポテンシャルで６．２ｅＶ以下であることが好ましい。つまり、式（１）で示される有機ケイ素変性正孔輸送性化合物の重縮合生成物及びＡの水素付加物は、イオン化ポテンシャルが６．２ｅＶ以下であることが好ましく、特に４．５〜６．２ｅＶであることが好ましい。イオン化ポテンシャルが６．２ｅＶを超えると正孔注入が起こりにくく帯電し易くなる。また、４．５ｅＶ未満では化合物が容易に酸化されるために劣化し易くなる。イオン化ポテンシャルは大気下光電子分析法（理研計器製、光電子分光装置ＡＣ−２）によって測定される。
【００２０】
式（１）の正孔輸送性基Ａとしては、正孔輸送性を示すものであればいずれのものでもよく、その水素付加化合物（正孔輸送性有機分子）として示せば、例えばオキサゾール誘導体、オキサジアゾール誘導体、イミダゾール誘導体、トリフェニルアミン等のトリアリールアミン誘導体、９−（ｐ−ジエチルアミノスチリル）アントラセン、１，１−ビス−（４−ジベンジルアミノフェニル）プロパン、スチリルアントラセン、スチリルピラゾリン、フェニルヒドラゾン類、α−フェニルスチルベン誘導体、チアゾール誘導体、トリアゾール誘導体、フェナジン誘導体、アクリジン誘導体、ベンゾフラン誘導体、ベンズイミダゾール誘導体、チオフェン誘導体、Ｎ−フェニルカルバゾール誘導体等が挙げられる。
【００２１】
正孔輸送性基Ａの具体的な構造としては下記式（３）
【００２２】
【化７】

（Ｒ^４、Ｒ^５及びＲ^６は有機基であり、少なくともひとつは芳香族炭化水素環基または芳香族複素環基を含み、Ｒ^４、Ｒ^５及びＲ^６は同一であっても異なっていてもよい。）
で示されるものが好ましい。
【００２３】
このように正孔輸送性基ＡはＲ^４、Ｒ^５及びＲ^６からｍ個の水素原子が除かれて形成された基である。
【００２４】
Ｒ^４、Ｒ^５及びＲ^６の構造の好ましい具体例を以下に示す。
【００２５】
【化８】

【００２６】
【化９】

【００２７】
【化１０】

また、本発明では正孔輸送性基Ａは正孔輸送性を示せばいずれのものでも良いが、式（３）で示され、さらにトリフェニルアミン構造を有するものが好ましい。式（３）で示されるがトリフェニルアミン構造を有していない構造は好ましくない。また、アミノシランなどのシランカップリング剤には市販されているものも多く、式（３）の構造を満たすものが３−アミノプロピルトリメトキシシランなど多く考えられるが、芳香族炭化水素基や芳香族複素環基を多く含まない構造のものは正孔輸送性を示さず、本発明の有機ケイ素変成正孔輸送性化合物とは異なる。
【００２８】
式（１）の有機ケイ素変成正孔輸送性化合物の合成方法としては、公知の方法、例えば、芳香族環にビニル基を有する化合物と置換基を有する水素化ケイ素化合物とから白金系触媒、或いは有機過酸化物等を触媒にヒドロシリル化反応を行うものが好適に用いられる。この場合に使用される白金触媒についてはとくに限定するものではなく、通常のヒドロシリル化反応、付加型シリコーンゴムに用いられている白金触媒であればよく、塩化白金、塩化白金酸、白金−オレフィン錯体、白金−フォスフィン錯体等が挙げられる。白金触媒の添加量に関しては特に制限するものではないが、残留触媒が特性に悪影響を与えないようにできる限り少量で用いることが望ましい。芳香族環にビニル基を有する化合物と置換基を有する水素化ケイ素化合物とから白金系触媒等により、付加反応により本発明の化合物を合成する場合にはビニル基のα位と反応する場合とβ位と反応する場合があり、一般には混合物が生じる。本発明においてはα位、β位のどちらに反応したのものも用いられるが、ケイ素原子と電荷輸送性基を結合している炭化水素基の炭素数が少ない場合には立体障害からはβ位に反応したものが好ましい。
【００２９】
有機過酸化物としては室温以上に半減期を示すものであればよく、特に、ラウリルパーオキシド等のアルキル過酸化物が水素引き抜きを起こしにくいことから好適に用いることができる。ビニル基を有しないものについては、芳香族環をホルミル化し、還元、脱水するか直接ウィッティッヒ（Ｗｉｔｔｉｇ）反応によりビニル基を導入する方法等により、本発明の合成原料として用いることが可能である。
【００３０】
式（１）で示される有機ケイ素変性正孔輸送性化合物の加水分解、重縮合には、必ずしも触媒が必要ではないが、通常ケイ素樹脂等の加水分解、重縮合に用いられる触媒の使用を妨げるものではなく、加水分解、重縮合に要する時間、硬化温度等を考慮してジブチル錫ジアセテート、ジブチル錫ジラウレート、ジブチル錫オクトエート等のアルキル錫有機酸塩等もしくはノルマルブチルチタネート等の有機チタン酸エステル等から適宜選択される。
【００３１】
本発明は、支持体上に電荷発生層、電荷輸送層までを形成した後、式（１）で示される有機ケイ素変成正孔輸送性化合物とアルコールを含有する溶液に浸漬する事によって表面保護層を形成する事を前提としたものである。正孔輸送性化合物は多数の芳香環を含むため、通常はアルコールには溶解しにくいが、我々の検討の結果、有機ケイ素変成によりアルコールへの溶解性が向上する。アルコールへの溶解性は正孔輸送性基Ａに含まれる芳香環の数ａが大きくなるにつれ減少するが、有機ケイ素変成の数ｍとの関係がｍ／ａ≧０．５である場合にアルコールへの十分な溶解性を示す。正孔輸送性基Ａに含まれる芳香環の数ａは正の整数であるが、ａ＝１〜２では正孔輸送性が発現しない場合が多く、ａ＞７ではｍ／ａ≧０．５を満たす場合においてもアルコールへの溶解性が不十分になる傾向があるため好ましくない。したがってａ＝３〜６が最も好ましい範囲である。ａ＝３〜６においてアルコールへの溶解性を十分にするためのケイ素変成の数ｍはｍ／ａ≧０．５を満たすｍ＝２〜３が最低限必要となる。
【００３２】
本発明の正孔輸送能を有する硬化性組成物を用いて電子写真感光体を製造する例を下記に示す。
【００３３】
電子写真感光体の支持体としては支持体自体が導電性を有するもの、例えば、アルミニウム、アルミニウム合金、銅、亜鉛、ステンレススチール、クロム、チタン、ニッケル、マグネシウム、インジウム、金、白金、銀、鉄等を用いることが出来る。その他にアルミニウム、酸化インジウム、酸化スズ、金、等を蒸着等によりプラスチック等の誘電体基材に被膜形成し、導電層としたものや、導電性微粒子をプラスチックや紙に混合したもの等を用いることが出来る。これらの導電性基材は均一な導電性が求められるとともに平滑な表面が重要である。表面の平滑性はその上層に形成される下引き層、電荷発生層、正孔輸送層の均一性に大きな影響を与えることから、その表面荒さは０．３μｍ以下で用いられることが好ましい。０．３μｍ以上の凹凸は下引き層や電荷発生層のような薄い層に印加される局所電場を大きく変化させてしまうためにその特性が大きく変化してしまい電荷注入や残電のむら等の欠陥を生じ易いことから好ましくない。
【００３４】
特に導電性微粒子をポリマーバインダー中に分散して塗布することにより得られる導電層は形成が容易であり、均質な表面を形成することに適している。このとき用いられる導電性微粒子の１次粒径は１００ｎｍ以下であり、より好ましくは５０ｎｍ以下のものが用いられる。導電性微粒子としては、導電性酸化亜鉛、導電性酸化チタン、Ａｌ、Ａｕ、Ｃｕ、Ａｇ、Ｃｏ、Ｎｉ、Ｆｅ、カーボンブラック、ＩＴＯ、酸化スズ、酸化インジウム、インジウム、等が用いられ、これらを絶縁性微粒子の表面にコーティングして用いてもよい。前記導電性微粒子の含有量は体積抵抗が十分に低くなるように使用され、好ましくは１×１０^１０Ωｃｍ以下の抵抗となるように添加される。より好ましくは１×１０^８Ωｃｍ以下で用いられる。
【００３５】
レーザー等のコヒーレントな光源を用いて露光する場合は干渉による画像劣化を防止するために上記導電性基材の表面に凹凸を形成することも可能である。このときは電荷注入や残留電位のむら等の欠陥が生じにくいように使用する波長の１／２λ程度の凹凸を数μｍ以下の直径のシリカビーズ等の絶縁物を分散することに１０μｍ以下の周期で形成して用いることが可能である。
【００３６】
本発明においては、基材と光導電層の中間に、注入阻止機能と接着機能をもつ下引層を設けることもできる。下引き層の材料としてはカゼイン、ポリビニルアルコール、ニトロセルロース、エチレンーアクリル酸コポリマー、ポリビニルブチラール、フェノール樹脂、ポリアミド、ポリウレタン、ゼラチン、等が挙げられる。下引き層の膜厚は０．１μｍ〜１０μｍであることが好ましく、特には０．３μｍ〜３μｍであることが好ましい。
【００３７】
感光層としては電荷発生物質を含有する電荷発生層と電荷輸送物質を含有する電荷輸送層からなる機能分離タイプのものや電荷発生物質と電荷輸送物質を同一の層に含有する単層タイプが用いられる。
【００３８】
機能分離タイプの感光層について説明すると、感光層の構成としては、電荷発生層上に電荷輸送層を積層する構成と、電荷輸送層上に電荷発生層を積層する構成がある。
【００３９】
電荷発生材料としては、例えば、セレン−テルル、ピリリウム系染料、チオピリリウム系染料、フタロシアニン系顔料、アントアントロン系顔料、ジベンズピレンキノン系顔料、ピラントロン系顔料、アゾ系顔料、インジゴ系顔料、キナクリドン系顔料、シアニン系顔料等を用いることができる。これらの電荷発生材料のうち、本発明においては、特にアゾ顔料およびフタロシアニン顔料が適している。フタロシアニン顔料としては、無金属フタロシアニン、銅フタロシアニン、ガリウムフタロシアニン、オキシチタニウムフタロシアニン等が挙げられる。このうち特に長波長光に対して高感度を有するオキシチタニウムフタロシアニンが好ましく、例えば特開昭６１−２３９２４８号公報、特開昭６２−６７０９４号公報、特開平３−１２８９７３号公報及び平３−２００７９０号公報に開示がある。これらの中でも、特開平３−１２８９７３号公報に開示のＣｕＫα特性Ｘ線回折におけるブラッグ角（２θ±０．２°）の９．０°、１４．２°、２３．９°および２７．１°に特徴的なピークを有する結晶形であるオキシチタニウムフタロシアニンがより好ましい。
【００４０】
結着剤としては、広範な絶縁性樹脂から選択でき、例えばポリビニルブチラール、ポリビニルアルコール、ポリアリレート、ポリアミド、アクリル樹脂、ポリ酢酸ビニル、フェノール樹脂、エポキシ樹脂、ポリエステル、ポリカーボネート、ポリウレタン、セルロース系樹脂等の樹脂が挙げられる。電荷発生層中に含有する樹脂は、８０質量％以下、好ましくは５０質量％以下が適している。電荷発生層の厚さは５μｍ以下、特に０．０５〜２μｍであることが好ましい。
【００４１】
本発明の樹脂は電荷輸送層もしくは正孔輸送能を有する表面保護層として用いることが可能である。
【００４２】
本発明における電荷輸送層の膜厚は１〜４０μｍであることが好ましく、特には３〜３０μｍであることが好ましい。本発明における表面保護層の厚みは、１〜１５μｍであることが好ましい。１μｍ以下では保護効果が十分ではなく、１５μｍを越えると感光層全体の膜厚が増加することにより、画像劣化が生じ易くなってしまうことから好ましくない。
【００４３】
光導電層には前記化合物以外にも機械的特性の改良や耐久性向上のために添加剤を用いることができる。このような添加剤としては、酸化防止剤、紫外線吸収剤、安定化剤、架橋剤、潤滑剤、導電性制御剤等が用いられる。
【００４４】
次に、本発明のプロセスカートリッジ並びに電子写真装置について説明する。
【００４５】
図１に本発明のプロセスカートリッジを有する画像形成装置の第１の例の概略構成を示す。
【００４６】
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、軸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、レーザービーム走査露光等の露光手段（不図示）からの露光光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。
【００４７】
形成された静電潜像は、現像手段５によりトナー現像され、現像されたトナー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の回転と同期取り出されて給紙された転写材７に、転写手段６により順次転写されていく。
【００４８】
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（コピー）として装置外にプリントアウトされる。
【００４９】
像転写後の感光体１の表面は、クリーニング手段９によって転写残りトナー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により除電処理された後、繰り返し像形成に使用される。なお、一次帯電手段３が帯電ローラー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。
【００５０】
本発明においては、上述の電子写真感光体１、一次帯電手段３、現像手段５及びクリーニング手段９等の構成要素のうち、複数のものをプロセスカートリッジとして一体に結合して構成し、このプロセスカートリッジを複写機やレーザービームプリンター等の画像形成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２と共に一体に支持してカートリッジ化して、装置本体のレール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ートリッジ１１とすることができる。
【００５１】
また露光光４は、電子写真装置が複写機やプリンターである場合には、原稿からの反射光や透過光、あるいは、センサーで画像を読み取り、信号化し、この信号に従って行われるレーザービームの走査、ＬＥＤアレイの駆動等により照射される光である。
【００５２】
図２に本発明の画像形成装置の第２の例であるカラー複写機の概略構成を示す。
【００５３】
図において２０１はイメージスキャナ部であり、原稿を読み取り、デジタル信号処理を行う部分である。また、２０２はプリンター部であり、イメージスキャナ２０１に読み取られた原稿画像に対応した画像を用紙にフルカラーでプリント出力する部分である。
【００５４】
イメージスキャナ部２０１において、２００は原稿厚板であり、原稿台ガラス２０３上の原稿２０４は赤外カットフィルター２０８を通ったハロゲンランプ２０５の光で照射され、原稿２０４からの反射光はミラー２０６、２０７に導かれ、レンズ２０９により３本のＣＣＤラインセンサ（ＣＣＤ）２１０上に像を結び、フルカラー情報レッド（Ｒ）、グリーン（Ｇ）、ブルー（Ｂ）成分として信号処理部２１１に送られる。なお、２０５、２０６は速度ｖで、２０７は１／２ｖでラインセンサの電気的走査方向（以下、主走査方向という。）に対して垂直方向（以下、副走査方向という。）に機械的に動くことにより、原稿全面を走査する。
【００５５】
信号処理部２１１では読み取られた信号を電気的に処理し、マゼンタ（Ｍ）、シアン（Ｃ）、イエロー（Ｙ）、ブラック（ＢＫ）の各成分に分解し、プリンター部２００に送られ、計４回の原稿走査により一回のプリントアウトが完成する。
【００５６】
イメージスキャナ部２０１より送られてくるＭ，Ｃ，Ｙ，ＢＫの画像信号は、レーザードライバ２１２に送られる。レーザードライバ２１２は画像信号に応じ、半導体レーザー２１３を変調駆動する。レーザー光はポリゴンミラー２１４、ｆ−θレンズ２１５、ミラー２１６を介し、感光体ドラム２１７上を走査する。
【００５７】
２１８は回転現像機であり、マゼンタ現像器２１９、シアン現像器２２０、イエロー現像器２２１、ブラック現像器２２２より構成され、４つの現像器が交互に感光体ドラムに接し、感光体ドラム２１７上に形成されたＭ，Ｃ，Ｙ，ＢＫの静電潜像を対応するトナーで現像する。
【００５８】
２２３は転写ドラムで、用紙カセット２２４または２２５より給紙された用紙をこの転写ドラム２２３に巻付け、感光体ドラム２１７上に現像されたトナー像を用紙に転写する。
【００５９】
このようにしてＭ，Ｃ，Ｙ，ＢＫの４色が順次転写された後に、用紙は定着ユニット２２６を通過して定着後、排紙される。
【００６０】
【実施例】
以下、実施例によって本発明を説明する。式（１）で表される有機ケイ素変性正孔輸送性化合物は、例えば以下のようにして合成した。
【００６１】
［合成例１］
４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミンの合成
〈４−メチル−トリフェニルアミンの合成〉
ヨードベンゼン３３．９ｇ（１６６ｍｍｏｌ）、無水炭酸カリウム２２．９ｇ（１６６ｍｍｏｌ）及び銅粉７．０ｇを４−ニトロトルエン２０ｍｌに加え、撹拌下加熱環流を８時間行った。冷却後濾過し、濾液を除去した。得られた反応混合物はシリカゲルカラムを通し４−メチル−トリフェニルアミンを得た。収量１３．５ｇ。
【００６２】
〈４，４’−ジホルミル−４’’−メチル−トリフェニルアミンの合成〉
三つ口フラスコに４−メチル−トリフェニルアミン５３．６ｇ、ＤＭＦ３５．５ｍｌを入れ、氷水冷却下、撹拌しながらオキシ塩化リン８４．４ｍｌを滴下した。滴下終了後、混合溶液を９５℃で５時間反応させ、４ｌの温水へ注ぎ１時間撹拌した。その後、沈殿物をロ取し、エタノール／水（１：１）の混合溶液で洗浄し、４，４’−ジホルミル−４’’−メチル−トリフェニルアミンを得た。収量５１．５ｇ。
【００６３】
〈４，４’−ジビニル−４’’−メチル−トリフェニルアミンの合成〉
水素化ナトリウム１２．１ｇ、１，２−ジメトキシエタン５８０ｍｌを三つ口フラスコに取り、室温で撹拌しながらトリメチルホスフォニウムブロマイド１０８．５ｇを加えた。次に無水エタノールを一滴加えた後、７０℃で４時間反応させた。以上のようにして得られた反応混合液に４，４’−ジホルミル−４’’−メチル−トリフェニルアミン４７．９ｇを加え、７０℃で５時間反応させた後、ロ別し、ロ取したケーキをエーテル抽出しロ液と一緒しにし水洗した。ついで、エーテル液を塩化カルシウムで脱水後、エーテルを除去し、反応混合物を得た。これをエタノールで再結晶二回行い、針状の４，４’−ジビニル−４’’−メチル−トリフェニルアミンを得た。収量４０．２ｇ。
【００６４】
〈４，４’−ジビニル−４’’−メチル−トリフェニルアミンのヒドロシリル化〉
トルエン４０ｍｌ、メチルジメトキシシラン３．８４ｇ及びトリス（テトラメチルジビニルジシロキサン）二白金（０）のトルエン溶液０．５４ｍｍｏｌを三つ口フラスコに取り、室温で撹拌しながら４，４’−ジビニル−４’’−メチル−トリフェニルアミン４．７１ｇのトルエン溶液２０ｍｌを滴下した。滴下終了後、７０℃で３時間撹拌を行った後、溶媒を減圧下で除去し、淡黄色油状の４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミンを得た。収量６．７６ｇ。
【００６５】
合成した４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミン８．０ｇをイソプロパノール１２．０ｇに溶解したところ、均一で透明な溶液となった。
【００６６】
この溶液を銅基板上にワイヤーバーコート法により塗布し、１２０℃にて１２時間熱硬化し、約５μｍの膜を作成した。次に蒸着により半透明金電極を形成した。
【００６７】
このサンプルに対してパルス巾３ｎｓｅｃの波長３３７ｎｍの窒素レーザーを用いてＴｉｍｅ−ｏｆ−ｆｌｉｇｈｔ法にてドリフト移動度を測定したところ９×１０^−７ｃｍ^２／Ｖｓｅｃであった。
【００６８】
［合成例２］
４，４’−ビス［２−（トリエトキシシリル）エチル］−３’’，４’’−ジメチル−トリフェニルアミンの合成
〈３，４−ジメチル−トリフェニルアミンの合成〉
ヨードベンゼン３３．９ｇ（１６６ｍｍｏｌ）、無水炭酸カリウム２２．９ｇ（１６６ｍｍｏｌ）及び銅粉７．０ｇを４−ニトロ−ｏ−キシレン２５ｍｌに加え、撹拌下加熱環流を８時間行った。冷却後濾過し、濾液を除去した。得られた反応混合物をシリカゲルカラムを通し３，４−ジメチル−トリフェニルアミンを得た。収量１４．２ｇ。
【００６９】
〈４，４’−ジホルミル−３’’，４’’−ジメチル−トリフェニルアミンの合成〉
三つ口フラスコに３，４−ジメチル−トリフェニルアミン５６．５ｇ、ＤＭＦ３５．５ｍｌを入れ、氷水冷却下、撹拌しながらオキシ塩化リン８４．４ｍｌを滴下した。滴下終了後、混合溶液を９５℃で５時間反応させ、４ｌの温水へ注ぎ１時間撹拌した。その後、沈殿物をロ取し、エタノール／水（１：１）の混合溶液で洗浄し、４，４’−ジホルミル−３’’，４’’−ジメチル−トリフェニルアミンを得た。収量５３．８ｇ。
【００７０】
〈４，４’−ジビニル−３’’，４’’−ジメチル−トリフェニルアミンの合成〉
水素化ナトリウム１２．１ｇ、１，２−ジメトキシエタン５８０ｍｌを三つ口フラスコに取り、室温で撹拌しながらトリメチルホスフォニウムブロマイド１０８．５ｇを加えた。次に無水エタノールを一滴加えた後、７０℃で４時間反応させた。以上のようにして得られた反応混合液に４，４’−ジホルミル−３’’，４’’−ジメチル−トリフェニルアミン５０．１ｇを加え、７０℃で５時間反応させた後、ロ別し、ロ取したケーキをエーテル抽出しロ液と一緒しにし水洗した。ついで、エーテル液を塩化カルシウムで脱水後、エーテルを除去し、反応混合物を得た。これをエタノールで再結晶二回行い、針状、４，４’−ジビニル−３’’，４’’−ジメチル−トリフェニルアミンを得た。収量４２．０ｇ。
【００７１】
〈４，４’−ジビニル−３’’，４’’−ジメチル−トリフェニルアミンのヒドロシリル化〉
トルエン４０ｍｌ、トリエトキシシラン６．０ｇ及びトリス（テトラメチルジビニルジシロキサン）二白金（０）のトルエン溶液０．５４ｍｍｏｌを三つ口フラスコに取り、室温で撹拌しながら４，４’−ジビニル−３’’，４’’−ジメチル−トリフェニルアミン４．９２ｇのトルエン溶液２０ｍｌを滴下した。滴下終了後、７０℃で３時間撹拌を行った後、溶媒を減圧下で除去し、淡黄色油状の４，４’−ビス［２−（トリエトキシシリル）エチル］−３’’，４’’−ジメチル−トリフェニルアミンを得た。収量７．５０ｇ。
【００７２】
合成した４，４’−ビス［２−（トリエトキシシリル）エチル］−３’’，４’’−ジメチル−トリフェニルアミン８．０ｇをイソプロパノール１２．０ｇに溶解したところ、均一で透明な溶液となった。
【００７３】
以下、実施例を挙げ本発明を更に詳細に説明する。なお、実施例中の「部」は重量部を示す。
【００７４】
［実施例１］
引き抜き加工により得られた外径３０ｍｍのアルミニウムシリンダー上に、フェノール樹脂（商品名：プライオーフェン、大日本インキ化学工業（株）製）１６７部をメチルセロソルブ１００部に溶解したものへ導電性硫酸バリウム超微粒子（１次粒径５０ｎｍ）２００部及び平均粒径２μｍのシリコーン樹脂粒子３部を分散したものを浸せきコーティング法により塗工し、乾燥後の膜厚が１５μｍの導電層を形成した。
【００７５】
上記導電層上にアルコール可溶性共重合ナイロン（商品名：アミランＣＭ−８０００、東レ（株）製）５部をメタノール９５部に溶解した溶液を浸せきコーティング法により塗工した。８０℃で１０分間乾燥して、膜厚が０．５μｍの下引き層を形成した。
【００７６】
次に、電荷発生層用分散液としてＣｕＫα特性Ｘ線回折におけるブラッグ角（２θ±０．２゜）の９．０゜、１４．２゜、２３．９゜及び２７．９゜に強いピークを有するオキシチタニルフタロシアニン顔料５部をシクロヘキサノン９５部にポリビニルベンザール（ベンザール化度７５％以上）２部を溶解した液に加え、サンドミルで２時間分散した。
【００７７】
この分散液を先に形成した下引き層の上に乾燥後の膜厚が０．２μｍとなるように浸せきコーティング法で塗工した。
【００７８】
次に、下記の構造式を有するトリアリールアミン化合物９部とポリカーボネート樹脂（商品名：Ｚ−２００、三菱瓦斯化学（株）製）１０部をクロロベンゼン７０部に溶解した。この液を前記の電荷発生層上に浸せきコーティング法により塗布し、乾燥後１２μｍの電荷輸送層を設けた。
【００７９】
【化１１】

次に、メチルトリエトキシシラン４５部に、撹拌しながらイソプロピルアルコール３０部、水１８部、酢酸１部を添加した。添加後、混合溶液を６０℃まで加熱し、２時間反応させた。その後、イソプロピルアルコール３０部で反応溶液を希釈して、４８時間撹拌した。この液に、合成例１で合成した４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミン１７部とイソプロパノール５７部とジブチル錫ジラウレート１部を添加した。
【００８０】
この調合液を、上記電荷輸送層上に浸積コーティング法により塗布し、乾燥後３μｍの表面層を得た。
【００８１】
この電子写真感光体を−６００Ｖに帯電し、波長６８０ｎｍの光を用いて電子写真特性を測定したところ、Ｅ_１／２（−３００Ｖまで帯電電位が減少するために必要な露光量）が０．２３Ｊ／ｃｍ^２、残留電位が−６０Ｖと良好であった。
【００８２】
本電子写真感光体をキヤノン製レーザービームプリンターＬＢＰ−ＳＸの改造機（（１／ｅ２）を副走査方向で６３．５μｍ、主走査方向で２０μｍの照射スポット径となるように改造した）を用い初期帯電−６００Ｖに設定して画像評価をおこなったところ、５０００枚の耐久試験後においても画像の劣化がなく、６００ｄｐｉ相当の入力信号においてのハイライト部の１画素再現性も十分であった。
【００８３】
［比較例１］
実施例１と同様にして、電荷輸送層まで形成した。次に、合成例１で合成した４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミンを、特開平９−１９００４の合成例５に記載の方法で合成した４−［２−（トリエトキシシリル）エチル］−トリフェニルアミンに変えた以外は実施例１と同様にして表面層用の塗工液を調液したが、液は白濁していた。
【００８４】
この調合液を、上記電荷輸送層上に浸積コーティング法により塗布し、乾燥したところ、多数のブツが発生し、表面性の良好な膜は得られなかった。
【００８５】
［実施例２］
実施例１と同様のアルミニウムシリンダー上に、フェノール樹脂（商品名：プライオーフェン、大日本インキ化学工業（株）製）１６７部をメチルセロソルブ１００部に溶解したものへ導電性硫酸バリウム超微粒子（１次粒径５０ｎｍ）２００部を分散したものを浸せきコーティング法により、乾燥後の膜厚が１０μｍとなるように塗工した。この導電性支持体に実施例２と同様にして膜厚１μｍの下引き層、膜厚０．２μｍの電荷発生層および膜厚１２μｍの電荷輸送層を形成した。
【００８６】
次に、メチルトリエトキシシラン４５部に、撹拌しながらイソプロピルアルコール３０部、水１８部、酢酸１部を添加した。添加後、混合溶液を６０℃まで加熱し、２時間反応させた。その後、イソプロピルアルコール３０部で反応溶液を希釈して、４８時間撹拌した。この液に、合成例２で合成した４，４’−ビス［２−（トリエトキシシリル）エチル］−３’’，４’’−ジメチル−トリフェニルアミン１７部とイソプロパノール５７部とジブチル錫ジラウレート１部を添加した。
【００８７】
この調合液を、上記電荷輸送層上に浸積コーティング法により塗布し、乾燥後３μｍの表面層を得た。
【００８８】
この電子写真感光体を−６００Ｖに帯電し、波長６８０ｎｍの光を用いて電子写真特性を測定したところ、Ｅ_１／２（−３００Ｖまで帯電電位が減少するために必要な露光量）が０．２２Ｊ／ｃｍ^２、残留電位が−５７Ｖと非常に良好であった。
【００８９】
本電子写真感光体を実施例２と同様のキヤノン製レーザービームプリンターを用い初期帯電−５００Ｖに設定して画像評価をおこなったところ、５０００枚の耐久試験後においても画像の劣化がなく、６００ｄｐｉ相当の入力信号においてのハイライト部の１画素再現性も十分であった。
【００９０】
［比較例２］
実施例１と同様にして、電荷発生層まで形成した。次いで、下記のトリアリールアミン化合物６部と、
【００９１】
【化１２】

ポリカーボネート樹脂（商品名：Ｚ２００、三菱瓦斯化学（株）製）６部をクロロベンゼン７０部に溶解した電荷輸送層用の液を実施例２の電荷発生層の上に浸漬コーティング法により塗工することによって、乾燥後の膜厚が２０μｍの電荷輸送層を形成した。この電子写真感光体を−６００Ｖに帯電し、波長６８０ｎｍの光を用いて電子写真特性を測定したところ、Ｅ_１／２（−３００Ｖまで帯電電位が減少するために必要な露光量）が０．３８Ｊ／ｃｍ^２、残留電位が−１２０Ｖと大きかった。
【００９２】
本電子写真感光体をキヤノン製レーザービームプリンターＬＢＰ−ＳＸの改造機（（１／ｅ２）を副走査方向で６３．５μｍ、主走査方向で４０μｍの照射スポット径となるように改造した）を用い初期帯電−６００Ｖに設定して画像評価をおこなったところ、４０００枚の耐久試験後は干渉縞および黒ポチが認められ、６００ｄｐｉ相当の入力信号においてのハイライト部の１画素再現性も不十分でむらがあった。
【００９３】
［実施例３］
外径８０ｍｍのアルミニウムシリンダー上に、１０％の酸化アンチモンを含有する酸化錫で被覆した導電性酸化チタン粉末５０部、フェノール樹脂２５部、メチルセロソルブ３０部、メタノール３０部およびシリコーンオイル（ポリメチルシロキサンポリオキシアルキレン共重合体、重量平均分子量３０００）０．００２部を１φｍｍガラスビーズ入りサンドミル装置で２時間分散して調整した導電層用塗料を浸漬塗布し、１４０℃で３０分間乾燥して膜厚２０μｍの導電層を形成した。
【００９４】
次にアルコール可溶性共重合ナイロン（商品名：アミランＣＭ−８０００、東レ（株）製）５部をメタノール９５部に溶解した溶液を浸せきコーティング法により塗工した。８０℃で１０分間乾燥して、膜厚が１μｍの下引き層を形成した。
【００９５】
次に、電荷発生層として下記のビスアゾ顔料５部をシクロヘキサノン９５部にポリビニルベンザール（ベンザール化度７５％以上）２部を溶解した液に加え、サンドミルで２０時間分散した。この分散液を先に形成した下引き層の上に乾燥後の膜厚が０．２μｍとなるように浸せきコーティング法で塗工した。
【００９６】
【化１３】

次に、下記の構造式を有するトリアリールアミン化合物７部とポリカーボネート樹脂（商品名：Ｚ−２００、三菱瓦斯化学（株）製）１０部をクロロベンゼン７０部に溶解した。この液を前記の電荷発生層上に浸せきコーティング法により塗布し、乾燥後１２μｍの電荷輸送層を設けた。
【００９７】
【化１４】

次に、メチルトリエトキシシラン４０部と３，３，４，４，５，５，６，６，６−ノナフルオロヘキシルトリエトキシシラン９部に、撹拌しながらイソプロピルアルコール３０部、水１８部、酢酸１部を添加した。添加後、混合溶液を６０℃まで加熱し、２時間反応させた。その後、イソプロピルアルコール３０部で反応溶液を希釈して、４８時間撹拌した。この液に、合成例１で合成した４，４’−ビス［２−（メチルジメトキシシリル）エチル］−４’’−メチル−トリフェニルアミン２２部とイソプロパノール７４部とジブチル錫ジラウレート１部を添加した。
【００９８】
この調合液を、上記電荷輸送層上に浸積コーティング法により塗布し、乾燥後３μｍの表面層を得た。
【００９９】
この電子写真感光体を−７００Ｖに帯電し、波長６８０ｎｍの光を用いて電子写真特性を測定したところ、Ｅ_１／２（−３５０Ｖまで帯電電位が減少するために必要な露光量）が０．８１μＪ／ｃｍ^２、残留電位が−３２Ｖと良好であった。
【０１００】
本電子写真感光体を用いて、キヤノン製デジタルフルカラー複写機ＣＬＣ−５００を副走査方向で６３．５μｍ、主走査方向で２０μｍの照射スポット径となるように改造した評価機にて初期帯電−７００Ｖに設定して画像評価をおこなったところ、初期及び１０万枚耐久試験後も黒ポチ等の電荷注入および干渉縞もなく、均一性の優れた画像出力が得られ、階調再現性も４００ｄｐｉで２５６階調と極めて良好であった。
【０１０１】
【発明の効果】
表面の耐久性があり光散乱やブリードがなく、感度の低下や残留電位の上昇などの電気的特性の悪化を招かない機械的、電気的耐久性を両立した電子写真感光体、及び該電子写真感光体を有するプロセスカートリッジ及び画像形成装置を提供できる。
【図面の簡単な説明】
【図１】本発明の画像形成装置の第１の例の概略構成を示す図である。
【図２】本発明の画像形成装置の第２の例の概略構成を示す図である。
【符号の説明】
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　クリーニング手段
１０　前露光光
１１　プロセスカートリッジ
１２　レール
２００　原稿厚板
２０１　イメージスキャナ部
２０２　プリンター部
２０３　原稿台ガラス
２０４　原稿
２０５　ハロゲンランプ
２０６，２０７　ミラー
２０８　赤外カットフィルター
２０９　レンズ
２１０　３ラインセンサ
２１１　信号処理部
２１２　レーザードライバ
２１３　半導体レーザー
２１４　ポリゴンミラー
２１５　ｆ−θレンズ
２１６　ミラー
２１７　感光体ドラム
２１８　回転現像機
２１９　マゼンタ現像機
２２０　シアン現像機
２２１　イエロー現像機
２２２　ブラック現像機
２２３　転写ドラム
２２４，２２５　用紙カセット
２２６　定着ユニット[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrophotographic photosensitive member having a surface protective layer having a specific composition, a process cartridge having the electrophotographic photosensitive member, and an image forming apparatus.
[0002]
[Prior art]
The surface layer of the electrophotographic photoreceptor is required to have durability against electric or mechanical influences because it is directly subjected to electrical or mechanical influence by a charging means, a developing means, a transferring means, a cleaning means and the like. Specifically, durability against abrasion and scratches on the surface of the photoreceptor due to rubbing and deterioration of the surface of the photoreceptor due to corona charging are required. In addition, there is a problem that toner adheres to the surface of the photoconductor due to repetition of development and cleaning. For this purpose, improvement of the cleaning property of the surface of the photoconductor is required. Further, there is also a demand for electrical characteristics that do not cause deterioration such as a decrease in sensitivity and an increase in residual potential.
[0003]
Attempts have been made to provide various surface protective layers containing a resin as a main component on the charge generation layer or the charge transport layer in order to satisfy the various characteristics required for the photoreceptor surface as described above. For example, JP-A-57-30843 proposes a protective layer in which resistance is controlled by adding metal oxide particles as conductive particles.
[0004]
It has also been studied to improve the physical properties of the photoreceptor surface by adding various substances to the surface layer. For example, additives focused on low surface energy of silicone include silicone oil (JP-A-61-132954), polydimethylsiloxane, silicone resin powder (JP-A-4-324454), cross-linked silicone resin, (Polycarbonate-silicon) block copolymers, modified silicone polyurethanes, modified silicone polyesters, and colloidal silica-containing silicone resins have been reported. A typical polymer having a low surface energy is a fluoropolymer, and examples of the fluoropolymer include polytetrafluoroethylene powder and carbon fluoride powder.
[0005]
As described above, in addition to the surface layer in which the hole transporting organic molecules are dispersed in the resin binder component, a surface protective layer in which various substances such as metal oxide particles are dispersed in order to improve the electrical characteristics, and the charge transporting. Although a layer has been proposed, since the ordinary binder resin component does not have a hole transporting ability, when the content of the binder resin is increased, the deterioration of the electrical characteristics such as a decrease in sensitivity or an increase in the residual potential is caused. There was a problem that it was easy to invite.
[0006]
Although a surface protective layer containing a metal oxide or the like having high hardness and charge transport ability can be obtained, there is a problem that an image is easily blurred due to low surface resistance.
[0007]
As a method for improving the above-listed problems, a surface layer containing a resin obtained by curing a curable organosilicon polymer and an organosilicon-modified hole transporting compound in JP-A-9-19004 is disclosed. A photoconductor is proposed. However, the organosilicon-modified hole transporting compound has low solubility in alcohol, and the use of organic solvents such as aromatics, ethers, esters, and ketones was necessary to obtain a sufficient coating solution concentration for dip coating. . Therefore, there is a problem that the curable organosilicon polymer that can be used in combination is also limited to the above-mentioned solvent system. That is, for example, when it is attempted to formulate a coating solution by the method described in Example 8 of JP-A-2000-310870, the organosilicon-modified hole transporting property tends to precipitate, and the formed surface layer becomes cloudy. However, there is a problem that image deterioration is caused.
[0008]
Therefore, as a result of intensive studies, when m / a ≧ 0.5 in the formula (1), the solubility of the modified organosilicon hole transporting compound in alcohol is increased, and the photoreceptor is dissolved together with the alcohol-soluble siloxane resin. The present inventors have found that dip coating can be performed on the surface layer, and have reached the present invention.
[0009]
[Problems to be solved by the invention]
An object of the present invention is to solve the above-mentioned problems, that is, a machine that has a durable surface and does not cause light scattering or bleeding, and does not cause deterioration in electrical characteristics such as a decrease in sensitivity or an increase in residual potential. An object of the present invention is to provide an electrophotographic photoreceptor having both high electrical and electrical durability, and a process cartridge and an image forming apparatus having the electrophotographic photoreceptor.
[0010]
[Means for Solving the Problems]
The present invention is based on the premise that a photoreceptor surface layer is formed by dissolving an organosilicon-modified hole transporting compound represented by the formula (1) and a siloxane resin in an alcohol-containing solution and dip-coating the solution. is there. Since the hole transporting compound contains a large number of aromatic rings, it is usually difficult to dissolve in alcohol, but as a result of our study, the solubility in alcohol is improved by organosilicon modification. The solubility in alcohol decreases as the number a of the aromatic rings contained in the hole transporting group A increases, but when the relationship with the number m of the organosilicon modification is m / a ≧ 0.5, the alcohol solubility is reduced. The present invention has been found to show that the surface protective layer can be dip-coated without dissolving the charge transport layer without using the organic solvent as described above.
[0011]
That is, the present invention provides an electrophotographic photosensitive member having a photosensitive layer on a support, wherein the surface layer of the electrophotographic photosensitive member has the following formula (1)
[0012]
Embedded image

(Wherein, A represents a hole transporting group having a number of aromatic rings, ¹ Represents a substituted or unsubstituted organic group; Q represents a hydrolyzable group or a hydroxyl group; ² Represents a substituted or unsubstituted monovalent hydrocarbon group, n represents an integer of 1 to 3, m represents a positive integer, and m / a ≧ 0.5. )
Wherein a polycondensation product of an organosilicon-modified hole-transporting compound represented by and an alcohol-soluble siloxane resin is contained.
[0013]
Further, the present invention is a process cartridge and an image forming apparatus having the above electrophotographic photosensitive member.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, in an electrophotographic photosensitive member having a photosensitive layer on a support, the surface layer of the electrophotographic photosensitive member has the following formula (1)
[0015]
Embedded image

(Wherein, A represents a hole transporting group having a number of aromatic rings, ¹ Represents a substituted or unsubstituted organic group; Q represents a hydrolyzable group or a hydroxyl group; ² Represents a substituted or unsubstituted monovalent hydrocarbon group, n represents an integer of 1 to 3, m represents a positive integer, and m / a ≧ 0.5. )
Wherein a polycondensation product of an organosilicon-modified hole-transporting compound represented by and an alcohol-soluble siloxane resin is contained.
[0016]
Formula (1) represents chlorosilanes, alkoxysilanes, silazanes, SiH-containing substances, and the like, Q represents a hydrolyzable group or a hydroxyl group, and the hydrolyzable groups include an alkoxy group, an oxime group, an isocyanato group, and a diethylamino group. Groups, an acetoxy group, a halogen group and the like, and are determined by a balance between high reactivity and storage stability.
[0017]
The alcohol-soluble siloxane resin comprises a hydrolyzed condensate of a hydrolyzable organosilicon compound. Among them, those using trifunctional organosilicon as an essential component are preferably used because a resin having high hardness and excellent film-forming properties can be obtained by controlling the hydrolysis and condensation. That is, in the present invention, an alcohol-soluble siloxane resin represented by the following general formula (2)
[0018]
Embedded image

(In the formula (2), R ³ Is an alkyl group having 1 to 3 carbon atoms, a vinyl group, a phenyl group, C _x F _{2x + 1} C ₂ H ₄ — (X is an integer of 1 to 18), γ-glycidoxypropyl group or γ-methacryloxypropyl group. )
It is more preferable to contain a polycondensation product of a siloxane resin represented by
[0019]
The charge transporting property in the present invention refers to the ability to transport charges, and preferably has an ionization potential of 6.2 eV or less. That is, the polycondensation product of the organosilicon-modified hole transporting compound represented by the formula (1) and the hydrogenated product of A preferably have an ionization potential of 6.2 eV or less, and particularly preferably have an ionization potential of 4.5 to 6.5. It is preferably 2 eV. If the ionization potential exceeds 6.2 eV, hole injection is unlikely to occur and charging is likely to occur. If it is less than 4.5 eV, the compound is easily oxidized and thus easily deteriorates. The ionization potential is measured by a photoelectron spectrometry under the atmosphere (manufactured by Riken Keiki, photoelectron spectrometer AC-2).
[0020]
As the hole transporting group A of the formula (1), any one having a hole transporting property may be used, and as a hydrogenated compound (hole transporting organic molecule), for example, an oxazole derivative, Oxadiazole derivatives, imidazole derivatives, triarylamine derivatives such as triphenylamine, 9- (p-diethylaminostyryl) anthracene, 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline Phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, N-phenylcarbazole derivatives and the like.
[0021]
The specific structure of the hole transporting group A is represented by the following formula (3)
[0022]
Embedded image

(R ⁴ , R ⁵ And R ⁶ Is an organic group, at least one of which contains an aromatic hydrocarbon ring group or an aromatic heterocyclic group, ⁴ , R ⁵ And R ⁶ May be the same or different. )
Are preferred.
[0023]
Thus, the hole transporting group A is R ⁴ , R ⁵ And R ⁶ Is a group formed by removing m hydrogen atoms from
[0024]
R ⁴ , R ⁵ And R ⁶ Preferred examples of the structure are shown below.
[0025]
Embedded image

[0026]
Embedded image

[0027]
Embedded image

Further, in the present invention, the hole transporting group A may be any one as long as it exhibits a hole transporting property, but is preferably one represented by the formula (3) and further having a triphenylamine structure. A structure represented by the formula (3) but having no triphenylamine structure is not preferable. In addition, many silane coupling agents such as aminosilane are commercially available, and those satisfying the structure of the formula (3) are considered to be many such as 3-aminopropyltrimethoxysilane. Those having a structure not containing a large amount of heterocyclic groups do not show a hole transporting property, which is different from the modified organosilicon hole transporting compound of the present invention.
[0028]
As a method for synthesizing the organosilicon-modified hole-transporting compound of the formula (1), a known method, for example, a platinum-based catalyst or a silicon hydride compound having a substituent and a vinyl group on an aromatic ring is used. Those that perform a hydrosilylation reaction using an organic peroxide or the like as a catalyst are suitably used. The platinum catalyst used in this case is not particularly limited, and may be any platinum catalyst used in ordinary hydrosilylation reactions and addition-type silicone rubbers, such as platinum chloride, chloroplatinic acid, and platinum-olefin complexes. , A platinum-phosphine complex and the like. The amount of the platinum catalyst to be added is not particularly limited, but it is preferable to use the platinum catalyst in the smallest possible amount so as not to adversely affect the characteristics of the catalyst. When a compound of the present invention is synthesized by an addition reaction from a compound having a vinyl group on an aromatic ring and a silicon hydride compound having a substituent with a platinum-based catalyst or the like, when the compound reacts with the α-position of the vinyl group, May form a mixture. In the present invention, those reacting at either the α-position or the β-position may be used. However, when the number of carbon atoms in the hydrocarbon group bonding the silicon atom and the charge transporting group is small, the β-position may be sterically hindered. Are preferred.
[0029]
Any organic peroxides having a half-life at room temperature or higher may be used. In particular, alkyl peroxides such as lauryl peroxide can be suitably used because hydrogen extraction hardly occurs. Those having no vinyl group can be used as a raw material for synthesis of the present invention by, for example, a method in which an aromatic ring is formylated, reduced and dehydrated, or a method of directly introducing a vinyl group by a Wittig reaction.
[0030]
A catalyst is not necessarily required for the hydrolysis and polycondensation of the organosilicon-modified hole transporting compound represented by the formula (1), but it hinders the use of a catalyst usually used for hydrolysis or polycondensation of a silicon resin or the like. Instead of taking into account the time required for hydrolysis and polycondensation, the curing temperature, etc., alkyl tin organic acid salts such as dibutyltin diacetate, dibutyltin dilaurate, and dibutyltin octoate, or organic titanates such as normal butyl titanate Etc. are appropriately selected.
[0031]
According to the present invention, the surface protective layer is formed by forming a charge generation layer and a charge transport layer on a support and then immersing the layer in a solution containing an organosilicon-modified hole transport compound represented by the formula (1) and an alcohol. Is assumed to be formed. Since the hole transporting compound contains a large number of aromatic rings, it is usually difficult to dissolve in alcohol, but as a result of our study, the solubility in alcohol is improved by organosilicon modification. The solubility in alcohol decreases as the number a of the aromatic rings contained in the hole transporting group A increases, but when the relationship with the number m of the organosilicon modification is m / a ≧ 0.5, the alcohol solubility is reduced. Shows sufficient solubility in The number a of the aromatic rings contained in the hole transporting group A is a positive integer. In many cases, the hole transporting property does not appear when a = 1 to 2, and when a> 7, m / a ≧ 0.5. Is not preferable because the solubility in alcohol tends to be insufficient. Therefore, a = 3 to 6 is the most preferable range. In the case of a = 3 to 6, the number m of the silicon modification for ensuring sufficient solubility in alcohol must be at least m = 2 to 3 satisfying m / a ≧ 0.5.
[0032]
An example of producing an electrophotographic photosensitive member using the curable composition having a hole transporting ability of the present invention will be described below.
[0033]
As the support of the electrophotographic photosensitive member, the support itself has conductivity, for example, aluminum, aluminum alloy, copper, zinc, stainless steel, chromium, titanium, nickel, magnesium, indium, gold, platinum, silver, iron Etc. can be used. In addition, aluminum, indium oxide, tin oxide, gold, etc. are used to form a conductive layer by forming a film on a dielectric substrate such as plastic by vapor deposition or the like, or a mixture of conductive fine particles in plastic or paper is used. I can do it. For these conductive substrates, uniform conductivity is required and a smooth surface is important. Since the surface smoothness greatly affects the uniformity of the undercoat layer, charge generation layer and hole transport layer formed thereon, the surface roughness is preferably used at 0.3 μm or less. The unevenness of 0.3 μm or more greatly changes the local electric field applied to a thin layer such as an undercoat layer or a charge generation layer, and the characteristics thereof are greatly changed, resulting in defects such as charge injection and uneven remaining charge. This is not preferred because it tends to cause
[0034]
In particular, a conductive layer obtained by dispersing and applying conductive fine particles in a polymer binder is easy to form and is suitable for forming a uniform surface. The primary particle size of the conductive fine particles used at this time is 100 nm or less, and more preferably 50 nm or less. As the conductive fine particles, conductive zinc oxide, conductive titanium oxide, Al, Au, Cu, Ag, Co, Ni, Fe, carbon black, ITO, tin oxide, indium oxide, indium, and the like are used. The surface of the insulating fine particles may be coated before use. The content of the conductive fine particles is used so that the volume resistance is sufficiently low. ¹⁰ It is added so as to have a resistance of Ωcm or less. More preferably 1 × 10 ⁸ It is used below Ωcm.
[0035]
When exposure is performed using a coherent light source such as a laser, it is possible to form irregularities on the surface of the conductive substrate in order to prevent image deterioration due to interference. In this case, irregularities of about 1 / 2λ of the wavelength used to disperse insulators such as silica beads having a diameter of several μm or less in a period of 10 μm or less so that defects such as charge injection and residual potential unevenness do not easily occur. It can be formed and used.
[0036]
In the present invention, an undercoat layer having an injection blocking function and an adhesion function may be provided between the base material and the photoconductive layer. Examples of the material of the undercoat layer include casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, polyamide, polyurethane, and gelatin. The thickness of the undercoat layer is preferably from 0.1 μm to 10 μm, particularly preferably from 0.3 μm to 3 μm.
[0037]
As the photosensitive layer, a function separation type including a charge generation layer containing a charge generation substance and a charge transport layer containing a charge transport substance, and a single layer type containing the charge generation substance and the charge transport substance in the same layer are used. Can be
[0038]
The function-separated type photosensitive layer will be described. The photosensitive layer has a configuration in which a charge transport layer is laminated on a charge generation layer and a configuration in which a charge generation layer is laminated on a charge transport layer.
[0039]
Examples of the charge generation material include selenium-tellurium, pyrylium dyes, thiopyrylium dyes, phthalocyanine pigments, anthantrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, azo pigments, indigo pigments, and quinacridone pigments. Pigments, cyanine-based pigments, and the like can be used. Among these charge generating materials, in the present invention, azo pigments and phthalocyanine pigments are particularly suitable. Examples of the phthalocyanine pigment include metal-free phthalocyanine, copper phthalocyanine, gallium phthalocyanine, and oxytitanium phthalocyanine. Of these, oxytitanium phthalocyanine having high sensitivity to long-wavelength light is particularly preferable. For example, JP-A-61-239248, JP-A-62-67094, JP-A-3-128973 and JP-A-3-200790. There is a disclosure in Japanese Patent Publication No. Among these, 9.0 °, 14.2 °, 23.9 ° and 27.1 ° of the Bragg angles (2θ ± 0.2 °) in the CuKα characteristic X-ray diffraction disclosed in Japanese Patent Application Laid-Open No. 3-128973. Oxytitanium phthalocyanine, which is a crystalline form having a peak characteristic of
[0040]
The binder can be selected from a wide range of insulating resins, for example, polyvinyl butyral, polyvinyl alcohol, polyarylate, polyamide, acrylic resin, polyvinyl acetate, phenol resin, epoxy resin, polyester, polycarbonate, polyurethane, cellulose resin, and the like. Resins. The amount of the resin contained in the charge generation layer is at most 80% by mass, preferably at most 50% by mass. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.05 to 2 μm.
[0041]
The resin of the present invention can be used as a charge transporting layer or a surface protective layer having a hole transporting ability.
[0042]
The thickness of the charge transport layer in the invention is preferably from 1 to 40 μm, and particularly preferably from 3 to 30 μm. The thickness of the surface protective layer in the present invention is preferably from 1 to 15 μm. If the thickness is 1 μm or less, the protective effect is not sufficient, and if it exceeds 15 μm, the film thickness of the entire photosensitive layer increases, which is not preferable since image deterioration is likely to occur.
[0043]
Additives other than the above compounds can be used in the photoconductive layer in order to improve mechanical properties and durability. As such additives, antioxidants, ultraviolet absorbers, stabilizers, cross-linking agents, lubricants, conductivity control agents, and the like are used.
[0044]
Next, the process cartridge and the electrophotographic apparatus of the present invention will be described.
[0045]
FIG. 1 shows a schematic configuration of a first example of an image forming apparatus having the process cartridge of the present invention.
[0046]
In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around a shaft 2 at a predetermined peripheral speed in a direction indicated by an arrow. The photoreceptor 1 receives a uniform charge of a predetermined positive or negative potential on the peripheral surface thereof by the primary charging means 3 during the rotation process, and then applies exposure light 4 from exposure means (not shown) such as laser beam scanning exposure. receive. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.
[0047]
The formed electrostatic latent image is developed with toner by a developing unit 5, and the developed toner developed image is taken out from a paper feeding unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1. The transfer means 6 sequentially transfers the transfer material 7 to the supplied and supplied transfer material 7.
[0048]
The transfer material 7 having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing, thereby being printed out of the apparatus as a copy.
[0049]
The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the untransferred toner by a cleaning unit 9, and further subjected to a static elimination process by a pre-exposure light 10 from a pre-exposure unit (not shown). Used for imaging. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required.
[0050]
In the present invention, among the above-described components such as the electrophotographic photosensitive member 1, the primary charging unit 3, the developing unit 5, and the cleaning unit 9, a plurality of components are integrally connected as a process cartridge. May be configured to be detachable from an image forming apparatus main body such as a copying machine or a laser beam printer. For example, the process cartridge 11 can be integrally supported together with the primary charging means 2 to form a cartridge, and the process cartridge 11 can be attached to and detached from the apparatus main body using guide means such as the rail 12 of the apparatus main body.
[0051]
When the electrophotographic apparatus is a copying machine or a printer, the exposure light 4 reads reflected light or transmitted light from an original, or reads an image with a sensor and converts it into a signal. Light emitted by driving the LED array or the like.
[0052]
FIG. 2 shows a schematic configuration of a color copying machine which is a second example of the image forming apparatus of the present invention.
[0053]
In the figure, reference numeral 201 denotes an image scanner unit which reads a document and performs digital signal processing. Reference numeral 202 denotes a printer unit which prints out an image corresponding to the document image read by the image scanner 201 on a sheet in full color.
[0054]
In the image scanner unit 201, reference numeral 200 denotes an original plate, an original 204 on an original platen glass 203 is irradiated with light from a halogen lamp 205 passing through an infrared cut filter 208, and reflected light from the original 204 is reflected by a mirror 206. The light is guided to a lens 207, forms an image on three CCD line sensors (CCD) 210 by a lens 209, and is sent to a signal processing unit 211 as full-color information red (R), green (G), and blue (B) components. Note that 205 and 206 are speeds v and 207 is 1/2 v mechanically in a direction perpendicular to an electrical scanning direction (hereinafter, referred to as a main scanning direction) of the line sensor (hereinafter, referred to as a sub-scanning direction). By moving, the entire surface of the document is scanned.
[0055]
The signal processing unit 211 electrically processes the read signal, decomposes the signal into magenta (M), cyan (C), yellow (Y), and black (BK) components. One printout is completed by scanning the document four times.
[0056]
The M, C, Y, and BK image signals sent from the image scanner unit 201 are sent to the laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal. The laser beam scans on the photosensitive drum 217 via the polygon mirror 214, the f-θ lens 215, and the mirror 216.
[0057]
Reference numeral 218 denotes a rotary developing device, which includes a magenta developing device 219, a cyan developing device 220, a yellow developing device 221 and a black developing device 222. The four developing devices alternately contact the photosensitive drum, and The formed M, C, Y, and BK electrostatic latent images are developed with corresponding toner.
[0058]
Reference numeral 223 denotes a transfer drum which winds a sheet fed from the sheet cassette 224 or 225 around the transfer drum 223 and transfers a toner image developed on the photosensitive drum 217 to the sheet.
[0059]
After the four colors of M, C, Y, and BK are sequentially transferred in this manner, the sheet passes through the fixing unit 226, is fixed, and is discharged.
[0060]
【Example】
Hereinafter, the present invention will be described with reference to examples. The organosilicon-modified hole transporting compound represented by the formula (1) was synthesized, for example, as follows.
[0061]
[Synthesis Example 1]
Synthesis of 4,4'-bis [2- (methyldimethoxysilyl) ethyl] -4 "-methyl-triphenylamine
<Synthesis of 4-methyl-triphenylamine>
33.9 g (166 mmol) of iodobenzene, 22.9 g (166 mmol) of anhydrous potassium carbonate and 7.0 g of copper powder were added to 20 ml of 4-nitrotoluene, and heated under reflux with stirring for 8 hours. After cooling, the mixture was filtered to remove the filtrate. The obtained reaction mixture was passed through a silica gel column to obtain 4-methyl-triphenylamine. Yield 13.5g.
[0062]
<Synthesis of 4,4′-diformyl-4 ″ -methyl-triphenylamine>
53.6 g of 4-methyl-triphenylamine and 35.5 ml of DMF were placed in a three-necked flask, and 84.4 ml of phosphorus oxychloride was added dropwise with stirring under ice-water cooling. After completion of the dropwise addition, the mixed solution was reacted at 95 ° C. for 5 hours, poured into 4 L of warm water and stirred for 1 hour. Thereafter, the precipitate was filtered off and washed with a mixed solution of ethanol / water (1: 1) to obtain 4,4′-diformyl-4 ″ -methyl-triphenylamine. Yield 51.5 g.
[0063]
<Synthesis of 4,4′-divinyl-4 ″ -methyl-triphenylamine>
12.1 g of sodium hydride and 580 ml of 1,2-dimethoxyethane were placed in a three-necked flask, and 108.5 g of trimethylphosphonium bromide was added while stirring at room temperature. Next, one drop of absolute ethanol was added, and the mixture was reacted at 70 ° C. for 4 hours. 47.9 g of 4,4′-diformyl-4 ″ -methyl-triphenylamine was added to the reaction mixture obtained as described above, and the mixture was reacted at 70 ° C. for 5 hours. The obtained cake was extracted with ether, combined with the filtrate, and washed with water. Then, the ether solution was dehydrated with calcium chloride, and the ether was removed to obtain a reaction mixture. This was recrystallized twice with ethanol to obtain acicular 4,4'-divinyl-4 ''-methyl-triphenylamine. Yield 40.2g.
[0064]
<Hydrosilylation of 4,4′-divinyl-4 ″ -methyl-triphenylamine>
40 ml of toluene, 3.84 g of methyldimethoxysilane and 0.54 mmol of a toluene solution of tris (tetramethyldivinyldisiloxane) diplatinum (0) are placed in a three-necked flask, and stirred at room temperature with 4,4′-divinyl-4. 20 ml of a toluene solution of 4.71 g of '' -methyl-triphenylamine was added dropwise. After completion of the dropwise addition, the mixture was stirred at 70 ° C. for 3 hours, and then the solvent was removed under reduced pressure. Triphenylamine was obtained. Yield 6.76 g.
[0065]
When 8.0 g of the synthesized 4,4′-bis [2- (methyldimethoxysilyl) ethyl] -4 ″ -methyl-triphenylamine was dissolved in 12.0 g of isopropanol, a uniform and transparent solution was obtained.
[0066]
This solution was applied on a copper substrate by a wire bar coating method, and thermally cured at 120 ° C. for 12 hours to form a film of about 5 μm. Next, a translucent gold electrode was formed by vapor deposition.
[0067]
The drift mobility of this sample was measured by a time-of-flight method using a nitrogen laser having a pulse width of 3 nsec and a wavelength of 337 nm. ^-7 cm ² / Vsec.
[0068]
[Synthesis Example 2]
Synthesis of 4,4′-bis [2- (triethoxysilyl) ethyl] -3 ″, 4 ″ -dimethyl-triphenylamine
<Synthesis of 3,4-dimethyl-triphenylamine>
33.9 g (166 mmol) of iodobenzene, 22.9 g (166 mmol) of anhydrous potassium carbonate and 7.0 g of copper powder were added to 25 ml of 4-nitro-o-xylene, and heated to reflux for 8 hours with stirring. After cooling, the mixture was filtered to remove the filtrate. The obtained reaction mixture was passed through a silica gel column to obtain 3,4-dimethyl-triphenylamine. Yield 14.2 g.
[0069]
<Synthesis of 4,4′-diformyl-3 ″, 4 ″ -dimethyl-triphenylamine>
56.5 g of 3,4-dimethyl-triphenylamine and 35.5 ml of DMF were placed in a three-necked flask, and 84.4 ml of phosphorus oxychloride was added dropwise with stirring under ice-water cooling. After completion of the dropwise addition, the mixed solution was reacted at 95 ° C. for 5 hours, poured into 4 L of warm water and stirred for 1 hour. Thereafter, the precipitate was filtered off and washed with a mixed solution of ethanol / water (1: 1) to obtain 4,4′-diformyl-3 ″, 4 ″ -dimethyl-triphenylamine. Yield 53.8 g.
[0070]
<Synthesis of 4,4′-divinyl-3 ″, 4 ″ -dimethyl-triphenylamine>
12.1 g of sodium hydride and 580 ml of 1,2-dimethoxyethane were placed in a three-necked flask, and 108.5 g of trimethylphosphonium bromide was added while stirring at room temperature. Next, one drop of absolute ethanol was added, and the mixture was reacted at 70 ° C. for 4 hours. 50.1 g of 4,4′-diformyl-3 ″, 4 ″ -dimethyl-triphenylamine was added to the reaction mixture obtained as above, and the mixture was reacted at 70 ° C. for 5 hours. Then, the obtained cake was extracted with ether, combined with the filtrate, and washed with water. Then, the ether solution was dehydrated with calcium chloride, and the ether was removed to obtain a reaction mixture. This was recrystallized twice with ethanol to obtain acicular, 4,4′-divinyl-3 ″, 4 ″ -dimethyl-triphenylamine. Yield 42.0 g.
[0071]
<Hydrosilylation of 4,4′-divinyl-3 ″, 4 ″ -dimethyl-triphenylamine>
40 ml of toluene, 6.0 g of triethoxysilane and 0.54 mmol of a toluene solution of tris (tetramethyldivinyldisiloxane) diplatinum (0) are placed in a three-necked flask, and stirred at room temperature with 4,4′-divinyl-3. 20 ml of a toluene solution of 4.92 g of '', 4 ''-dimethyl-triphenylamine was added dropwise. After completion of the dropwise addition, the mixture was stirred at 70 ° C. for 3 hours, and then the solvent was removed under reduced pressure to give pale yellow oily 4,4′-bis [2- (triethoxysilyl) ethyl] -3 ″, 4 ′. '-Dimethyl-triphenylamine was obtained. Yield 7.50 g.
[0072]
When 8.0 g of the synthesized 4,4′-bis [2- (triethoxysilyl) ethyl] -3 ″, 4 ″ -dimethyl-triphenylamine was dissolved in 12.0 g of isopropanol, a uniform and transparent solution was obtained. It became.
[0073]
Hereinafter, the present invention will be described in more detail with reference to examples. In addition, "part" in an Example shows a weight part.
[0074]
[Example 1]
Conductive barium sulfate was obtained by dissolving 167 parts of a phenol resin (trade name: Plyofen, manufactured by Dainippon Ink and Chemicals, Inc.) in 100 parts of methyl cellosolve on an aluminum cylinder having an outer diameter of 30 mm obtained by drawing. A dispersion in which 200 parts of ultrafine particles (primary particle diameter: 50 nm) and 3 parts of silicone resin particles having an average particle diameter of 2 μm were dispersed was applied by a dip coating method, and a dried conductive layer having a thickness of 15 μm was formed.
[0075]
A solution obtained by dissolving 5 parts of alcohol-soluble copolymerized nylon (trade name: Amilan CM-8000, manufactured by Toray Industries, Inc.) in 95 parts of methanol was applied onto the conductive layer by a coating method. After drying at 80 ° C. for 10 minutes, an undercoat layer having a thickness of 0.5 μm was formed.
[0076]
Next, strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.9 ° of the Bragg angles (2θ ± 0.2 °) in CuKα characteristic X-ray diffraction were obtained as the dispersion for the charge generation layer. 5 parts of the oxytitanyl phthalocyanine pigment was added to a solution prepared by dissolving 2 parts of polyvinyl benzal (a degree of benzalization of 75% or more) in 95 parts of cyclohexanone, and dispersed by a sand mill for 2 hours.
[0077]
The dispersion was dipped on the undercoat layer formed previously so that the film thickness after drying was 0.2 μm, and applied by a coating method.
[0078]
Next, 9 parts of a triarylamine compound having the following structural formula and 10 parts of a polycarbonate resin (trade name: Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) were dissolved in 70 parts of chlorobenzene. This solution was applied onto the charge generation layer by dipping and applied by a coating method. After drying, a 12 μm charge transport layer was provided.
[0079]
Embedded image

Next, 30 parts of isopropyl alcohol, 18 parts of water, and 1 part of acetic acid were added to 45 parts of methyltriethoxysilane while stirring. After the addition, the mixed solution was heated to 60 ° C. and reacted for 2 hours. Thereafter, the reaction solution was diluted with 30 parts of isopropyl alcohol and stirred for 48 hours. To this solution, 17 parts of 4,4′-bis [2- (methyldimethoxysilyl) ethyl] -4 ″ -methyl-triphenylamine synthesized in Synthesis Example 1, 57 parts of isopropanol, and 1 part of dibutyltin dilaurate are added. did.
[0080]
This preparation was applied onto the charge transport layer by dip coating, and dried to obtain a 3 μm surface layer.
[0081]
This electrophotographic photoreceptor was charged to -600 V, and electrophotographic characteristics were measured using light having a wavelength of 680 nm. _1/2 (Exposure amount required to reduce the charging potential to −300 V) is 0.23 J / cm ² And the residual potential was as good as -60V.
[0082]
This electrophotographic photoreceptor was modified using a modified laser beam printer LBP-SX from Canon ((1 / e2) modified to have an irradiation spot diameter of 63.5 μm in the sub-scanning direction and 20 μm in the main scanning direction). When the image was evaluated at an initial charge of -600 V, the image was not deteriorated even after the durability test of 5000 sheets, and the reproducibility of one pixel of the highlight portion in an input signal equivalent to 600 dpi was sufficient.
[0083]
[Comparative Example 1]
In the same manner as in Example 1, up to the charge transport layer was formed. Next, the 4,4′-bis [2- (methyldimethoxysilyl) ethyl] -4 ″ -methyl-triphenylamine synthesized in Synthesis Example 1 was subjected to the method described in Synthesis Example 5 of JP-A-9-19004. A coating solution for a surface layer was prepared in the same manner as in Example 1 except that 4- [2- (triethoxysilyl) ethyl] -triphenylamine was used, but the solution was cloudy. .
[0084]
This preparation was applied onto the charge transport layer by the dip coating method and dried. As a result, a large number of spots were generated and a film having good surface properties could not be obtained.
[0085]
[Example 2]
On the same aluminum cylinder as in Example 1, 167 parts of a phenol resin (trade name: Plyofen, manufactured by Dainippon Ink and Chemicals, Inc.) was dissolved in 100 parts of methyl cellosolve, and the conductive barium sulfate ultrafine particles (1 A dispersion in which 200 parts of a secondary particle diameter (50 nm) was dispersed was applied by a dip coating method so that the film thickness after drying was 10 μm. In the same manner as in Example 2, an undercoat layer having a thickness of 1 μm, a charge generation layer having a thickness of 0.2 μm, and a charge transport layer having a thickness of 12 μm were formed on this conductive support.
[0086]
Next, 30 parts of isopropyl alcohol, 18 parts of water, and 1 part of acetic acid were added to 45 parts of methyltriethoxysilane while stirring. After the addition, the mixed solution was heated to 60 ° C. and reacted for 2 hours. Thereafter, the reaction solution was diluted with 30 parts of isopropyl alcohol and stirred for 48 hours. To this solution, 17 parts of 4,4′-bis [2- (triethoxysilyl) ethyl] -3 ″, 4 ″ -dimethyl-triphenylamine synthesized in Synthesis Example 2, 57 parts of isopropanol, and dibutyltin dilaurate One part was added.
[0087]
This preparation was applied onto the charge transport layer by dip coating, and dried to obtain a 3 μm surface layer.
[0088]
This electrophotographic photoreceptor was charged to -600 V, and electrophotographic characteristics were measured using light having a wavelength of 680 nm. _1/2 (Exposure amount required to reduce the charging potential to -300 V) is 0.22 J / cm ² And the residual potential was -57V, which was very good.
[0089]
This electrophotographic photoreceptor was evaluated at an initial charge of -500 V using a Canon laser beam printer similar to that in Example 2, and the image was evaluated. Even after a durability test of 5,000 sheets, the image was not deteriorated, and was equivalent to 600 dpi. The one-pixel reproducibility of the highlight portion in the input signal of (1) was also sufficient.
[0090]
[Comparative Example 2]
In the same manner as in Example 1, up to the charge generation layer was formed. Next, 6 parts of the following triarylamine compound:
[0091]
Embedded image

A solution for a charge transport layer in which 6 parts of a polycarbonate resin (trade name: Z200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is dissolved in 70 parts of chlorobenzene is applied on the charge generation layer of Example 2 by a dip coating method. As a result, a charge transport layer having a thickness of 20 μm after drying was formed. This electrophotographic photoreceptor was charged to -600 V, and electrophotographic characteristics were measured using light having a wavelength of 680 nm. _1/2 (Exposure amount required to reduce the charging potential to -300 V) is 0.38 J / cm ² And the residual potential was as large as -120V.
[0092]
This electrophotographic photoreceptor was modified using a modified laser beam printer LBP-SX from Canon ((1 / e2) modified to have an irradiation spot diameter of 63.5 μm in the sub-scanning direction and 40 μm in the main scanning direction). Image evaluation was performed with the initial charge set to -600 V. After a durability test on 4000 sheets, interference fringes and black spots were recognized, and the reproducibility of one pixel of a highlight portion in an input signal equivalent to 600 dpi was insufficient. There was unevenness.
[0093]
[Example 3]
On an aluminum cylinder having an outer diameter of 80 mm, 50 parts of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide, 25 parts of phenol resin, 30 parts of methyl cellosolve, 30 parts of methanol and silicone oil (polymethylsiloxane) (Polyoxyalkylene copolymer, weight average molecular weight 3000) 0.002 parts of the conductive layer paint prepared by dispersing and adjusting for 2 hours with a sand mill containing 1 mm glass beads was dried and dried at 140 ° C. for 30 minutes to form a film. A 20 μm conductive layer was formed.
[0094]
Next, a solution prepared by dissolving 5 parts of alcohol-soluble copolymerized nylon (trade name: Amilan CM-8000, manufactured by Toray Industries, Inc.) in 95 parts of methanol was applied by a dip coating method. After drying at 80 ° C. for 10 minutes, an undercoat layer having a thickness of 1 μm was formed.
[0095]
Next, as a charge generation layer, 5 parts of the following bisazo pigment was added to a solution prepared by dissolving 2 parts of polyvinyl benzal (degree of benzalization of 75% or more) in 95 parts of cyclohexanone, and dispersed by a sand mill for 20 hours. The dispersion was dipped on the undercoat layer formed previously so that the film thickness after drying was 0.2 μm, and applied by a coating method.
[0096]
Embedded image

Next, 7 parts of a triarylamine compound having the following structural formula and 10 parts of a polycarbonate resin (trade name: Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) were dissolved in 70 parts of chlorobenzene. This solution was applied onto the charge generation layer by dipping and applied by a coating method. After drying, a 12 μm charge transport layer was provided.
[0097]
Embedded image

Next, 30 parts of isopropyl alcohol, 18 parts of water were added to 40 parts of methyltriethoxysilane and 9 parts of 3,3,4,4,5,5,6,6,6-nonafluorohexyltriethoxysilane while stirring. One part of acetic acid was added. After the addition, the mixed solution was heated to 60 ° C. and reacted for 2 hours. Thereafter, the reaction solution was diluted with 30 parts of isopropyl alcohol and stirred for 48 hours. To this solution, 22 parts of 4,4′-bis [2- (methyldimethoxysilyl) ethyl] -4 ″ -methyl-triphenylamine synthesized in Synthesis Example 1, 74 parts of isopropanol, and 1 part of dibutyltin dilaurate are added. did.
[0098]
This preparation was applied onto the charge transport layer by dip coating, and dried to obtain a 3 μm surface layer.
[0099]
This electrophotographic photoreceptor was charged to -700 V, and electrophotographic characteristics were measured using light having a wavelength of 680 nm. _1/2 (Exposure amount required to reduce the charging potential to -350 V) is 0.81 μJ / cm ² And the residual potential was as good as -32V.
[0100]
Using this electrophotographic photoreceptor, an initial charge of -700 V was applied to an evaluation machine modified by using a Canon full-color copier CLC-500 having an irradiation spot diameter of 63.5 μm in the sub-scanning direction and 20 μm in the main scanning direction. When the image was evaluated at the initial setting and after the 100,000-sheet durability test, there was no charge injection such as black spots and no interference fringes, an image output with excellent uniformity was obtained, and the tone reproducibility was 400 dpi. 256 gradations were extremely good.
[0101]
【The invention's effect】
An electrophotographic photoreceptor having both mechanical and electrical durability that has surface durability, does not cause light scattering or bleeding, and does not cause deterioration of electrical characteristics such as decrease in sensitivity and increase in residual potential, and the electrophotography. A process cartridge having a photoconductor and an image forming apparatus can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a schematic configuration of a first example of an image forming apparatus of the present invention.
FIG. 2 is a diagram illustrating a schematic configuration of a second example of the image forming apparatus of the present invention.
[Explanation of symbols]
1. Electrophotographic photoreceptor of the present invention
2 axes
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 rails
200 original plate
201 Image Scanner Unit
202 Printer section
203 Platen glass
204 manuscript
205 Halogen lamp
206, 207 mirror
208 infrared cut filter
209 lens
210 3-line sensor
211 signal processing unit
212 Laser Driver
213 Semiconductor laser
214 polygon mirror
215 f-θ lens
216 mirror
217 Photoconductor drum
218 Rotary developing machine
219 Magenta developing machine
220 cyan developing machine
221 Yellow developing machine
222 black developing machine
223 Transfer drum
224,225 paper cassette
226 Fixing unit

Claims (9)

In an electrophotographic photosensitive member having a photosensitive layer on a support, the surface layer of the electrophotographic photosensitive member has the following formula (1)

(Wherein, A represents a hole transporting group having a number of aromatic rings, R ¹ represents a substituted or unsubstituted organic group, Q represents a hydrolyzable group or a hydroxyl group, and R ² represents a substituted or unsubstituted group. Represents an unsubstituted monovalent hydrocarbon group, n represents an integer of 1 to 3, m represents a positive integer, and m / a ≧ 0.5.)
An electrophotographic photoreceptor comprising a polycondensation product of an organosilicon-modified hole-transporting compound represented by the formula and an alcohol-soluble siloxane resin. After forming the charge generating layer and the charge transporting layer on the support, a surface protective layer was formed by immersing in a solution containing the organic silicon-modified hole transporting compound, the alcohol-soluble siloxane resin and the alcohol. The electrophotographic photosensitive member according to claim 1, wherein: The siloxane resin has the following general formula (2)

(In the formula (2), ^{R 3} represents an alkyl group having 1 to 3 carbon atoms, a vinyl group, a phenyl _{group, C x F 2x + 1 C} 2 H 4 - is (x 1 to 18 integer), .gamma. glycidol A xypropyl group or a γ-methacryloxypropyl group.)
The electrophotographic photosensitive member according to claim 1, further comprising a polycondensation product of a siloxane resin represented by the formula: In the above formula (1), A is the following formula (3)

(R ⁴ , R ⁵ and R ⁶ are organic groups, at least one of which contains an aromatic hydrocarbon ring group or an aromatic heterocyclic group, and R ⁴ , R ⁵ and R ⁶ are the same or different. May be.)
The electrophotographic photoreceptor according to claim 1, wherein The electrophotographic photoreceptor according to any one of claims 1 to 4, wherein the polycondensation product of the modified organosilicon hole transporting compound represented by the formula (1) has an ionization potential of 4.5 to 6.2 eV. The electrophotographic photosensitive member according to any one of claims 1 to 5, wherein A in the formula (1) has a triphenylamine structure. The electrophotographic photosensitive member according to claim 1, wherein m = 2 to 3 and a = 3 to 6 in the above formula (1). A charging unit for charging the electrophotographic photosensitive member according to any one of claims 1 to 7, a developing unit for developing the electrophotographic photosensitive member on which an electrostatic latent image is formed with toner, and It is integrally supported together with at least one means selected from the group consisting of cleaning means for recovering toner remaining on the electrophotographic photosensitive member after the transfer step, and is detachably mounted on the main body of the electrophotographic apparatus. Process cartridge. 8. An electrophotographic photosensitive member according to claim 1, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, An image forming apparatus, comprising: developing means for developing the electrophotographic photosensitive member on which an electrostatic latent image is formed with toner; and transfer means for transferring a toner image on a transfer material.

Images