JP3595636B2 - Electrophotographic photoreceptor manufacturing method, electrophotographic photoreceptor, process cartridge having electrophotographic photoreceptor, and electrophotographic apparatus - Google Patents

Description

（Ｘ₁は、炭素原子または単結合（この際のＲ₅ 及びＲ₆はなし）を示し、Ｒ₁〜Ｒ₄は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基を示し、Ｒ₅、Ｒ₆は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基、あるいはＲ₅とＲ₆が結合することによって形成されるアルキリデン基を示し、Ｒ₇〜Ｒ₁₀は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基を示す。）
【００１７】
【化８】

（Ｘ₂は、炭素原子または単結合（この際のＲ₁₅ 及びＲ₁₆はなし）を示し、Ｒ₁₁〜Ｒ₁₄は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基を示し、Ｒ₁₅、Ｒ₁₆は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基、あるいはＲ₁₅とＲ₁₆が結合することによって形成されるアルキリデン基を示す。）
【００１８】
また、本発明は、上記製造方法により製造された電子写真感光体である。
【００１９】
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電子写真装置である。
【００２０】
【発明の実施の形態】
式（１）及び（２）中、ハロゲン原子としてはフッ素原子、塩素原子、臭素原子等が挙げられ、アルキル基としてはメチル基、エチル基、プロピル基、ブチル基等が挙げられ、アリール基としてはフェニル基、ナフチル基等が挙げられ、シクロアルキリデン基としてはシクロヘキシリデン基等が挙げられる。上記アルキル基、アリール基、シクロアルキリデン基が有してもよい置換基としては、メチル基、エチル基、プロピル基、ブチル基等のアルキル基、フェニル基、ナフチル基等のアリール基、フッ素原子、塩素原子、臭素原子等のハロゲン原子等が挙げられる。
【００２１】
式（１）で示される構成単位の具体例を表１〜５に示すが、本発明はこれらに限られるものではない。
【００２２】
【表１】

【００２３】
【表２】

【００２４】
【表３】

【００２５】
【表４】

【００２６】
【表５】

【００２７】
本発明において用いられる、式（１）で示される構成単位を有する重合体は、通常、溶解性や剛直性の制御のため、テレフタル酸塩化物、イソフタル酸塩化物の混合物にて用いられ、アルカリ下で溶媒／水系中で各種ビスフェノールと攪拌することにより界面重合を行うことができる。すなわち表１〜５に示した式は、テレフタル酸塩化物、イソフタル酸塩化物の混合系から調製された形として表わした。しかし、テレフタル酸塩化物、イソフタル酸塩化物の比率はその重合体の溶解性を考慮して決定されるもので、定説はない。ただし、いずれかの塩化物が３０ｍｏｌ％以下になると、合成した重合体の溶解性が極端に低下するので注意が必要である。通常は１／１の比率で合成するのが好ましい。本発明の電子写真感光体においては、式（１）で示される構成単位が同一のもので構成される重合体でも、２種類以上の式（１）で示される別種の構成単位からなる共重合体でもよい。
【００２８】
式（２）で示される構成単位の具体例を表６〜９に示すが、本発明はこれらに限られるものではない。
【００２９】
【表６】

【００３０】
【表７】

【００３１】
【表８】

【００３２】
【表９】

【００３３】
また、式（１）で示される構成単位を有するポリアリレート及び式（２）で示される構成単位を有するポリカーボネートを可溶媒中に溶解混合し、貧溶媒により再沈殿して得られたブレンド材料を含有することにより、本発明の効果を発現することが可能である。溶解−再沈殿は常法で行うことができる。たとえば、ジクロロメタン、クロロホルム等の可溶解の溶媒に、ポリアリレート及びポリカーボネートを十分に溶解させる。次に、この混合ポリマー溶液をメタノールや水等の貧溶媒から再沈殿させて、綿状のポリマーが得られる。これを真空乾燥させてブレンド材料が得られる。この材料は、各々を単純ブレンドしたポリアリレート／ポリカーボネートより溶解性、塗料安定性が向上している。この方法は、いずれのポリアリレート／ポリカーボネートでも有効であるが、特に溶解性の劣るビスフェノールＡ型ポリカーボネート（具体例２−１）やビスフェノールＺ型ポリアリレート（具体例１−２２）では特性改良に効果的である。
【００３４】
詳細なメカニズムは十分には解明できてはいないが、各ポリマーをあらかじめ溶液中にてブレンドすることにより、ポリカーボネート構造とポリアリレート構造が高度にブレンドでき、得られたブレンド材料は、各々の分子鎖間に入り込んでいるため新たな特性を発現しやすくなったと推定される。
【００３５】
また、異なる構造の分子がブレンドされることにより、各々の結晶性を崩していると考えられることから、各溶媒への溶解性を向上していると考えられ、さらに保存時のゲル化等も抑制することが可能となったと推定される。
【００３６】
また、電子写真特性の低下が少なくなる要因としては、次のように推測される。ポリアリレートが機械的強度に優れている要因の１つであるフタル酸エステル構造は、電荷輸送材料との組み合わせによりキャリアーのトラップ要因の１つになると予想されているが、ポリカーボネートが分子レベルでポリアリレートの近傍に存在することにより回避されていると推測される。さらに、ポリマー中の残留不純物（残モノマー、塩化物等）は、諸特性の悪化要因の１つであるが、本発明のブレンド系では溶解性の向上により精製の容易性が上がり、電子写真特性の悪化を抑制していると考えられる。
【００３７】
なお、本発明においては、ポリアリレート及びポリカーボネートの粘度平均分子量は１０，０００〜２００，０００であることが好ましく、特には１５，０００〜１００，０００であることが好ましい。また、ポリアリレートの分子量とポリカーボネートの分子量は同程度のものであることが好ましく、その差は５，０００以内であることが好ましい。
【００３８】
さらに、下記式（３）で示される構成単位及び下記式（４）で示される構成単位を有する共重合体を含有することにより、表面の潤滑性、耐ソルベントクラック性等がより向上する。
【００３９】
【化９】

（Ｒ₁₇〜Ｒ₂₂は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基を示し、ｎは、正の整数を示す。）
【００４０】
【化１０】

（Ｘ₃は、炭素原子または単結合（この際のＲ₂₇ 及びＲ₂₈はなし）を示し、Ｒ₂₃〜Ｒ₂₆は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基を示し、Ｒ₂₇、Ｒ₂₈は、水素原子、ハロゲン原子、置換されてもよいアルキル基または置換されてもよいアリール基、あるいはＲ₂₇とＲ₂₈が結合することによって形成されるアルキリデン基を示す。）
【００４１】
式（３）及び（４）中、ハロゲン原子としてはフッ素原子、塩素原子、臭素原子等が挙げられ、アルキル基としてはメチル基、エチル基、プロピル基、ブチル基等が挙げられ、アリール基としてはフェニル基、ナフチル基等が挙げられ、シクロアルキリデン基としてはシクロヘキシリデン基等が挙げられる。上記アルキル基、アリール基、シクロアルキリデン基が有してもよい置換基としては、メチル基、エチル基、プロピル基、ブチル基等のアルキル基、フェニル基、ナフチル基等のアリール基、フッ素原子、塩素原子、臭素原子等のハロゲン原子等が挙げられる。ｎは、正の整数を示し、１〜２００であることが好ましい。
【００４２】
式（３）で示される構成単位の具体例を表１０〜１２に示すが、これらに限られるものではない。
【００４３】
【表１０】

【００４４】
【表１１】

【００４５】
【表１２】

【００４６】
式（４）については、表６〜９に示された式（２）と同一であるので、式（４）の具体例は、表６〜９の例を適用する。
【００４７】
この分子レベルにおけるブレンドが分子内密度を上げ、且つ非晶質部分と結晶質部分を同一分子内に併せ持つため塗膜形成時に発生する分子内応力をも緩和することができ、それによりソルベントクラックの要因となる薬品が侵入しても内部応力を維持しクラックが生じないと推定される。さらに、式（３）で示される構成単位及び式（４）で示される構成単位を有する共重合体であるポリカーボネートを含有させることにより、クラックを生じさせるソルベントの浸透を防ぐことと、ポリマー内部での応力緩和により、効果的に耐ソルベントクラック性を向上できる。
【００４８】
以下、本発明の電子写真感光体の構成について説明する。
【００４９】
本発明の電子写真感光体は、感光層が電荷輸送材料と電荷発生材料とを同一の層に含有する単層型であっても、あるいは電荷輸送材料を含有する電荷輸送層と電荷発生材料を含有する電荷発生層とが分離した積層型でもよいが、電子写真特性からは積層型が好ましい。いずれの場合も、少なくとも電子写真感光体の表面層が、式（１）で示される構成単位を有するポリアリレートと、式（２）で示される構成単位を有するポリカーボネートとを含有する。
【００５０】
使用する導電性支持体は、導電性を有するものであればよく、アルミニウム、ステンレス等の金属、あるいは導電層を設けた金属、紙、プラスチック等が挙げられ、形状はシート状、円筒状等が挙げられる。特に、ＬＢＰ等の画像入力がレーザー光の場合は、散乱による干渉縞防止、または支持体の傷を被覆することを目的とした導電層を設けることが好ましい。これはカーボンブラック、金属粒子等の導電性粉体をバインダー樹脂に分散させて形成することができる。導電層の膜厚は５〜４０μｍ、好ましくは１０〜３０μｍが適当である。
【００５１】
その上に必要に応じて接着機能及びバリアー機能を有する中間層を設けることができる。中間層の材料としては、ポリアミド、ポリビニルアルコール、ポリエチレンオキシド、エチルセルロース、カゼイン、ポリウレタン、ポリエーテルウレタン等が挙げられる。これらは適当な溶剤に溶解して塗布される。中間層の膜厚は０．０５〜５μｍ、好ましくは０．３〜１μｍが適当である。
【００５２】
機能分離型の場合、その上には電荷発生層が形成される。本発明に用いられる電荷発生材料としては、セレン−テルル、ピリリウム、チアピリリウム系染料、フタロシアニン、アントアントロン、ジベンズピレンキノン、トリスアゾ、シアニン、ジスアゾ、モノアゾ、インジゴ、キナクリドン、非対称キノシアニン系の各顔料が挙げられる。電荷発生層は前記電荷発生材料を０．３〜４倍量のバインダー樹脂及び溶剤とともにホモジナイザー、超音波分散、ボールミル、振動ボールミル、サンドミル、アトライター、ロールミル及び液衝突型高速分散機等を使用してよく分散し、分散液を塗布、乾燥させて形成される。電荷発生層の膜厚は５μｍ以下、好ましくは０．１〜２μｍが適当である。
【００５３】
電荷輸送層は、主として電荷輸送材料とバインダー樹脂とを溶剤中に溶解させた塗料を塗布、乾燥して形成する。用いられる電荷輸送材料としては、トリアリールアミン系化合物、ヒドラゾン化合物、スチルベン化合物、ピラゾリン系化合物、オキサゾール系化合物、トリアリルメタン系化合物、チアゾール系化合物等が挙げられる。
【００５４】
これらは０．５〜２倍量のバインダー樹脂と組み合わされ、塗布、乾燥して電荷輸送層を形成する。電荷輸送層の膜厚は５〜４０μｍ、好ましくは１５〜３０μｍが適当である。
【００５５】
感光層が単層型の場合は、上述のような電荷発生材料や電荷輸送材料を上述のようなバインダー樹脂に分散、溶解した溶液を塗布、乾燥することによって形成される。膜厚は５〜４０μｍ、好ましくは１５〜３０μｍが適当である。
【００５６】
図１に本発明の電子写真感光体を有するプロセスカートリッジを有する電子写真装置の概略構成を示す。
【００５７】
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、スリット露光やレーザービーム走査露光等の像露光手段（不図示）からの画像露光光４を受ける。こうして感光体１の周面に静電潜像が順次形成されていく。
【００５８】
形成された静電潜像は、次いで現像手段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。
【００５９】
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）として装置外へプリントアウトされる。
【００６０】
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。
【００６１】
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電子写真装置本体に対して着脱可能に構成しても良い。例えば、一次帯電手段３、現像手段５及びクリーニング手段９の少なくとも１つを感光体１と共に一体に支持してカートリッジ化して、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。
【００６２】
また、画像露光光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、センサーで原稿を読取り、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アレイの駆動及び液晶シャッターアレイの駆動等により照射される光である。
【００６３】
本発明の電子写真感光体は電子写真複写機に利用するのみならず、レーザービームプリンター、ＣＲＴプリンター、ＬＥＤプリンター、液晶プリンター、レーザー製版等電子写真応用分野にも広く用いることができる。
【００６４】
以下、実施例に従って説明する。
【００６５】
【実施例】
まず、本発明で用いるポリアリレート及びポリカーボネートの合成法を示すが、これに限られたことではない。
【００６６】
式（１）で示される構成単位を有するポリアリレートは、所定のビスフェノール０．０１ｍｏｌを水酸化ナトリウム０．８ｇ、塩化テトラメチルアンモニウム１ｇを水１００ｍｌに溶かし、１リットルのミキサー中に投入し、これに１，２−ジクロロエタン３０ｍｌにテレフタル酸塩化物０．００５ｍｏｌ、イソフタル酸塩化物０．００５ｍｏｌを溶かしたものを攪拌しながら投入して１０分高速攪拌し、２時間放置後、１，２−ジクロロエタン液を回収し、これに大量のヘキサンを投入し、ポリマーとして回収したものである。
【００６７】
また、式（２）で示される構成単位を有するポリカーボネートは、所定のビスフェノールとホスゲンから常法により合成した。
【００６８】
さらに、本発明では、ポリアリレートとポリカーボネートのブレンドの方法は、溶媒中で溶解し貧溶媒で再沈殿させてブレンドする方法である。手順としては、まずポリアリレート／ポリカーボネート＝１／１（ｗｔ）を１０倍量（ｗｔ）のジクロロメタンに十分に溶解した。ついで溶解溶媒の１０倍量（ｗｔ）のメタノールを攪拌しながら、このポリマー溶液を徐々に滴下した。このメタノール中で白色綿状のブレンドポリマーを得た。これを真空乾燥しフレーク状にして用いた。
【００６９】
〔実施例１〕
３０φ２５４ｍｍのＡｌシリンダーを支持体とし、これに、以下の材料より構成される塗料を支持体上に浸漬法で塗布し、１４０℃、３０分熱硬化して膜厚１５μｍの導電層を形成した。
【００７０】
導電性顔料：ＳｎＯ₂コート処理硫酸バリウム １０部
抵抗調節用顔料：酸化チタン ２部
バインダー樹脂：フェノール樹脂 ６部
レベリング材：シリコーンオイル ０．００１部
溶剤：メタノール、メトキシプロパノール０．２／０．８ ２０部
【００７１】
次に、この導電層上に、Ｎ−メトキシメチル化ナイロン３部及び共重合ナイロン３部をメタノール６５部、ｎ−ブタノール３０部の混合溶媒に溶解した溶液を浸漬法で塗布し、膜厚０．５μｍの中間層を形成した。
【００７２】
次に、ＣｕＫαのＸ線回折における回折角２θ±０．２°が９．０°、１４．２°、２３．９°、２７．１°に強いピークを有するＴｉＯＰｃ４部とポリビニルブチラール（商品名：エスレックＢＭ２、積水化学製）２部及びシクロヘキサノン６０部をφ１ｍｍガラスビーズを用いたサンドミル装置で４時間分散したあと、エチルアセテート１００部を加えて電荷発生層用分散液を調製した。これを浸漬法で塗布し、膜厚０．３μｍの電荷発生層を形成した。
【００７３】
次に、電荷輸送層を形成するために、電荷輸送層用の塗料を調製した。ブレンドポリマーとして、ビスフェノールＡ型（具体例１−１）のポリアリレートとビスフェノールＡ型（具体例２−１）のポリカーボネートとを溶解／再沈殿によりブレンドすることによって調製したものを用いた。このブレンドポリマー１０部と、下記構造式のアミン化合物９部及び
【００７４】
【化１１】

下記構造式のアミン化合物１部を、
【００７５】
【化１２】

モノクロロベンゼン５０部及びジクロロメタン５０部の混合溶媒に溶解した。この塗料を浸漬法で塗布し、１２０℃、２時間乾燥して２５μｍの電荷輸送層を形成した。
【００７６】
次に評価について説明する。
【００７７】
装置は、ヒューレットパッカード製ＬＢＰ「レーザージェット４ｐｌｕｓ」（プロセススピード７１ｍｍ／ｓｅｃ）を改造して用いた。改造は、帯電器の直前にヒューズランプによる前露光を取り付けたことで、残留電位測定時のみ点灯させて使用した。電位測定は、暗部をＶｄ、レーザー光照射部をＶｌ、前露光照射部をＶｒとして行った。作成した電子写真感光体について、この装置で２３℃、５５％ＲＨ下で通紙耐久を行った。シーケンスは、プリント１枚ごとに１回停止する間欠モードとし、５０００枚を耐久した。さらにソルベントクラック性は、表面に指脂を付着させ２４時間放置し、顕微鏡観察によりソルベントクラックの有無を観察した。ポットライフの評価として、各電荷輸送層塗料を室温（２３℃）にて密閉容器中にて１週間静置した後、溶解状態を観察した。
【００７８】
〔実施例２〕
実施例１において、用いるブレンドポリマーとして、ビスフェノールＺ型（具体例１−２２）のポリアリレートとビスフェノールＺ型（具体例２−１３）のポリカーボネートとを溶解／再沈殿によりブレンドすることによって調製したものとした以外は同様に作製した。
【００７９】
〔比較例１〕
実施例１において、用いる電荷輸送層用のバインダー樹脂をビスフェノールＺ型（具体例１−２２）のポリアリレートのみとした以外は同様に作製しようとしたが、ポリマーが溶媒に十分には溶解せず、電荷輸送層用塗料の作製ができず、感光体が作製できなかった。
【００８０】
〔比較例２〕
実施例１において、用いる電荷輸送層用のバインダー樹脂をビスフェノールＡ型（具体例２−１）のポリカーボネートのみとした以外は同様に作製した。
【００８１】
〔参考例１〕
実施例１において、用いる電荷輸送層用のバインダー樹脂をビスフェノールＡ型（具体例１−１）のポリアリレートのみとした以外は同様に作製した。
【００８２】
〔参考例２〕
実施例１において、用いる電荷輸送層用のバインダー樹脂をビスフェノールＺ型（具体 例２−１３）のポリカーボネートのみとした以外は同様に作製した。
【００８３】
以上の実施例１及び２、比較例１及び２並びに参考例１及び２について、電荷輸送層用のバインダー樹脂の種類及び諸特性をまとめて下記の表１３に示す。
【００８４】
【表１３】

【００８５】
このように、特定のポリアリレートにポリカーボネートを含有させることにより、耐摩耗性をほぼ維持したまま、電子写真特性を改善できている。また、従来、溶解性やポットライフの面から使用できる構成単位に制限があったが、本発明は溶解性を改善できるため、感光体としての特性（機械的強度や、電子写真特性等）を優先して選択、使用することができる。
【００８６】
【発明の効果】
以上に説明したように本発明の電子写真感光体は、ポリアリレートの優れた機械的強度とポリカーボネートの良好な電子写真特性をもっている。また、溶解性、ポットライフの改善により、材料（構成単位）の選択の幅が広がり、利用目的に応じた電子写真感光体の提供が可能となった。
【図面の簡単な説明】
【図１】本発明の電子写真感光体を有するプロセスカートリッジを有する電子写真装置の概略構成の例を示す図である。
【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[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing an electrophotographic photoreceptor , an electrophotographic photoreceptor, a process cartridge having the electrophotographic photoreceptor, and an electrophotographic apparatus . More specifically, the present invention relates to an electrophotographic photoreceptor having a photosensitive layer containing a specific resin on a surface layer. the method of manufacturing electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.
[0002]
[Prior art]
The electrophotographic method comprises a photoconductor comprising a support coated with an insulating material in the dark where the electrical resistance varies according to the dose received during image exposure, as shown in U.S. Pat. No. 2,297,691. Use a conductive material. The basic characteristics required of an electrophotographic photoreceptor using this photoconductive material include (1) being able to be charged to an appropriate potential in a dark place, (2) having little potential dissipation in a dark place, (3) Quickly dissipating the charge by light irradiation, and the like.
[0003]
Conventionally, as an electrophotographic photosensitive member, an inorganic photosensitive member having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide, and cadmium sulfide as a main component has been widely used. However, they satisfy the above conditions (1) to (3), but are not always satisfactory in heat stability, moisture resistance, durability, and productivity. In recent years, electrophotographic photoreceptors containing various organic photoconductive compounds as main components have been actively developed in order to overcome the disadvantages of inorganic photoreceptors. For example, U.S. Pat. No. 3,838,851 discloses a photoreceptor having a charge transport layer containing triallylpyrazoline, and U.S. Pat. No. 3,871,880 discloses a condensation of a charge generating layer comprising a derivative of perylene pigment with 3-propylene and formaldehyde. Photoreceptors and the like comprising a charge transport layer comprising a body are known.
[0004]
Further, the organic photoconductive compound can freely select the photosensitive wavelength range of the electrophotographic photosensitive member depending on the compound. For example, in the case of azo pigments, JP-A-61-272754 and JP-A-56-167759. The substances disclosed in the publications exhibit high sensitivity in the visible region, and the compounds disclosed in JP-A-57-19576 and JP-A-61-228453 are sensitive to the infrared region. Are shown. Among these materials, those exhibiting sensitivity in the infrared region are used in laser beam printers (hereinafter abbreviated as LBPs) and LED printers, which have been making remarkable progress in recent years, and the demand frequency is increasing. Electrophotographic photoreceptors using these organic photoconductive compounds are used as function-separated type photoreceptors in which a charge transport layer and a charge generation layer are laminated in order to satisfy both electrical and mechanical properties. Often. On the other hand, as a matter of course, the electrophotographic photoreceptor is required to have sensitivity, electrical characteristics, and optical characteristics according to the applied electrophotographic process. In particular, in the case of an electrophotographic photoreceptor that is used repeatedly, the surface of the electrophotographic photoreceptor is directly subjected to an electrical or mechanical external force such as corona or direct charging, image exposure, toner development, transfer process, surface cleaning, etc. Also, durability for them is required.
[0005]
Specifically, electrical deterioration due to ozone and nitrogen oxide during charging, discharge during charging, mechanical deterioration in which the surface is worn or scratched due to rubbing of the cleaning member, and electrical deterioration Durability is required. The electrical deterioration is particularly problematic in that carriers stay in a portion irradiated with light and a potential difference is generated from a portion not irradiated with light, and this phenomenon occurs as a photo memory. The mechanical deterioration is particularly different from the inorganic photoreceptor, and the organic photoreceptor having many soft materials is inferior in the durability against the mechanical deterioration, and the improvement of the durability is particularly desired. Various attempts have been made to satisfy the durability characteristics required for the photoreceptor as described above.
[0006]
As a resin commonly used for the surface layer and having excellent abrasion and electrical properties, a polycarbonate resin having bisphenol A as a skeleton has attracted attention. However, not all of the above-mentioned problems can be solved. It has the following problems.
(1) Poor solubility, showing good solubility only in a part of halogenated aliphatic hydrocarbons such as dichloromethane and 1,2-dichloroethane, and since these solvents have a low boiling point, these solvents are used. When a photoreceptor is manufactured using the coating solution prepared in the above, the coated surface is likely to be whitened. It takes time to control the solid content of the coating liquid.
(2) For solvents other than halogenated aliphatic hydrocarbons, it is partially soluble in tetrahydrofuran, dioxane, cyclohexanone or a mixed solvent thereof, but the solution gels in a few days and has a time-dependent property. It is not suitable for photoconductor production.
(3) Even if the above (1) and (2) are improved, solvent cracks are liable to occur in the polycarbonate resin having bisphenol A as a skeleton.
(4) In addition, in the case of a conventional polycarbonate resin, the coating formed of the resin does not have lubricity, so that the photosensitive member is easily damaged, and an image is not formed in a cleaning setting that reduces the wear amount of the electrophotographic photosensitive member. or it becomes defective, cleaning failure due to premature deterioration of the cleaning blade, toner fusion, etc. had to be or Tsu island occurred.
[0007]
Wherein (1), in for example a solution stability, use of a polycarbonate Z resin having a bulky cyclohexylene group as the configuration units of the polymer, bisphenol Z, by copolymerizing a bisphenol C, etc. (2) It has been solved.
[0008]
On the other hand, polyarylate has a structure similar to that of polycarbonate, but differs in various properties. For example, although the mechanical strength is superior, the solubility of bisphenol Z type having a cyclohexylidene group is low. Also, there are differences in electrophotographic photoreceptor characteristics, and particularly when used as a binder resin for a charge transport layer, each memory, residual potential, and the like are liable to change (deterioration) depending on the structure of the charge transport material used.
[0009]
Solvent cracks can also be solved by using silicon-modified polycarbonate and ether-modified polycarbonate as disclosed in JP-A-6-51544 and JP-A-6-75415. However, these modified polycarbonates have a structure that gives flexibility to internal stress in the polymer in order to prevent solvent cracks as compared with conventional polycarbonate resins. There was a disadvantage that the strength was reduced.
[0010]
Further, in recent years, a direct charging system in which a voltage is applied directly to a charging member and a charge is applied to an electrophotographic photosensitive member, as disclosed in JP-A-57-17826 and JP-A-58-40566, is mainly used. It is becoming. This is a method in which a roller-shaped charging member made of conductive rubber or the like is brought into direct contact with the electrophotographic photoreceptor to apply an electric charge. Compared to a scorotron or the like, the amount of generated ozone is extremely small. While about 80% of the current flowing through the container is wasted because it flows through the shield, direct charging has the advantage that there is no waste and this is very economical.
[0011]
[Problems to be solved by the invention]
However, direct charging is disadvantageous in that charging stability is extremely poor because of charging by discharging according to Paschen's rule. As a countermeasure, a so-called AC / DC charging system in which an AC voltage is superimposed on a DC voltage has been devised (JP-A-63-149668). Although this charging method has improved the stability during charging, the amount of discharge on the surface of the electrophotographic photosensitive member is greatly increased due to the superposition of AC, and the shaving amount of the electrophotographic photosensitive member is increased. As a result, not only mechanical strength but also electrical strength has been required. In addition, it has become necessary to meet these requirements without deteriorating electrophotographic properties.
[0012]
An object of the present invention is to solve the conventional polycarbonate resin or polyarylate resin had a surface layer problem, strongly mechanical strength, Tsu manufacturing method der of electrophotographic characteristics good electrophotographic photoreceptor Te, and der that coating properties and coating pot life during manufacture to provide a process for producing an electrophotographic photosensitive member is good is, also, to provide an electrophotographic photosensitive member produced by the production method There is .
[0013]
Another object of the present invention is to provide a process cartridge having the above electrophotographic photosensitive member.
[0014]
Still another object of the present invention is to provide an electrophotographic apparatus having the above electrophotographic photosensitive member.
[0015]
[Means for Solving the Problems]
That is , the present invention relates to a method for producing an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the surface layer of the electrophotographic photoreceptor has a polymer having a structural unit represented by the following formula (1). In a method for producing an electrophotographic photoreceptor containing arylate and a polycarbonate having a structural unit represented by the following formula (2) ,
Obtaining a mixed polymer solution by dissolving and mixing a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2) in a solvent;
By reprecipitating a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2) dissolved in the mixed polymer solution using a poor solvent, Obtaining a blend polymer of a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2);
Forming a surface layer of the electrophotographic photoreceptor using the blended polymer;
A method for producing an electrophotographic photoreceptor, comprising:
[0016]
[Omitted]

(X _1, the TansoHara frame other represents a single bond (R ₅ and R ₆ story during this), R ₁ to R ₄ is a hydrogen atom, a halogen atom, also be an alkyl group or substituted substituted It represents an aryl group which may, R _5, R ₆ is a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, there have by that R ₅ and R ₆ are attached shows an alkylidene group that is formed, R ₇ to R ₁₀ represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group.)
[0017]
[Of 8]

(X ₂ is TansoHara frame other is a single bond (R ₁₅ and R ₁₆ story during this), R ₁₁ to R ₁₄ is a hydrogen atom, a halogen atom, also be an alkyl group or substituted substituted indicates even aryl group, R _15, R ₁₆ is a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, there have by that R ₁₅ and R ₁₆ are bonded Indicate the alkylidene group formed.)
[0018]
Further, the present invention is an electrophotographic photoreceptor manufactured by the above manufacturing method.
[0019]
Further , the present invention is a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
In formulas (1) and (2), the halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and the like, the alkyl group includes a methyl group, an ethyl group, a propyl group and a butyl group, and the aryl group includes Represents a phenyl group, a naphthyl group or the like, and the cycloalkylidene group includes a cyclohexylidene group. Examples of the substituent which the alkyl group, the aryl group and the cycloalkylidene group may have include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a phenyl group, an aryl group such as a naphthyl group, a fluorine atom, Examples thereof include a halogen atom such as a chlorine atom and a bromine atom.
[0021]
Specific examples of the structural unit represented by the formula (1) are shown in Tables 1 to 5 , but the present invention is not limited to these.
[0022]
[ Table 1 ]

[0023]
[ Table 2 ]

[0024]
[ Table 3 ]

[0025]
[ Table 4 ]

[0026]
[ Table 5 ]

[0027]
The polymer having a constitutional unit represented by the formula (1) used in the present invention is usually used in a mixture of terephthalic acid chloride and isophthalic acid chloride for controlling solubility and rigidity. Interfacial polymerization can be carried out by stirring with various bisphenols in a solvent / water system below. That is, the formulas shown in Tables 1 to 5 are represented as a form prepared from a mixed system of terephthalic acid chloride and isophthalic acid chloride. However, the ratio of terephthalic acid chloride and isophthalic acid chloride is determined in consideration of the solubility of the polymer, and there is no established theory. However, care must be taken when the content of any chloride is 30 mol% or less, since the solubility of the synthesized polymer is extremely reduced. Usually, it is preferable to synthesize at a ratio of 1/1. In the electrophotographic photoreceptor of the present invention, even if the polymer is constituted by the same structural unit represented by the formula (1), the polymer is composed of two or more different types of structural units represented by the formula (1). It may be united.
[0028]
Tables 6 to 9 show specific examples of the structural unit represented by the formula (2), but the present invention is not limited to these.
[0029]
[ Table 6 ]

[0030]
[ Table 7 ]

[0031]
[ Table 8 ]

[0032]
[ Table 9 ]

[0033]
Further, a blend material obtained by dissolving and mixing a polyarylate having a structural unit represented by the formula (1) and a polycarbonate having a structural unit represented by the formula (2) in a solvent and reprecipitating with a poor solvent is used. by containing, it is possible the effect of the present invention to outgoing current. The dissolution-reprecipitation can be performed by a conventional method. For example, dichloromethane, in a solvent soluble dissolution such as chloro e Lum, sufficiently dissolve the polyarylate and polycarbonate. Next, the mixed polymer solution is reprecipitated from a poor solvent such as methanol or water to obtain a flocculent polymer. This is vacuum dried to obtain a blend material. This material has improved solubility and paint stability over each simply blended polyarylate / polycarbonate. This method is effective for any polyarylate / polycarbonate, but is particularly effective for improving the properties of bisphenol A-type polycarbonate (specific example 2-1) and bisphenol Z-type polyarylate (specific example 1-22) , which have poor solubility. It is a target.
[0034]
Although the detailed mechanism has not been fully elucidated, the polycarbonate structure and the polyarylate structure can be highly blended by preliminarily blending each polymer in a solution. It is presumed that it became easier to express new characteristics due to the intrusion.
[0035]
In addition, it is considered that by blending molecules having different structures, the crystallinity of each is broken, so that it is considered that the solubility in each solvent is improved, and furthermore, gelation during storage, etc. It is presumed that suppression has become possible.
[0036]
Further, the cause of the decrease in the electrophotographic characteristics is estimated as follows. Phthalic acid ester structure polyarylate is one of the factors that has excellent mechanical strength has been expected to be one of the traps cause carry earth by a combination of a charge transport material, polycarbonate is at the molecular level It is presumed that it is avoided by being present near the polyarylate. Furthermore, residual impurities (residual monomer, chloride, etc.) in the polymer is one of the deterioration factor properties, ease of purification by improving the solubility is increased in the blend system of the present invention, the electrophotographic characteristics It is considered that the deterioration of is suppressed.
[0037]
In the present invention, the viscosity average molecular weight of the polyarylate and the polycarbonate is preferably from 10,000 to 200,000, and particularly preferably from 15,000 to 100,000. The molecular weight of the polyarylate and the molecular weight of the polycarbonate are preferably the same, and the difference is preferably within 5,000.
[0038]
Furthermore, by containing a copolymer having a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4) , lubricity on the surface, solvent crack resistance and the like are further improved.
[0039]
[Omitted]

(R _{17 to} R ₂₂ represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, and n represents a positive integer.)
[0040]
[Of 10]

(X ₃ is TansoHara frame other is a single bond (R ₂₇ and R ₂₈ story during this), R ₂₃ to R ₂₆ is a hydrogen atom, a halogen atom, also be an alkyl group or substituted substituted It represents an aryl group which may, R _27, R ₂₈ is a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, there have by that R ₂₇ and R ₂₈ are bonded Indicate the alkylidene group formed.)
[0041]
In the formulas (3) and (4), examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. Represents a phenyl group, a naphthyl group or the like, and the cycloalkylidene group includes a cyclohexylidene group. Examples of the substituent which the alkyl group, the aryl group and the cycloalkylidene group may have include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a phenyl group, an aryl group such as a naphthyl group, a fluorine atom, Examples thereof include a halogen atom such as a chlorine atom and a bromine atom. n represents a positive integer and is preferably 1 to 200.
[0042]
Specific examples of the structural unit represented by the formula (3) in Table 10-12 is not limited thereto.
[0043]
[ Table 10 ]

[0044]
[ Table 11 ]

[0045]
[ Table 12 ]

[0046]
Since the expression (4) is the same as the expression (2) shown in Tables 6 to 9 , the examples of Tables 6 to 9 are applied to specific examples of Expression (4).
[0047]
This blend at the molecular level raises the intramolecular density, and also has an amorphous part and a crystalline part in the same molecule, so that the intramolecular stress generated at the time of coating film formation can also be relaxed, thereby reducing solvent cracking. It is presumed that internal stress is maintained and cracks do not occur even if a factoring chemical enters. Furthermore, by containing a polycarbonate which is a copolymer having a structural unit represented by the formula (3) and a structural unit represented by the formula (4), penetration of a solvent causing cracks can be prevented, and Can effectively improve the solvent crack resistance.
[0048]
Hereinafter , the configuration of the electrophotographic photosensitive member of the present invention will be described.
[0049]
In the electrophotographic photoreceptor of the present invention, the photosensitive layer may be a single-layer type containing a charge transport material and a charge generation material in the same layer, or a charge transport layer containing a charge transport material and a charge generation material. Although a laminated type in which the charge generation layer is separated may be used, a laminated type is preferable from the viewpoint of electrophotographic characteristics. In either case, the surface layer of at least the electrophotographic photosensitive member contains a polycarbonate having a polyarylate having a structural unit represented by the formula (1), a structural unit represented by the formula (2).
[0050]
The conductive support to be used is not limited as long as it has conductivity, and may be a metal such as aluminum or stainless steel, or a metal provided with a conductive layer, paper, plastic, or the like. No. In particular, when an image input such as LBP is a laser beam, it is preferable to provide a conductive layer for the purpose of preventing interference fringes due to scattering or covering a scratch on the support. This can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The thickness of the conductive layer is 5 to 40 μm, preferably 10 to 30 μm.
[0051]
An intermediate layer having an adhesive function and a barrier function can be provided thereon as needed. Examples of the material for the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, polyether urethane, and the like. These are applied by dissolving in an appropriate solvent. The intermediate layer has a thickness of 0.05 to 5 μm, preferably 0.3 to 1 μm.
[0052]
In the case of the function separation type, a charge generation layer is formed thereon. As the charge generating material used in the present invention, selenium-tellurium, pyrylium, thiapyrylium-based dye, phthalocyanine, anthantrone, dibenzpyrenequinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone, asymmetric quinocyanine-based pigments No. The charge generation layer uses a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill, a liquid collision type high-speed disperser, and the like, with the charge generation material in an amount of 0.3 to 4 times the amount of a binder resin and a solvent. It is formed by applying a dispersion and drying. The thickness of the charge generation layer is 5 μm or less, preferably 0.1 to 2 μm.
[0053]
The charge transport layer is formed by applying and drying a paint in which a charge transport material and a binder resin are dissolved in a solvent. Examples of the charge transport material used include a triarylamine compound, a hydrazone compound, a stilbene compound, a pyrazoline compound, an oxazole compound, a triallylmethane compound, and a thiazole compound.
[0054]
These are combined with 0.5 to 2 times the amount of the binder resin, applied and dried to form a charge transport layer. The thickness of the charge transport layer is 5 to 40 μm, preferably 15 to 30 μm.
[0055]
When the photosensitive layer is of a single-layer type, the photosensitive layer is formed by applying and drying a solution in which the above-described charge generation material or charge transport material is dispersed and dissolved in the above-described binder resin. The film thickness is suitably from 5 to 40 μm, preferably from 15 to 30 μm.
[0056]
FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.
[0057]
In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around an axis 2 at a predetermined peripheral speed in a direction indicated by an arrow. In the rotation process, the photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on the peripheral surface thereof by the primary charging means 3, and then receives a charge from an image exposure means (not shown) such as slit exposure or laser beam scanning exposure. It receives image exposure light 4. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.
[0058]
The formed electrostatic latent image is then subjected to toner development by the developing unit 5, and the developed toner developed image is transferred between the photoconductor 1 and the transfer unit 6 by a rotation of the photoconductor 1 from a feeding unit (not shown). The transfer material 6 is sequentially transferred to the transfer material 7 taken out and fed synchronously.
[0059]
The transfer material 7 that has 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.
[0060]
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.
[0061]
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 a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, which can be attached to and detached from the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. The process cartridge 11 can be used.
[0062]
When the electrophotographic apparatus is a copier or a printer, the image exposure light 4 is reflected light or transmitted light from the original, or the original is read by a sensor and converted into a signal, and a laser beam is emitted according to the signal. Light emitted by scanning, driving of an LED array, driving of a liquid crystal shutter array, and the like.
[0063]
The electrophotographic photoreceptor of the present invention can be widely used not only for electrophotographic copying machines but also for electrophotographic applications such as laser beam printers, CRT printers, LED printers, liquid crystal printers, and laser plate making.
[0064]
Hereinafter , description will be made according to examples.
[0065]
【Example】
First, a method for synthesizing the polyarylate and the polycarbonate used in the present invention will be described, but the method is not limited thereto.
[0066]
Polyarylate having structural units of formula (1) are sodium hydroxide predetermined bisphenol 0.01 mol 0.8 g, was dissolved tetramethylammonium chloride 1g of water 100 ml, it was poured into 1 liter mixer A solution prepared by dissolving 0.005 mol of terephthalic acid chloride and 0.005 mol of isophthalic acid chloride in 30 ml of 1,2-dichloroethane was added thereto with stirring, and the mixture was stirred at a high speed for 10 minutes. -A dichloroethane solution was recovered, a large amount of hexane was added thereto, and recovered as a polymer.
[0067]
The polycarbonate having the structural unit represented by the formula (2) was synthesized from a predetermined bisphenol and phosgene by an ordinary method.
[0068]
Furthermore, in the present invention, a method of blending the polyarylate and polycarbonate is how to blend reprecipitated in a poor solvent was dissolved in Solvent. As a procedure, first, polyarylate / polycarbonate = 1/1 (wt) was sufficiently dissolved in 10-fold amount (wt) of dichloromethane. Then, the polymer solution was gradually added dropwise while stirring methanol 10 times the amount (wt) of the dissolving solvent. A white flocculent blend polymer was obtained in this methanol. This was vacuum-dried and used as flakes.
[0069]
[Example 1]
An Al cylinder having a diameter of 30 mm and a diameter of 254 mm was used as a support, and a coating composed of the following materials was applied on the support by an immersion method, and heat-cured at 140 ° C. for 30 minutes to form a conductive layer having a thickness of 15 μm.
[0070]
Conductive pigment: SnO ₂ coated barium sulfate 10 parts Resistance adjusting pigment: titanium oxide 2 parts Binder resin: phenol resin 6 parts Leveling material: silicone oil 0.001 parts Solvent: methanol, methoxypropanol 0.2 / 0.8 20 copies
Next , a solution obtained by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymer nylon in a mixed solvent of 65 parts of methanol and 30 parts of n-butanol was applied on the conductive layer by a dipping method. An intermediate layer of 0.5 μm was formed.
[0072]
Next , 4 parts of TiOPc having strong peaks at 9.0 °, 14.2 °, 23.9 °, and 27.1 ° in the diffraction angle 2θ ± 0.2 ° in CuKα X-ray diffraction and polyvinyl butyral (trade name) : Esrec BM2, manufactured by Sekisui Chemical Co., Ltd.) and 2 parts of cyclohexanone were dispersed in a sand mill using φ1 mm glass beads for 4 hours, and then 100 parts of ethyl acetate was added to prepare a dispersion for a charge generation layer. This was applied by a dipping method to form a charge generation layer having a thickness of 0.3 μm.
[0073]
Next, in order to form a charge transport layer, a paint for the charge transport layer was prepared. As polymer blend used was prepared by blending the dissolution / reprecipitation and polycarbonate polyarylate and bisphenol A (Examples 2-1) of bisphenol A (Examples 1-1). The blended polymer 10 parts, 9 parts following structural formula of the amine compound and [0074]
[Of 11]

1 part of an amine compound having the following structural formula ,
[0075]
[Of 12]

It was dissolved in mono chlorobenzene 50 parts of a mixed solvent of 50 parts of dichloromethane. This paint was applied by a dipping method and dried at 120 ° C. for 2 hours to form a 25 μm charge transport layer.
[0076]
Next, evaluation will be described.
[0077]
The apparatus was modified from Hewlett-Packard's LBP "Laser Jet 4plus" (process speed: 71 mm / sec). The remodeling was performed with pre-exposure using a fuse lamp attached immediately before the charger, so that the lamp was turned on only when measuring the residual potential. The potential measurement was performed by setting the dark part to Vd, the laser light irradiation part to Vl, and the pre-exposure irradiation part to Vr. The prepared electrophotographic photosensitive member was subjected to paper passing durability at 23 ° C. and 55% RH using this apparatus. The sequence was an intermittent mode in which the print was stopped once for each print, and 5,000 prints were endured. Further, for the solvent cracking property, finger grease was adhered to the surface and allowed to stand for 24 hours, and the presence or absence of solvent cracking was observed under a microscope. As an evaluation of the pot life, each charge transport layer coating was allowed to stand in a closed container at room temperature (23 ° C.) for one week, and the dissolved state was observed.
[0078]
[Example 2]
In Example 1, as a blend polymer used was prepared by blending the dissolution / reprecipitation and polycarbonate polyarylate and bisphenol Z (Examples 2-13) of bisphenol Z-type (Examples 1-2 2) Except that it was prepared in the same manner.
[0079]
[Comparative Example 1]
In Example 1, the charge transport layer binder resin of bisphenol Z-type for it except that only a polyarylate (Examples 1-22) was so prepared in the same manner, the polymer is dissolved in sufficient solvent to be used As a result, a coating for the charge transport layer could not be prepared, and a photoreceptor could not be prepared.
[0080]
[Comparative Example 2 ]
In the same manner as in Example 1, except that the binder resin for the charge transport layer used was only bisphenol A type (specific example 2-1) polycarbonate.
[0081]
[ Reference Example 1 ]
In the same manner as in Example 1, except that the binder resin for the charge transport layer used was only bisphenol A type (specific example 1-1) polyarylate.
[0082]
[ Reference Example 2 ]
In the same manner as in Example 1, except that the binder resin for the charge transporting layer used was only bisphenol Z type (specific example 2-13) polycarbonate.
[0083]
Above Examples 1 and 2 and Comparative Examples 1 and 2 and Reference Examples 1 and 2, shown in Table 13 below summarizes the seeds Rui及 beauty properties of the binder resin for the charge transporting layer.
[0084]
[ Table 13 ]

[0085]
As described above, by adding polycarbonate to a specific polyarylate, it is possible to improve electrophotographic properties while substantially maintaining abrasion resistance. Further, conventionally, there has been a limitation on constituent units that can be used from the viewpoint of solubility and pot life, but the present invention can improve the solubility, and therefore, the characteristics (mechanical strength, electrophotographic characteristics, etc.) of the photoreceptor can be improved. Can be selected and used with priority.
[0086]
【The invention's effect】
As described above, the electrophotographic photoreceptor of the present invention has excellent mechanical strength of polyarylate and good electrophotographic properties of polycarbonate. In addition, the improvement of solubility and pot life has expanded the range of choice of materials (constituent units), and it has become possible to provide an electrophotographic photosensitive member according to the purpose of use.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having a process cartridge having an electrophotographic photosensitive member of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electrophotographic photosensitive member 2 of this invention 2 Axis 3 Primary charging means 4 Image exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 Rail

Claims (10)

A method for producing an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the surface layer of the electrophotographic photosensitive member has a polyarylate having a structural unit represented by the following formula (1) and a polyarylate having the following formula (2) In the method for producing an electrophotographic photoreceptor containing a polycarbonate having the structural unit represented by
Obtaining a mixed polymer solution by dissolving and mixing a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2) in a solvent;
By reprecipitating a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2) dissolved in the mixed polymer solution using a poor solvent, Obtaining a blend polymer of a polyarylate having a structural unit represented by the following formula (1) and a polycarbonate having a structural unit represented by the following formula (2);
Forming a surface layer of the electrophotographic photoreceptor using a paint containing the blend polymer and a solvent,
A method for producing an electrophotographic photosensitive member, comprising:

(X _1, the TansoHara frame other represents a single bond (R ₅ and R ₆ story during this), R ₁ to R ₄ is a hydrogen atom, a halogen atom, also be an alkyl group or substituted substituted It represents an aryl group which may, R _5, R ₆ is a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, there have by that R ₅ and R ₆ are attached shows an alkylidene group that is formed, R ₇ to R ₁₀ represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group.)

(X ₂ is TansoHara frame other is a single bond (R ₁₅ and R ₁₆ story during this), R ₁₁ to R ₁₄ is a hydrogen atom, a halogen atom, also be an alkyl group or substituted substituted indicates even aryl group, R _15, R ₁₆ is a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an optionally substituted aryl group, there have by that R ₁₅ and R ₁₆ are bonded Indicate the alkylidene group formed.) The electrophotographic apparatus according to claim 1, wherein the polyarylate having the structural unit represented by the formula (1) is a polyarylate having the structural unit represented by the following formula (1-22). Manufacturing method of photoreceptor.

The method for producing an electrophotographic photosensitive member according to claim 2, wherein the polycarbonate having a structural unit represented by the formula (2) is a polycarbonate having a structural unit represented by the following formula (2-13).

The method for producing an electrophotographic photoreceptor according to claim 1, wherein the polycarbonate having a structural unit represented by the formula (2) is a polycarbonate having a structural unit represented by the following formula (2-1).

The method for producing an electrophotographic photoreceptor according to claim 4, wherein the polyarylate having the structural unit represented by the formula (1) is a polyarylate having the structural unit represented by the following formula (1-1).

The solvent used in the step of obtaining the mixed polymer solution is a halogenated aliphatic hydrocarbon, and the solvent contained in the coating used in the step of forming a surface layer of the electrophotographic photoreceptor is a halogenated fatty acid. The method for producing an electrophotographic photoreceptor according to any one of claims 2 to 5, which is a solvent containing a solvent other than aromatic hydrocarbons. The solvent used in the step of obtaining the mixed polymer solution is dichloromethane, and the solvent contained in the coating used in the step of forming the surface layer of the electrophotographic photoreceptor is a mixed solvent of monochlorobenzene and dichloromethane. The method for producing an electrophotographic photosensitive member according to claim 3 or 5. An electrophotographic photosensitive member manufactured by the manufacturing method according to claim 1. An electrophotographic photosensitive member according to claim 8, charging means, and at least one means selected from the group consisting of the developing means and cleaning means integrally supported, the process cartridge is detachably mountable to an electrophotographic apparatus main body. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 8 , a charging unit, an image exposing unit, a developing unit, and a transfer unit.

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