JP3718589B2 - Electrophotographic photoreceptor - Google Patents

Description

【００１４】
一般式（１）、において、Ａは、置換基を有しても良いアルケニル基。Ｒ¹ 、Ｒ²は、水素原子、アルキル基、アルケニル基、アラルキル基、アリール基、複素環基を示し、置換基を有していても良い。Ｒ³は、アルキル基、アリール基 、複素環基を示し、置換基を有していても良い。但し、Ｒ ³ は、置換基を有していてもよいベンジル基を除く。Ａｒ ¹ は、メチレン基、アリーレン基を示し、置換基を有していても良い。Ａｒ²は、アリーレン基を示し、置換基を有しても良い。
【００１５】
Ａの具体例としては、ビニル基、アリル基、プロペニル基、２−ブテニル基、２−メチルアリル基、スチリル基、シンナミル基等のアルケニル基が挙げられる。Ｒ¹の具体例としては、水素原子、メチル基、エチル基、プロピル基等のアル キル基、アリル基、メタリル基、２−メチル−１−プロペニル基等のアルケニル基、ベンジル基、α−ナフチルメチル基、β−フェニチルエチル基等のアラルキル基、フェニル基、ナフチル基等のアリール基、チエニル基、フリル基、ピロリル基、ピラニル基、ピリジル基等の複素環基を挙げることができ、これらは置環基を有していても良い。置換基の例としては、フッ素原子、塩素原子、臭素原子等のハロゲン原子、メトキシ基、エトキシ基、プロポキシ基等のアルコキシ基、フェノキシ基等のアリールオキシ基、上述のアルキル基、アリール基、アラルキル基を挙げることができる。Ｒ²の具体例としては、上述したアルキル基、アラルキル基、アリール基、複素環基を示し、これらは上述した置換基を有していても良い。Ｒ³の具体例としては、ベンジル基を除く上述したアルキル基、アリール基、複素環基を示し、これらは上述した置換基を有していても良い。
【００１６】
Ａｒ ¹ の具体例としては、メチレン基、ｏ−フェニレン基、ｍ−フェニレン基 、ｐ−フェニレン基等のフェニレン基、ナフチレン基、フェナンスリレン基等のアリーレン基を挙げることができる。Ａｒ²の具体例としては、メチレン基、上述した アリーレン基が挙げられる。
【００１７】
【発明の実施の形態】
本発明に係わる一般式（１）で示されるビススチルベン化合物の具体例を以下に例示するが、これらに限定されるものではない。
【００１８】
【化３】

【００１９】
【化４】

【００２０】
【化５】

【００２１】
【化６】

【００２２】
【化７】

【００２３】
【化８】

【００２４】
感光体の形態としては種々のものがあるが、本発明はそのいずれの形態においても用いることができる。例えば、導電性支持体上に光導電性物質である電荷発生物質、電荷輸送物質、およびフィルム形成性結着剤樹脂からなる感光層を設けた単層型感光体、導電性支持体上に電荷発生物質と結着剤樹脂からなる電荷発生層と、電荷輸送物質と結着剤樹脂からなる電荷輸送層を設けた積層型の感光体が挙げられる。電荷発生層と電荷輸送層はどちらが上層となっても構わない。また、必要に応じて導電性支持体と感光層の間に下引き層を、感光体表面にオーバーコート層を、積層型感光体の場合は電荷発生層と電荷輸送層との間に中間層を設けることもできる。本発明に係わる化合物を用いて感光体を作製する支持体としては、金属製ドラム、金属板、導電性加工を施した紙、プラスチックフィルムのシート状、ドラム状あるいはベルト状の支持体等が使用される。
【００２５】
本発明に用いる電荷発生物質としては、セレン、カドミウム等の金属や、ペリレン酸無水物、ペリレン酸イミド等のペリレン化合物、アントラキノン誘導体、アンスアンスロン誘導体、ジベンズピレンキノン誘導体、ピラントロン誘導体、ビオラントロン誘導体等のアントラキノン顔料または多環キノン顔料、金属フタロシアニン、無金属フタロシアニン等のフタロシアニン化合物、金属ナフタロシアニン、無金属ナフタロシアニン等のナフタロシアニン化合物、ポルフィリン顔料、キナクリドン顔料、シアニン色素、アズレニウム色素等、また、アゾ化合物も用いられる。なかでも、ビスアゾ化合物、トリスアゾ化合物、フタロシアニン化合物を用いたものは、キャリア発生効率が高く、高感度の感光体を提供するため好ましい。
【００２６】
例えばアゾ化合物としては、特開昭４７−３７５４３号、特開昭５３−９５０３３号、特開昭５３−１３２３４７号、特開昭５３−１３３４４５号、特開昭５４−１２７４２号、特開昭５４−２０７３６号、特開昭５４−２０７３７号、特開昭５４−２１７２８号、特開昭５４−２２８３４号、特開昭５５−６９１４８号、特開昭５５−６９６５４号、特開昭５５−７９４４９号、特開昭５５−１１７１５１号、特開昭５６−４６２３７号、特開昭５６−１１６０３９号、特開昭５６−１１６０４０号、特開昭５６−１１９１３４号、特開昭５６−１４３４３７号、特開昭５７−６３５３７号、特開昭５７−６３５３８号、特開昭５７−６３５４１号、特開昭５７−６３５４２号、特開昭５７−６３５４９号、特開昭５７−６６４３８号、特開昭５７−７４７４６号、特開昭５７−７８５４２号、特開昭５７−７８５４３号、特開昭５７−９００５６号、特開昭５７−９００５７号、特開昭５７−９０６３２号、特開昭５７−１１６３４５号、特開昭５７−２０２３４９号、特開昭５８−４１５１号、特開昭５８−９０６４４号、特開昭５８−１４４３５８号、特開昭５８−１７７９５５号、特開昭５９−３１９６２号、特開昭５９−３３２５３号、特開昭５９−７１０５９号、特開昭５９−７２４４８号、特開昭５９−７８３５６号、特開昭５９−１３６３５１号、特開昭５９−２０１０６０号、特開昭６０−１５６４２号、特開昭６０−１４０３５１号、特開昭６０−１７９７４６号、特開昭６１−１１７５４号、特開昭６１−９０１６４号、特開昭６１−９０１６５号、特開昭６１−９０１６６号、特開昭６１−１１２１５４号、特開昭６１−２８１２４５号、特開昭６１−５１０６３号、特開昭６２−２６７３６３号、特開昭６３−６８８４４号、特開昭６３−８９８６６号、特開昭６３−１３９３５５号、特開昭６３−１４２０６３号、特開昭６３−１８３４５０号、特開昭６３−２８２７４３号、特開昭６４−２１４５５号、特開昭６４−７８２５９号、特開平１−２００２６７号、特開平１−２０２７５７号、特開平１−３１９７５４号、特開平２−７２３７２号、特開平２−２５４４６７号、特開平３−２７８０６３号、特開平４−９６０６８号、特開平４−９６０６９号、特開平４−１４７２６５号、特開平５−１４２８４１号、特開平５−３０３２２６号、特開平６−３２４５０４号、特開平７−１６８３７９号公報に記載の化合物が挙げられる。
【００２７】
上記アゾ化合物の具体例として、以下の表に示す化合物が挙げられるが、これらに限定されるものではない。また、これらの化合物と他の電荷発生物質を併用することも可能である。
【００２８】
【表１】

【００２９】
【表２】

【００３０】
【表３】

【００３１】
【表４】

【００３２】
【表５】

【００３３】
【表６】

【００３４】
【表７】

【００３５】
【表８】

【００３６】
【表９】

【００３７】
【表１０】

【００３８】
【表１１】

【００３９】
【表１２】

【００４０】
【表１３】

【００４１】
【表１４】

【００４２】
【表１５】

【００４３】
【表１６】

【００４４】
【表１７】

【００４５】
【表１８】

【００４６】
【表１９】

【００４７】
【表２０】

【００４８】
【表２１】

【００４９】
【表２２】

【００５０】
【表２３】

【００５１】
【表２４】

【００５２】
【表２５】

【００５３】
【表２６】

【００５４】
【表２７】

【００５５】
【表２８】

【００５６】
【表２９】

【００５７】
【表３０】

【００５８】
【表３１】

【００５９】
【表３２】

【００６０】
【表３３】

【００６１】
【表３４】

【００６２】
【表３５】

【００６３】
【表３６】

【００６４】
【表３７】

【００６５】
【表３８】

【００６６】
【表３９】

【００６７】
【表４０】

【００６８】
【表４１】

【００６９】
【表４２】

【００７０】
【表４３】

【００７１】
【表４４】

【００７２】
【表４５】

【００７３】
また、例えばフタロシアニン化合物であれば、無金属フタロシアニン類、チタニルオキシフタロシアニン類、銅フタロシアニン類、アルミニウムフタロシアニン類、ゲルマニウムフタロシアニン類、クロロガリウムフタロシアニン類、クロロインジウムフタロシアニン類、マグネシウムフタロシアニン類、クロロアルミニウムフタロシアニン類、スズフタロシアニン類、バナジルオキシフタロシアニン類、ガリウムフタロシアニン類、亜鉛フタロシアニン類、コバルトフタロシアニン類、ニッケルフタロシアニン類、ヒドロキシガリウムフタロシアニン類、ジクロロチタニルフタロシアニン類、ジフェノキシゲルマニウムフタロシアニン類等が挙げられる。
【００７４】
本発明に係わる支持体上へ、感光層を形成するために用いるフィルム形成性結着剤樹脂としては、利用分野に応じて種々のものがあげられる。例えば複写用感光体の用途では、ポリ塩化ビニル樹脂、ポリスチレン樹脂、ポリビニルアセタール樹脂、ポリスルホン樹脂、ポリカーボネート樹脂、酢ビ・クロトン酸共重合体樹脂、ポリエステル樹脂、ポリフェニレンオキサイド樹脂、ポリアリレート樹脂、アルキッド樹脂、アクリル樹脂、メタクリル樹脂、フェノキシ樹脂等が挙げられる。これらの中でも、ポリスチレン樹脂、ポリビニルアセタール樹脂、ポリカーボネート樹脂、ポリエステル樹脂、ポリアリレート樹脂等は感光体としての電位特性に優れている。又、これらの樹脂は、単独あるいは共重合体として１種又は２種以上を混合して用いることができる。これら結着剤樹脂の光導電性物質に対して加える量は、２０〜１０００重量％が好ましく、５０〜５００重量％がより好ましい。
【００７５】
積層型感光体の場合、電荷発生層に含有されるこれらの樹脂は、電荷発生物質に対して１０〜５００重量％が好ましく、５０〜１５０重量％がより好ましい。樹脂の比率が高くなりすぎると電荷発生効率が低下し、また樹脂の比率が低くなりすぎると成膜性に問題が生じる。また、電荷輸送層に含有されるこれらの樹脂は、電荷輸送物質に対して２０〜１０００重量％が好ましく、５０〜５００重量％がより好ましい。樹脂の比率が高すぎると感度が低下し、また、樹脂の比率が低くなりすぎると繰り返し特性の悪化や塗膜の欠損を招くおそれがある。
【００７６】
これらの樹脂の中には、引っ張り、曲げ、圧縮等の機械的強度に弱いものがある。この性質を改良するために、可塑性を与える物質を加えることができる。具体的には、フタル酸エステル（例えばＤＯＰ、ＤＢＰ等）、リン酸エステル（例えばＴＣＰ、ＴＯＰ等）、セバシン酸エステル、アジピン酸エステル、ニトリルゴム、塩素化炭化水素等が挙げられる。これらの物質は、必要以上に添加すると電子写真特性の悪影響を及ぼすので、その割合は結着剤樹脂に対し２０重量％以下が好ましい。
【００７７】
その他、感光体中への添加物として酸化防止剤やカール防止剤等、塗工性の改良のためレベリング剤等を必要に応じて添加することができる。
【００７８】
一般式（１）で示される化合物は、更に他の電荷輸送物質と組み合わせて用いることができる。電荷輸送物質には正孔輸送物質と電子輸送物質がある。前者の例としては、例えば特公昭３４−５４６６号公報等に示されているオキサジアゾール類、特公昭４５−５５５号公報等に示されているトリフェニルメタン類、特公昭５２−４１８８号公報等に示されているピラゾリン類、特公昭５５−４２３８０号公報等に示されているヒドラゾン類、特開昭５６−１２３５４４号公報等に示されているオキサジアゾール類等を挙げることができる。一方、電子輸送物質としては、例えばクロラニル、テトラシアノエチレン、テトラシアノキノジメタン、２，４，７−トリニトロ−９−フルオレノン、２，４，５，７−テトラニトロ−９−フルオレノン、２，４，５，７−テトラニトロキサントン、２，４，８−トリニトロチオキサントン、１，３，７−トリニトロジベンゾチオフェン、１，３，７−トリニトロジベンゾチオフェン−５，５−ジオキシド等がある。これらの電荷輸送物質は単独または２種以上組み合わせて用いることができる。
【００７９】
また、本発明に係わる有機系の光導電性物質と電荷移動錯体を形成し、更に増感効果を増大させる増感剤として、ある種の電子吸引性化合物を添加することもできる。この電子吸引性化合物としては、例えば、２，３−ジクロロ−１，４−ナフトキノン、１−ニトロアントラキノン、１−クロロ−５−ニトロアントラキノン、２−クロロアントラキノン、フェナントレンキノン等のキノン類、４−ニトロベンズアルデヒド等のアルデヒド類、９−ベンゾイルアントラセン、インダンジオン、３，５−ジニトロベンゾフェノン、３，３′，５，５′−テトラニトロベンゾフェノン等のケトン類、無水フタル酸、４−クロロナフタル酸無水物等の酸無水物、テレフタラルマロノニトリル、９−アントリルメチリデンマロノニトリル、４−ニトロベンザルマロノニトリル、４−（ｐ−ニトロベンゾイルオキシ）ベンザルマロノニトリル等のシアノ化合物、３−ベンザルフタリド、３−（α−シアノ−ｐ−ニトロベンザル）フタリド、３−（α−シアノ−ｐ−ニトロベンザル）−４，５，６，７−テトラクロロフタリド等のフタリド類等を挙げることができる。
【００８０】
本発明に係わる有機系の光導電性物質は、感光体の形態に応じて上記の種々の添加物質と共に適当な溶剤中に溶解又は分散し、その塗布液を先に述べた導電性支持体上に塗布し、乾燥して感光体を製造することができる。
【００８１】
塗布溶剤としては、クロロホルム、ジクロロエタン、ジクロロメタン、トリクロロエタン、トリクロロエチレン、クロロベンゼン、ジクロロベンゼン等のハロゲン化炭化水素、ベンゼン、トルエン、キシレン等の芳香族炭化水素、ジオキサン、テトラヒドロフラン、メチルセロソルブ、エチルセロソルブ、エチレングリコールジメチルエーテル等のエーテル系溶剤、メチルエチルケトン、メチルイソブチルケトン、メチルイソプロピルケトン、シクロヘキサノン等のケトン系溶剤、酢酸エチル、蟻酸メチル、メチルセロソルブアセテート等のエステル系溶剤、Ｎ，Ｎ−ジメチルホルムアミド、アセトニトリル、Ｎ−メチルピロリドン、ジメチルスルホキシド等の非プロトン性極性溶剤及びアルコール系溶剤等を挙げることができる。これらの溶剤は、単独または２種以上の混合溶剤として使用することができる。
【００８２】
【実施例】
次に本発明を実施例によりさらに詳細に説明するが、本発明はこれらに何ら限定されるものではない。
【００８３】
実施例１
電荷発生物質（例示化合物Ｋ−１）を１重量部とポリビニルブチラール樹脂（電気化学工業製、デンカブチラール＃３０００−Ｋ）１重量部を１，２−ジメトキシエタン１００重量部に混合し、ペイントコンディショナーによりガラスビーズと共に４時間分散した。こうして得た分散液をアプリケーターにて、アルミ蒸着ポリエステル上に塗布して、膜厚約０．４μｍの電荷発生層を形成した。次にビススチルベン化合物（例示化合物ＣＴ−３）１０重量部、ポリカーボネート樹脂（帝人化成製、パンライトＣ−１３００）１０重量部、２，５−ジ−ｔ−ブチルハイドロキノン（以下ＴＢＨと略す）０．２重量部をジクロロメタン１５０重量部に溶解し、上記電荷発生層の上にアプリケーターで塗布して、膜厚約２０μｍの電荷輸送層を形成した。
【００８４】
このようにして作製した積層型感光体を、室温暗中に一昼夜保管した後、静電記録試験装置（川口電機製、ＳＰ−４２８）により電子写真特性評価を行なった。
測定条件：印加電圧−６ｋＶ、スタティックNo.３（ターンテーブルの回転スピードモード：１０ｍ／ｍｉｎ ）、照射光照度２ルックス。
その結果、帯電電位Ｖ0が−８３５Ｖ、半減露光量Ｅ１／２が０．８８ルックス・秒と高感度の値を示した。
【００８５】
次にこの感光体をアルミニウム製のドラム素管に張り付け、ドラム感光体評価装置（ジェンテック製、シンシア９０）により帯電及び光除電の繰り返し特性を評価した。
測定条件：コロナ印加電圧−５．２ｋＶ、プロセス速度１６０ｍｍ／ｓ、ＴＣＣＤモード２、光除電：タングステンランプアレイ。
帯電後の表面電位（帯電電位Ｖ0）及び光除電後の表面電位（残留電位Ｖｒ）は１回目の帯電電位Ｖ0が−８４３Ｖ、残留電位Ｖｒが−４７Ｖに対し、５０００回目の帯電電位Ｖ0は−８５６Ｖ、残留電位Ｖｒは−４６Ｖであり、繰り返しによる変化が極めて少ないことがわかった。
【００８６】
実施例２〜９
実施例１のビススチルベン化合物（例示化合物ＣＴ−３）の代わりにそれぞれ表４６に示す化合物を用いる他は、実施例１と同様にして感光体を作製してその特性を評価した。半減露光量Ｅ１／２、１回目と５０００回目の帯電電位の差（ΔＶ0）及び残留電位の差（ΔＶｒ）を表４６に示す。
【００８７】
【表４６】

【００８８】
実施例１０〜１６
実施例１の電荷発生物質（例示化合物Ｋ−１）及び電荷輸送物質（例示化合物ＣＴ−３）の代わりにそれぞれ表４７に示す例示化合物を用いた他は、実施例１と同様にして感光体を作製してその特性を評価した。結果を表４７に示す。
【００８９】
【表４７】

【００９０】
実施例１７
Ｘ型無金属フタロシアニン１重量部及びポリエステル樹脂（東洋紡製、バイロン２２０）１重量部をジオキサン１００重量部と混合し、ペイントコンディショナー装置でガラスビーズと共に３時間分散した。こうして得た分散液を、アプリケーターにてアルミ蒸着ポリエステル上に塗布して乾燥し、膜厚約０．２μｍの電荷発生層を形成した。次にビススチルベン化合物（例示化合物ＣＴ−３）を、ポリアリレート樹脂（ユニチカ製、Ｕ−ポリマー）と１：１の重量比で混合し、ジクロロエタンを溶媒として１０重量％の溶液を作り、上記の電荷発生層の上にアプリケーターで塗布して膜厚約２０μｍの電荷輸送層を形成した。
【００９１】
この様にして作製した積層型感光体について、静電記録試験装置（川口電機製ＳＰ−４２８）を用いて電子写真特性の評価を行なった。
測定条件：印加電圧−６ｋＶ、スタティックNo. ３（ターンテーブルの回転スピードモード：１０ｍ／ｍｉｎ ）。その結果、帯電電位（Ｖ0）が−７７６Ｖ、半減露光量（Ｅ1/2）が１．１ルックス・秒と高感度の値を示した。
【００９２】
更に同装置を用いて、帯電−除電（除電光：白色光で４００ルックス×１秒照射）を１サイクルとする繰返し使用に対する特性評価を行った。５０００回での繰返しによる帯電電位の変化を求めたところ、１回目の帯電電位（Ｖ0）−７９５Ｖに対し、５０００回目の帯電電位（Ｖ0）は−７９０Ｖであり、繰返しによる電位の低下が少なく安定した特性を示した。また、１回目の半減露光量（Ｅ1/2）１．１ルックス・秒に対して５０００回目の半減露光量（Ｅ1/2）は１．１ルックス・秒と変化がなく、優れた特性を示した。
【００９３】
実施例１８〜２５
実施例１７の電荷輸送物質（例示化合物ＣＴ−３）の代わりに、それぞれ表４８に示す例示化合物を用いた他は、実施例１７と同様にして感光体を作製してその特性を評価した。結果を表４８に示す。
【００９４】
【表４８】

【００９５】
以下の実施例および比較例で用いたフタロシアニンのＸ線回折スペクトルにおけるピーク位置、および表中で用いた略号を表４９に示す。
【００９６】
【表４９】

【００９７】
実施例２６〜３９
実施例１７の電荷発生物質（Ｘ型無金属フタロシアニン）及び電荷輸送物質（例示化合物ＣＴ−３）の代わりに、それぞれ表５０、表５１に示す例示化合物を用いた他は、実施例１７と同様にして感光体を作製してその特性を評価した。結果を表５０、表５１に示す。
【００９８】
【表５０】

【００９９】
【表５１】

【０１００】
実施例４０
Ｘ型無金属フタロシアニン１重量部とテトラヒドロフラン４０重量部を、ペイントコンディショナー装置でガラスビーズと共に４時間分散処理した。こうして得た分散液に、ビススチルベン化合物（例示化合物ＣＴ−３）を２．５重量部、ポリカーボネート樹脂（三菱ガス化学製、ＰＣＺ−２００）１０重量部、テトラヒドロフラン６０重量部を加え、さらにペイントコンディショナー装置で３０分間分散処理を行った後、アプリケーターにてアルミ蒸着ポリエステル上に塗布し、膜厚約１５μｍの感光体を形成した。この感光体の電子写真特性を、実施例１と同様にして評価した。ただし、印加電圧のみ＋５ｋＶに変更した。その結果、１回目の帯電電位（Ｖ0）＋４０５Ｖ、半減露光量（Ｅ1/2）１．４ルックス・秒、５０００回繰り返し後の帯電電位（Ｖ0）＋４０５Ｖ、半減露光量（Ｅ1/2）１．３ルックス・秒と、高感度でしかも変化の少ない、優れた特性を示した。
【０１０１】
実施例４１〜４８
実施例４０の電荷輸送物質（例示化合物ＣＴ−３）の代わりに、それぞれ表５２に示す例示化合物を用いた他は、実施例４０と同様にして感光体を作製してその特性を評価した。結果を表５２に示す。
【０１０２】
【表５２】

【０１０３】
実施例４９〜６２
実施例４０の電荷発生物質（Ｘ型無金属フタロシアニン）及び電荷輸送物質（例示化合物ＣＴ−３）の代わりに、それぞれ表５３、表５４に示す例示化合物を用いた他は、実施例４０と同様にして感光体を作製してその特性を評価した。結果を表５３、表５４に示す。
【０１０４】
【表５３】

【０１０５】
【表５４】

【０１０６】
比較例１
電荷輸送物質としてビススチルベン化合物（例示化合物ＣＴ−３）の代わりに下記比較化合物（例示化合物ＣＴ−６７）を用いた他は、実施例１と同様に感光体を作製してその特性を評価した。その結果、１回目の帯電電位は（Ｖ0）−８００Ｖ、 半減露光量（Ｅ1/2）は１．９ルックス・秒と比較的良好な感度を示したが、５０００回目の帯電電位（Ｖ0）は−２２０Ｖ、半減露光量（Ｅ1/2）は１．０ルックス・秒であり、繰り返しによる大幅な電位の低下がみられた。
【０１０７】
【化９】

【０１０８】
比較例２
電荷輸送物質としてビススチルベン化合物（例示化合物ＣＴ−３）の代わりに、前記比較化合物（例示化合物ＣＴ−６７）を用いた他は、実施例１７と同様に感光体を作製してその特性を評価した。その結果、１回目の帯電電位（Ｖ0）は −７８０Ｖ、半減露光量（Ｅ1/2）は２．６ルックス・秒であり、感度不足であ った。
【０１０９】
比較例３
電荷輸送物質としてビススチルベン化合物（例示化合物ＣＴ−３）の代わりに下記比較化合物（ＣＴ−６８）を用いた他は、実施例４０と同様に感光体を作製してその特性を評価した。その結果、１回目の帯電電位は（Ｖ0）＋４６５Ｖ、 半減露光量（Ｅ1/2）は２．５ルックス・秒と比較的良好な感度を示したが、５ ０００回目の帯電電位（Ｖ0）は＋２３０Ｖ、半減露光量（Ｅ1/2）は２．１ルックス・秒であり、繰り返しによる大幅な電位の低下がみられた。
【０１１０】
【化１０】

【０１１１】
【発明の効果】
以上から明らかなように、本発明に係わる特定構造を有するビススチルベン化合物を利用すれば、帯電電位が高く高感度で、繰り返し使用しても諸特性が変化せず安定した性能を発揮できる電子写真感光体を提供することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic photoreceptor, and more specifically, in an electrophotographic photoreceptor having a photosensitive layer containing a charge generation material and a charge transport material as constituents on a conductive support, at least a specific bisstilbene compound is used as the charge transport material. The present invention relates to an electrophotographic photosensitive member characterized by including one kind.
[0002]
[Prior art]
In recent years, the use of electrophotography is not limited to the field of copying machines, but has spread to fields where photographic technology has been used in the past, such as printing plate materials, slide films, and microfilms, and lasers, LEDs, and CRTs are used as light sources. Applications to high-speed printers are also being studied. Therefore, the demand for electrophotographic photoreceptors is becoming high and wide. Conventionally, as an electrophotographic photoreceptor, inorganic photoconductive substances such as selenium, cadmium sulfide, zinc oxide, silicon, and the like are known, and have been extensively studied and put into practical use. These inorganic materials have many advantages and at the same time have various drawbacks. For example, selenium has the disadvantages that the production conditions are difficult and that it is easily crystallized by heat or mechanical impact, and cadmium sulfide and zinc oxide have difficulty in moisture resistance and durability. Silicon has been pointed out to be insufficiently charged and difficult to manufacture. Furthermore, selenium and cadmium sulfide have toxicity problems.
[0003]
In contrast, organic photoconductive materials have good film-forming properties, excellent flexibility, light weight, good transparency, and design of photoreceptors over a wide range of wavelengths by appropriate sensitization methods. Therefore, its practical application is gradually attracting attention.
[0004]
Incidentally, a photoreceptor used in electrophotographic technology generally requires the following as a basic property. That is, (1) High chargeability to corona discharge in dark place, (2) Little leakage (dark decay) of the obtained charged charge in dark place, (3) Charged charge by light irradiation (4) Less residual charge after light irradiation, etc.
[0005]
However, many studies have been made on photopolymer conductive materials such as polyvinyl carbazole as organic photoconductive materials to date. However, these films do not always have sufficient film properties, flexibility and adhesiveness. Also, it is difficult to say that the above-mentioned basic properties as a photoreceptor are sufficiently provided.
[0006]
On the other hand, for organic low-molecular photoconductive substances, a photoconductor excellent in mechanical strength such as film property, adhesiveness and flexibility can be obtained by selecting a binder used for forming the photoconductor. However, it is impossible to find a compound suitable for maintaining high sensitivity characteristics.
[0007]
In order to improve such a point and obtain a photoconductor having higher sensitivity characteristics, an organic photoconductor in which the charge generation function and the charge transport function are shared by different photoconductive materials has been developed. The feature of such a photoconductor, which is called a function separation type, is that a material suitable for each function can be selected from a wide range, and a photoconductor having an arbitrary performance can be easily produced. Research has progressed.
[0008]
Among these, various substances such as phthalocyanine pigments, squalium dyes, azo pigments, and perylene pigments have been studied as substances responsible for the charge generation function, and among them, azo pigments can have various molecular structures and are high. It has been widely researched because of its expectation of charge generation efficiency, and its practical application is also progressing. However, in this azo pigment, the relationship between the molecular structure and the charge generation efficiency has not yet been clarified. The reality is that we are searching for an optimal structure by accumulating a huge amount of synthetic research, but it fully satisfies the basic properties and high durability requirements for the photoreceptors listed above. Things have not been obtained yet.
[0009]
On the other hand, there are a hole transport material and an electron transport material as the materials responsible for the charge transport function. Various substances such as hydrazone compounds and styryl compounds as hole transporting substances and 2,4,7-trinitro-9-fluorenone and diphenoquinone derivatives as electron transporting substances have been studied and put into practical use. However, the fact is that we are searching for the optimal structure by accumulating a huge amount of synthetic research. In fact, many improvements have been made so far, but a product that sufficiently satisfies the basic properties, high durability, and the like required for the above-mentioned photoreceptor has not been obtained.
[0010]
As described above, various improvements have been made in the production of electrophotographic photoreceptors, but they sufficiently satisfy the basic properties and high durability requirements required for the photoreceptors listed above. Is not yet available.
[0011]
[Problems to be solved by the invention]
An object of the present invention is to provide an electrophotographic photosensitive member that has high charging potential, high sensitivity, does not change various characteristics even when used repeatedly, and can exhibit stable performance.
[0012]
[Means for Solving the Problems]
As a result of studies conducted by the present inventors to achieve the above-mentioned object, it has been found that a photoreceptor having very good sensitivity and durability can be obtained by using a bis-stilbene compound having a specific structure as a charge transport material. The headline, the present invention has been reached. The bis-stilbene compound having the above specific structure is a compound represented by the following general formula (1).
[0013]
[Chemical formula 2]

[0014]
In General Formula (1), A is an alkenyl group which may have a substituent. R ¹ and R ² represent a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group, an aryl group, or a heterocyclic group, and may have a substituent. R ³ represents an alkyl group, an aryl group, or a heterocyclic group, and may have a substituent. However, R ³ excludes a benzyl group which may have a substituent. Ar ¹ represents a methylene group or an arylene group, and may have a substituent. Ar ² represents an arylene group and may have a substituent.
[0015]
Specific examples of A include alkenyl groups such as vinyl group, allyl group, propenyl group, 2-butenyl group, 2-methylallyl group, styryl group, and cinnamyl group. Specific examples of R ¹ include a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, and a propyl group, an alkenyl group such as an allyl group, a methallyl group, and a 2-methyl-1-propenyl group, a benzyl group, and α-naphthyl. Examples include aralkyl groups such as methyl group and β-phenethylethyl group, aryl groups such as phenyl group and naphthyl group, and heterocyclic groups such as thienyl group, furyl group, pyrrolyl group, pyranyl group and pyridyl group. May have a ring-closing group. Examples of the substituent include halogen atoms such as fluorine atom, chlorine atom and bromine atom, alkoxy groups such as methoxy group, ethoxy group and propoxy group, aryloxy groups such as phenoxy group, the above alkyl groups, aryl groups and aralkyl. The group can be mentioned. Specific examples of R ² include the above-described alkyl group, aralkyl group, aryl group, and heterocyclic group, and these may have the above-described substituent. Specific examples of R ³ include the above-described alkyl group, aryl group, and heterocyclic group excluding the benzyl group , and these may have the above-described substituent.
[0016]
Specific examples of Ar ¹ include a methylene group, an o-phenylene group, and an m-phenylene group. And an arylene group such as a phenylene group such as a p-phenylene group, a naphthylene group, and a phenanthrylene group. Specific examples of Ar ² include a methylene group and the above-described arylene group.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Although the specific example of the bis stilbene compound shown by General formula (1) concerning this invention is illustrated below, it is not limited to these.
[0018]
[Chemical 3]

[0019]
[Formula 4]

[0020]
[Chemical formula 5]

[0021]
[Chemical 6]

[0022]
[Chemical 7]

[0023]
[Chemical 8]

[0024]
Although there are various types of photoreceptors, the present invention can be used in any form thereof. For example, a single-layer type photoreceptor provided with a photosensitive layer made of a photoconductive substance, a charge generating substance, a charge transporting substance, and a film-forming binder resin on a conductive support, and a charge on the conductive support. Examples thereof include a multilayer type photoreceptor provided with a charge generation layer composed of a generation material and a binder resin, and a charge transport layer composed of a charge transport material and a binder resin. Either the charge generation layer or the charge transport layer may be an upper layer. If necessary, an undercoat layer is provided between the conductive support and the photosensitive layer, an overcoat layer is provided on the surface of the photosensitive member, and in the case of a laminated type photosensitive member, an intermediate layer is provided between the charge generation layer and the charge transporting layer. Can also be provided. As a support for producing a photoreceptor using the compound according to the present invention, a metal drum, a metal plate, paper subjected to conductive processing, a sheet of plastic film, a drum or a belt, and the like are used. Is done.
[0025]
Examples of the charge generating material used in the present invention include metals such as selenium and cadmium, perylene compounds such as perylene acid anhydride and perylene imide, anthraquinone derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives, pyranthrone derivatives, violanthrone derivatives, etc. Anthraquinone pigments or polycyclic quinone pigments, phthalocyanine compounds such as metal phthalocyanine and metal-free phthalocyanine, naphthalocyanine compounds such as metal naphthalocyanine and metal-free naphthalocyanine, porphyrin pigments, quinacridone pigments, cyanine dyes, azurenium dyes, etc. Compounds are also used. Among these, those using a bisazo compound, a trisazo compound, and a phthalocyanine compound are preferable because they have high carrier generation efficiency and provide a highly sensitive photoconductor.
[0026]
Examples of the azo compound include JP-A-47-37543, JP-A-53-95033, JP-A-53-132347, JP-A-53-133445, JP-A-54-12742, and JP-A-54. -20736, JP-A-54-20737, JP-A-54-21728, JP-A-54-22834, JP-A-55-69148, JP-A-55-69654, JP-A-55-79449 JP, 55-117151, JP 56-46237, JP 56-1116039, JP 56-11640, JP 56-119134, JP 56-143437, JP-A-57-63537, JP-A-57-63538, JP-A-57-63541, JP-A-57-63542, JP-A-57-63549, JP-A-57-66438, JP 57-74746, JP 57-78542, JP 57-78543, JP 57-90056, JP 57-90057, JP 57-90632, JP 57 JP-A-116345, JP-A-57-202349, JP-A-58-4151, JP-A-58-90644, JP-A-58-144358, JP-A-58-177955, JP-A-59-31962. JP-A-59-33253, JP-A-59-71059, JP-A-59-72448, JP-A-59-78356, JP-A-59-136351, JP-A-59-201060, JP 60-15642, JP 60-14351, JP 60-179746, JP 61-11754, JP 61-90164, JP 61-90165, JP 61-90166, JP 61-112154, JP 61-281245, JP 61-51063, JP 62-267363, JP 63-68844, JP 63- 89866, JP 63-139355, JP 63-142033, JP 63-183450, JP 63-282743, JP 64-21455, JP 64-78259 JP-A-1-200267, JP-A-1-202757, JP-A-1-319754, JP-A-2-72372, JP-A-2-254467, JP-A-3-27863, JP-A-4-96068, JP-A-4-96069, JP-A-4-147265, JP-A-5-142841, JP-A-5-303226, JP-A-6-324504, JP-A-7-16 The compound described in 8379 gazette is mentioned.
[0027]
Specific examples of the azo compound include compounds shown in the following table, but are not limited thereto. It is also possible to use these compounds in combination with other charge generation materials.
[0028]
[Table 1]

[0029]
[Table 2]

[0030]
[Table 3]

[0031]
[Table 4]

[0032]
[Table 5]

[0033]
[Table 6]

[0034]
[Table 7]

[0035]
[Table 8]

[0036]
[Table 9]

[0037]
[Table 10]

[0038]
[Table 11]

[0039]
[Table 12]

[0040]
[Table 13]

[0041]
[Table 14]

[0042]
[Table 15]

[0043]
[Table 16]

[0044]
[Table 17]

[0045]
[Table 18]

[0046]
[Table 19]

[0047]
[Table 20]

[0048]
[Table 21]

[0049]
[Table 22]

[0050]
[Table 23]

[0051]
[Table 24]

[0052]
[Table 25]

[0053]
[Table 26]

[0054]
[Table 27]

[0055]
[Table 28]

[0056]
[Table 29]

[0057]
[Table 30]

[0058]
[Table 31]

[0059]
[Table 32]

[0060]
[Table 33]

[0061]
[Table 34]

[0062]
[Table 35]

[0063]
[Table 36]

[0064]
[Table 37]

[0065]
[Table 38]

[0066]
[Table 39]

[0067]
[Table 40]

[0068]
[Table 41]

[0069]
[Table 42]

[0070]
[Table 43]

[0071]
[Table 44]

[0072]
[Table 45]

[0073]
Further, for example, for phthalocyanine compounds, metal-free phthalocyanines, titanyloxyphthalocyanines, copper phthalocyanines, aluminum phthalocyanines, germanium phthalocyanines, chlorogallium phthalocyanines, chloroindium phthalocyanines, magnesium phthalocyanines, chloroaluminum phthalocyanines, Examples thereof include tin phthalocyanines, vanadyloxyphthalocyanines, gallium phthalocyanines, zinc phthalocyanines, cobalt phthalocyanines, nickel phthalocyanines, hydroxygallium phthalocyanines, dichlorotitanyl phthalocyanines, diphenoxygermanium phthalocyanines.
[0074]
As the film-forming binder resin used for forming the photosensitive layer on the support according to the present invention, various resins can be used depending on the application field. For example, in the use of photoconductors for copying, polyvinyl chloride resin, polystyrene resin, polyvinyl acetal resin, polysulfone resin, polycarbonate resin, vinyl acetate / crotonic acid copolymer resin, polyester resin, polyphenylene oxide resin, polyarylate resin, alkyd resin. , Acrylic resin, methacrylic resin, phenoxy resin and the like. Among these, polystyrene resin, polyvinyl acetal resin, polycarbonate resin, polyester resin, polyarylate resin, and the like are excellent in potential characteristics as a photoreceptor. These resins can be used alone or as a copolymer in combination of one or more. The amount of the binder resin added to the photoconductive substance is preferably 20 to 1000% by weight, and more preferably 50 to 500% by weight.
[0075]
In the case of a multilayer photoreceptor, these resins contained in the charge generation layer are preferably 10 to 500% by weight, more preferably 50 to 150% by weight, based on the charge generation material. If the resin ratio is too high, the charge generation efficiency is lowered, and if the resin ratio is too low, there is a problem in film formability. In addition, these resins contained in the charge transport layer are preferably 20 to 1000% by weight, more preferably 50 to 500% by weight with respect to the charge transport material. If the ratio of the resin is too high, the sensitivity is lowered, and if the ratio of the resin is too low, the repeated characteristics may be deteriorated or the coating film may be lost.
[0076]
Some of these resins are weak in mechanical strength such as pulling, bending, and compression. To improve this property, a plasticizing substance can be added. Specific examples include phthalic acid esters (for example, DOP and DBP), phosphoric acid esters (for example, TCP and TOP), sebacic acid esters, adipic acid esters, nitrile rubber, chlorinated hydrocarbons, and the like. When these substances are added more than necessary, the electrophotographic characteristics are adversely affected, and therefore the ratio is preferably 20% by weight or less based on the binder resin.
[0077]
In addition, a leveling agent or the like can be added as necessary to improve the coatability, such as an antioxidant or an anti-curl agent, as additives in the photoreceptor.
[0078]
The compound represented by the general formula (1) can be used in combination with another charge transporting substance. Charge transport materials include hole transport materials and electron transport materials. Examples of the former include, for example, oxadiazoles disclosed in Japanese Patent Publication No. 34-5466, triphenylmethanes disclosed in Japanese Patent Publication No. 45-555, and Japanese Patent Publication No. 52-4188. And the like, hydrazones shown in JP-B-55-42380, oxadiazoles shown in JP-A-56-123544, and the like. On the other hand, examples of the electron transport material include chloranil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4 , 5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 1,3,7-trinitrodibenzothiophene, 1,3,7-trinitrodibenzothiophene-5,5-dioxide, and the like. These charge transport materials can be used alone or in combination of two or more.
[0079]
Moreover, a certain electron withdrawing compound can also be added as a sensitizer that forms a charge transfer complex with the organic photoconductive substance according to the present invention and further enhances the sensitization effect. Examples of the electron attractive compound include quinones such as 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 1-chloro-5-nitroanthraquinone, 2-chloroanthraquinone, phenanthrenequinone, 4- Aldehydes such as nitrobenzaldehyde, ketones such as 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 3,3 ', 5,5'-tetranitrobenzophenone, phthalic anhydride, 4-chloronaphthalic anhydride Cyano compounds such as terephthalalmalononitrile, 9-anthrylmethylidenemalononitrile, 4-nitrobenzalmalononitrile, 4- (p-nitrobenzoyloxy) benzalmalononitrile, 3-benzalphthalide, 3- (α-Cyano-p-nitroben Le) phthalide, 3- (alpha-cyano -p- Nitorobenzaru) -4,5,6,7 can be mentioned phthalides such as tetrachloro phthalide like.
[0080]
The organic photoconductive substance according to the present invention is dissolved or dispersed in an appropriate solvent together with the above-mentioned various additive substances according to the form of the photoreceptor, and the coating solution is applied on the conductive support described above. The photosensitive member can be manufactured by applying to a substrate and drying.
[0081]
Coating solvents include: halogenated hydrocarbons such as chloroform, dichloroethane, dichloromethane, trichloroethane, trichloroethylene, chlorobenzene, dichlorobenzene, aromatic hydrocarbons such as benzene, toluene, xylene, dioxane, tetrahydrofuran, methyl cellosolve, ethyl cellosolve, ethylene glycol Ether solvents such as dimethyl ether, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone and cyclohexanone, ester solvents such as ethyl acetate, methyl formate and methyl cellosolve acetate, N, N-dimethylformamide, acetonitrile, N- Examples include aprotic polar solvents such as methyl pyrrolidone and dimethyl sulfoxide, and alcohol solvents. These solvents can be used alone or as a mixed solvent of two or more.
[0082]
【Example】
EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited to these at all.
[0083]
Example 1
A paint conditioner is prepared by mixing 1 part by weight of a charge generating material (Exemplary Compound K-1) and 1 part by weight of polyvinyl butyral resin (Denka Butyral # 3000-K, manufactured by Denki Kagaku Kogyo) into 100 parts by weight of 1,2-dimethoxyethane. To 4 hours with glass beads. The dispersion thus obtained was applied onto an aluminum vapor-deposited polyester with an applicator to form a charge generation layer having a thickness of about 0.4 μm. Next, 10 parts by weight of a bisstilbene compound (exemplary compound CT-3), 10 parts by weight of a polycarbonate resin (manufactured by Teijin Chemicals, Panlite C-1300), 2,5-di-t-butylhydroquinone (hereinafter abbreviated as TBH) 0 .2 parts by weight was dissolved in 150 parts by weight of dichloromethane and applied on the charge generation layer with an applicator to form a charge transport layer having a thickness of about 20 μm.
[0084]
The laminated photoreceptor thus prepared was stored overnight in the dark at room temperature, and then electrophotographic characteristic evaluation was performed using an electrostatic recording test apparatus (manufactured by Kawaguchi Electric Co., Ltd., SP-428).
Measurement conditions: applied voltage -6 kV, static No. 3 (turntable rotation speed mode: 10 m / min), irradiation light illuminance 2 lux.
As a result, the charging potential V0 was -835V, and the half exposure amount E1 / 2 was 0.88 lux.sec.
[0085]
Next, this photoconductor was attached to an aluminum drum base tube, and the repetition characteristics of charging and photostatic removal were evaluated by a drum photoconductor evaluation device (Gentec, Cynthia 90).
Measurement conditions: Corona applied voltage -5.2 kV, process speed 160 mm / s, TCCD mode 2, photostatic discharge: tungsten lamp array.
As for the surface potential after charging (charging potential V0) and the surface potential after photostatic elimination (residual potential Vr), the first charging potential V0 is −843 V, the residual potential Vr is −47 V, and the 5000th charging potential V0 is − The residual potential Vr was 856 V and -46 V, and it was found that the change due to repetition was extremely small.
[0086]
Example 2-9
A photoconductor was prepared in the same manner as in Example 1 except that the compounds shown in Table 46 were used instead of the bisstilbene compound (Exemplary Compound CT-3) of Example 1, and the characteristics thereof were evaluated. Table 46 shows the half-exposure dose E1 / 2, the difference between the first and 5000th charging potentials (ΔV0), and the difference between the residual potentials (ΔVr).
[0087]
[Table 46]

[0088]
Examples 10-16
A photoconductor in the same manner as in Example 1 except that the example compounds shown in Table 47 were used instead of the charge generation material (Example Compound K-1) and the charge transport material (Example Compound CT-3) of Example 1. Were fabricated and their characteristics were evaluated. The results are shown in Table 47.
[0089]
[Table 47]

[0090]
Example 17
1 part by weight of X-type metal-free phthalocyanine and 1 part by weight of a polyester resin (Toyobo, Byron 220) were mixed with 100 parts by weight of dioxane, and dispersed with glass beads in a paint conditioner device for 3 hours. The dispersion thus obtained was applied onto an aluminum vapor-deposited polyester with an applicator and dried to form a charge generation layer having a thickness of about 0.2 μm. Next, the bis-stilbene compound (Exemplary Compound CT-3) is mixed with polyarylate resin (manufactured by Unitika, U-polymer) at a weight ratio of 1: 1 to make a 10% by weight solution using dichloroethane as a solvent. A charge transport layer having a thickness of about 20 μm was formed on the charge generation layer with an applicator.
[0091]
The laminated photoconductors thus produced were evaluated for electrophotographic characteristics using an electrostatic recording test apparatus (SP-428 manufactured by Kawaguchi Electric).
Measurement conditions: applied voltage -6 kV, static No. 3 (turn table rotation speed mode: 10 m / min). As a result, the charging potential (V0) was -776 V, and the half exposure amount (E1 / 2) was 1.1 lux.sec.
[0092]
Further, using the same apparatus, the characteristics were evaluated for repeated use with one cycle of charge-static elimination (static elimination light: 400 lux × 1 second irradiation with white light). When the change in the charging potential by repeating 5000 times was obtained, the charging potential (V0) at 5000 times was -790 V with respect to the first charging potential (V0) -795 V, and the potential decrease due to repetition was stable and stable. Showed the characteristics. In addition, the first half-exposure (E1 / 2) is 1.1 lux · second, and the 5000th half-exposure (E1 / 2) is 1.1 lux · second. It was.
[0093]
Examples 18-25
Instead of the charge transport material of Example 17 (Compound CT-3), the other with respective exemplary compounds shown in Table 48, and its characteristics were evaluated by producing a photoreceptor in the same manner as in Example 17. The results are shown in Table 48.
[0094]
[Table 48]

[0095]
Table 49 shows the peak positions in the X-ray diffraction spectra of phthalocyanines used in the following Examples and Comparative Examples, and the abbreviations used in the table.
[0096]
[Table 49]

[0097]
Examples 26-39
Instead of the charge generation material (X-type metal-free phthalocyanine), and the charge transport material of Example 17 (Compound CT-3), the other with each table 50, exemplary compounds shown in Table 51, as in Example 17 Thus, a photoconductor was prepared and its characteristics were evaluated. The results are shown in Table 50 and Table 51.
[0098]
[Table 50]

[0099]
[Table 51]

[0100]
Example 40
One part by weight of X-type metal-free phthalocyanine and 40 parts by weight of tetrahydrofuran were dispersed with a glass bead for 4 hours using a paint conditioner device. To the dispersion thus obtained, 2.5 parts by weight of a bisstilbene compound (exemplary compound CT-3), 10 parts by weight of a polycarbonate resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., PCZ-200) and 60 parts by weight of tetrahydrofuran are added, and further a paint conditioner. After carrying out a dispersion treatment for 30 minutes with an apparatus, it was applied onto an aluminum vapor-deposited polyester with an applicator to form a photoreceptor having a film thickness of about 15 μm. The electrophotographic characteristics of this photoreceptor were evaluated in the same manner as in Example 1. However, only the applied voltage was changed to +5 kV. As a result, the first charging potential (V 0) +405 V, half-exposure amount (E 1/2) 1.4 lux · second, charging potential (V 0) +405 V after 5,000 repetitions, half-exposure amount (E 1/2) Excellent characteristics with high sensitivity and little change of 3 lux / second.
[0101]
Examples 41-48
Instead of the charge transport material of Example 40 (Compound CT-3), the other with respective exemplary compounds shown in Table 52, and its characteristics were evaluated by producing a photoreceptor in the same manner as in Example 40. The results are shown in Table 52.
[0102]
[Table 52]

[0103]
Examples 49-62
The same procedure as in Example 40 except that the example compounds shown in Table 53 and Table 54 were used instead of the charge generation material (type X metal-free phthalocyanine) and the charge transport material (example compound CT-3) in Example 40 , respectively. Thus, a photoconductor was prepared and its characteristics were evaluated. The results are shown in Table 53 and Table 54.
[0104]
[Table 53]

[0105]
[Table 54]

[0106]
Comparative Example 1
A photoconductor was prepared and evaluated for its characteristics in the same manner as in Example 1 except that the following comparative compound (Exemplary Compound CT-67) was used instead of the bistilbene compound (Exemplary Compound CT-3) as the charge transport material. . As a result, the first charging potential was (V0) -800V, and the half-exposure amount (E1 / 2) was 1.9 lux · second, indicating a relatively good sensitivity, but the 5000th charging potential (V0) was The -220 V, half-exposure dose (E1 / 2) was 1.0 lux.sec., And a significant decrease in potential due to repetition was observed.
[0107]
[Chemical 9]

[0108]
Comparative Example 2
A photoconductor was prepared in the same manner as in Example 17 except that the comparative compound (Exemplary Compound CT-67) was used in place of the bistilbene compound (Exemplary Compound CT-3) as a charge transport material, and its characteristics were evaluated. did. As a result, the first charging potential (V 0) was −780 V, the half exposure amount (E 1/2) was 2.6 lux · second, and the sensitivity was insufficient.
[0109]
Comparative Example 3
A photoconductor was prepared and evaluated for its characteristics in the same manner as in Example 40 except that the following comparative compound (CT-68) was used as the charge transport material instead of the bisstilbene compound (Exemplary Compound CT-3). As a result, the first charging potential was (V0) + 465V, and the half-exposure amount (E1 / 2) was 2.5 lux.sec. +230 V, half-exposure amount (E1 / 2) was 2.1 lux · second, and a significant decrease in potential due to repetition was observed.
[0110]
[Chemical Formula 10]

[0111]
【The invention's effect】
As can be seen from the above, by using the bisstilbene compound having a specific structure according to the present invention, an electrophotography that exhibits a stable performance without changing various characteristics even when used repeatedly with high charge potential and high sensitivity. A photoreceptor can be provided.

Claims (1)

In an electrophotographic photosensitive member having a photosensitive layer containing a charge generating material and a charge transporting material as constituents on a conductive support, at least one bisstilbene compound represented by the following general formula (1) is included as a charge transporting material. An electrophotographic photosensitive member.

(In General Formula (1), A represents an alkenyl group which may have a substituent. R ¹ and R ² represent a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group, an aryl group, or a heterocyclic group. R ³ represents an alkyl group, an aryl group, or a heterocyclic group, and may have a substituent, provided that R ³ has a substituent . Ar ¹ represents a methylene group or an arylene group, and may have a substituent, Ar ² represents an arylene group, and may have a substituent.