JP4162808B2 - Organic photoconductive compound and electrophotographic photoreceptor using the same - Google Patents

Description

【００１４】
【化４】

【００１５】
本発明の一般式（１）或いは（２）において、Ｒ₁及びＲ₂は水素原子、置換基を有していてもよいアルキル基、アラルキル基、アリール基、または複素環を示し、Ａｒは置換基を有していてもよいアリール基または複素環基を示す。
【００１６】
ここで、Ｒ₁及びＲ₂の具体例としては、水素原子、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、ｎ−ヘキシル基、２−メトキシエチル基などのアルキル基、ベンジル基、４−メチルベンジル基、３−メトキシベンジル基、２−（４−クロロフェニル）エチル基、などのアラルキル基、フェニル基、４−メチルフェニル基、２メトキシフェニル基、４−クロロフェニル基、３−ジエチルアミノフェニル基、１−ナフチル基、１−ピレニル基、などのアリール基、または、２−フリル基、３−チエニル基、２−ピリジル基、２−インドリル基、４−カルバゾリル基、２−ピペリジル基などの複素環基を挙げることができる。
【００１７】
また、Ａｒの具体例としては、フェニル基、４−メチルフェニル基、２メトキシフェニル基、４−クロロフェニル基、３−ジエチルアミノフェニル基、１−ナフチル基、１−ピレニル基、などのアリール基、２−フリル基、３−チエニル基、２−ピリジル基、２−インドリル基、４−カルバゾリル基、２−ピペリジル基などの複素環基を挙げることができる。
【００１８】
【発明の実施の形態】
本発明の一般式（１）または（２）で示される有機光導電性化合物の具体例としては、以下に示すＥ−０１〜２０のビスエナミン系化合物を挙げることができるが、これらに限定されるものではない。
【００１９】
【化５】

【００２０】
【化６】

【００２１】
【化７】

【００２２】
【化８】

【００２３】
本発明におけるビスエナミン系化合物は、下記の合成経路により容易に合成される。
【００２４】
すなわち、下記一般式（３）で示されるエナミン〜アルデヒド化合物と、（３）に対し０．５モル当量の、下記一般式（４）で表されるビスホスフォネート化合物を、Ｎ，Ｎ−ジメチルホルムアミドやＮ，Ｎ−ジメチルアセトアミド等のアミド系溶媒、ジオキサンやジオキソラン等の環状エーテル系溶媒、あるいはエタノールやプロパノール等のアルコール系溶媒等を用い、（３）に対し１．０モル当量〜１．５モル当量のカリウムｔ−ブトキシドやナトリウムメトキシド等の塩基を加え、室温下あるいは５０〜１００℃加温下、０．５〜８時間程度反応させる事により、容易に合成出来る。
【００２５】
【化９】

【００２６】
【化１０】

【００２７】
上記一般式（３）におけるＲ₁，Ｒ₂，及びＡｒは、一般式（１）で示されるビスエナミン系化合物と同じであり、また、上記一般式（４）のＲ₃は、メチル基、エチル基等の低級アルキル基を表している。
【００２８】
上記反応の合成原料となる一般式（３）のエナミン〜アルデヒド化合物は、Ｒ₁，Ｒ₂が共にアリール基の場合には、特開平１１−４３４５８号公報に記載の方法で、またそれ以外の場合には、Ｏｒｇａｎｉｃ Ｓｙｎｔｈｅｓｅｓ Ｃｏｌｌ．Ｖｏｌ．III，７２７−７２８ページ、及び同７３３−７３４ページに記載の方法を用いて得られるアセトアルデヒド誘導体を、ｐ−トルエンスルホン酸等の酸触媒の存在下、ジアミン化合物と縮合させてエナミン化合物とし、これを更にヴィルスマイヤー反応等によりホルミル化する事により得られる。
【００２９】
また、一方の合成原料である一般式（４）のビスホスフォネート化合物については、１，４−ジクロロ−２−ブテンを、下記一般式（５）の亜リン酸トリアルキルとともに加熱して反応させ、蒸留精製する事により容易に得られる。
【００３０】
【化１１】

【００３１】
上記一般式（５）におけるＲ₃は、一般式（４）のＲ₃と同じである。
【００３２】
本発明の、一般式（１）または（２）で示される有機光導電性化合物を含有する感光層を含む電子写真感光体の形態は、そのいずれを用いることもできる。例えば、導電性支持体上に電荷発生物質、電荷輸送物質、及びフィルム形成性結着剤樹脂からなる感光層を設けたものがある。また、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も知られている。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。本発明の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や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などが使用される。
【００３３】
本発明の電子写真感光体は、一般式（１）または（２）で示される有機光導電性化合物、及び電荷発生物質をそれぞれ１種類あるいは２種類以上含有することにより得られる。電荷発生物質には無機系電荷発生物質と有機系電荷発生物質があり、前者の例としては例えばセレン、セレン−テルル合金、セレン−ヒ素合金、硫化カドミウム、酸化亜鉛、アモルファスシリコンなどが挙げられる。有機系電荷発生物質の例としては、例えばメチルバイオレット、ブリリアントグリーン、クリスタルバイオレットなどのトリフェニルメタン系染料、メチレンブルーなどのチアジン染料、キニザリンなどのキノン染料、シアニン染料、アクリジン染料、ピリリウム色素、チアピリリウム色素、スクエアリウム色素、ペリノン系顔料、アントラキノン系顔料、ペリレン系顔料、金属含有あるいは無金属のフタロシアニン系顔料などが挙げられ、また、アゾ顔料も用いられる。
【００３４】
アゾ顔料としては、例えば特開昭４７−３７５４３号公報、特開昭５３−９５０３３号公報、特開昭５３−１３２３４７号公報、特開昭５３−１３３４４５号公報、特開昭５４−１２７４２号公報、特開昭５４−２０７３６号公報、特開昭５４−２０７３７号公報、特開昭５４−２１７２８号公報、特開昭５４−２２８３４号公報、特開昭５５−６９１４８号公報、特開昭５５−６９６５４号公報、特開昭５５−７９４４９号公報、特開昭５５−１１７１５１号公報、特開昭５６−４６２３７号公報、特開昭５６−１１６０３９号公報、特開昭５６−１１６０４０号公報、特開昭５６−１１９１３４号公報、特開昭５６−１４３４３７号公報、特開昭５７−６３５３７号公報、特開昭５７−６３５３８号公報、特開昭５７−６３５４１号公報、特開昭５７−６３５４２号公報、特開昭５７−６３５４９号公報、特開昭５７−６６４３８号公報、特開昭５７−７４７４６号公報、特開昭５７−７８５４２号公報、特開昭５７−７８５４３号公報、特開昭５７−９００５６号公報、特開昭５７−９００５７号公報、特開昭５７−９０６３２号公報、特開昭５７−１１６３４５号公報、特開昭５７−２０２３４９号公報、特開昭５８−４１５１号公報、特開昭５８−９０６４４号公報、特開昭５８−１４４３５８号公報、特開昭５８−１７７９５５号公報、特開昭５９−３１９６２号公報、特開昭５９−３３２５３号公報、特開昭５９−７１０５９号公報、特開昭５９−７２４４８号公報、特開昭５９−７８３５６号公報、特開昭５９−１３６３５１号公報、特開昭５９−２０１０６０号公報、特開昭６０−１５６４２号公報、特開昭６０−１４０３５１号公報、特開昭６０−１７９７４６号公報、特開昭６１−１１７５４号公報、特開昭６１−９０１６４号公報、特開昭６１−９０１６５号公報、特開昭６１−９０１６６号公報、特開昭６１−１１２１５４号公報、特開昭６１−２６９１６５号公報、特開昭６１−２８１２４５号公報、特開昭６１−５１０６３号公報、特開昭６２−２６７３６３号公報、特開昭６３−６８８４４号公報、特開昭６３−８９８６６号公報、特開昭６３−１３９３５５号公報、特開昭６３−１４２０６３号公報、特開昭６３−１８３４５０号公報、特開昭６３−２８２７４３号公報、特開昭６４−２１４５５号公報、特開昭６４−７８２５９号公報、特開平１−２００２６７号公報、特開平１−２０２７５７号公報、特開平１−３１９７５４号公報、特開平２−７２３７２号公報、特開平２−２５４４６７号公報、特開平３−９５５６１号公報、特開平３−２７８０６３号公報、特開平４−９６０６８号公報、特開平４−９６０６９号公報、特開平４−１４７２６５号公報、特開平５−１４２８４１号公報、特開平５−３０３２２６号公報、特開平６−３２４５０４号公報、特開平７−１６８３７９号公報などに記載の化合物が挙げられる。
【００３５】
また、これらのアゾ顔料に用いられるカプラー成分の構造は多岐に渡る。例えば特開昭５４−１７７３５号公報、特開昭５４−７９６３２号公報、特開昭５７−１７６０５５号公報、特開昭５９−１９７０４３号公報、特開昭６０−１３０７４６号公報、特開昭６０−１５３０５０号公報、特開昭６０−１０３０４８号公報、特開昭６０−１８９７５９号公報、特開昭６３−１３１１４６号公報、特開昭６３−１５５０５２号公報、特開平２−１１０５６９号公報、特開平４−１４９４４８号公報、特開平６−２７７０５号公報、特開平６−３４８０４７号公報などに記載の化合物が挙げられる。
【００３６】
上記アゾ顔料の具体例としては、以下の表１〜４５に示す化合物を挙げることができるが、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。
【００３７】
【表１】

【００３８】
【表２】

【００３９】
【表３】

【００４０】
【表４】

【００４１】
【表５】

【００４２】
【表６】

【００４３】
【表７】

【００４４】
【表８】

【００４５】
【表９】

【００４６】
【表１０】

【００４７】
【表１１】

【００４８】
【表１２】

【００４９】
【表１３】

【００５０】
【表１４】

【００５１】
【表１５】

【００５２】
【表１６】

【００５３】
【表１７】

【００５４】
【表１８】

【００５５】
【表１９】

【００５６】
【表２０】

【００５７】
【表２１】

【００５８】
【表２２】

【００５９】
【表２３】

【００６０】
【表２４】

【００６１】
【表２５】

【００６２】
【表２６】

【００６３】
【表２７】

【００６４】
【表２８】

【００６５】
【表２９】

【００６６】
【表３０】

【００６７】
【表３１】

【００６８】
【表３２】

【００６９】
【表３３】

【００７０】
【表３４】

【００７１】
【表３５】

【００７２】
【表３６】

【００７３】
【表３７】

【００７４】
【表３８】

【００７５】
【表３９】

【００７６】
【表４０】

【００７７】
【表４１】

【００７８】
【表４２】

【００７９】
【表４３】

【００８０】
【表４４】

【００８１】
【表４５】

【００８２】
本発明において使用するフタロシアニン系顔料としては、それ自体公知のフタロシアニン及びその誘導体のいずれでも使用でき、具体的には、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、ジフェノキシゲルマ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、ガリ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、ブロモ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、ブロモインジウムフタロシアニン類、ヨード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、ブロモアルミニウムフタロシアニン類、スズフタロシアニン類、ジクロロ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、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、ジヒドロキシガリウムフタロシアニン類、バリウムフタロシアニン類、ベリリウムフタロシアニン類、カドミウムフタロシアニン類、クロロコバルトフタロシアニン類、ジクロロチタニルフタロシアニン類、鉄フタロシアニン類、シリコンフタロシアニン類、鉛フタロシアニン類、白金フタロシアニン類、無金属ナフタロシアニン類、アルミニウムナフタロシアニン類、チタニルオキシナフタロシアニン類、ルテニウムフタロシアニン、パラジウムフタロシアニンなどが挙げられる。特にその中でも無金属フタロシアニン、チタニルオキシフタロシアニン、銅フタロシアニン、クロロアルミニウムフタロシアニン、クロロインジウムフタロシアニン、バナジルオキシフタロシアニン、ジフェノキシゲルマニウムフタロシアニン、クロロガリウムフタロシアニン、ヒドロキシガリウムフタロシアニンが本発明では好ましく用いられる。
【００８３】
また、フタロシアニン系顔料は結晶多型の化合物として知られ、各種結晶型のフタロシアニン系顔料が見出されている。これらの結晶型や製造方法に関する記述として、無金属フタロシアニンは、特公昭４９−４３３８号公報、特開昭５８−１８２６３９号公報、特開昭６０−１９１５１号公報、特開昭６２−４７０５４号公報、特開昭６２−１４３０５８号公報、特開昭６３−２８６８５７号公報、特開平１−１３８５６３号公報、特開平１−２３０５８１号公報、特開平２−２３３７６９号公報、更にはＪ．Ｐｈｙｓ．Ｃｈｅｍ．７２，３２３０（１９６８）に記載されているものを挙げることができる。
【００８４】
チタニルオキシフタロシアニンは、特開昭６１−２１７０５０号公報、特開昭６２−６７０９４号公報、特開昭６２−２２９２５３号公報、特開昭６３−３６４号公報、特開昭６３−３６５号公報、特開昭６３−３６６号公報、特開昭６３−３７１６３号公報、特開昭６３−８０２６３号公報、特開昭６３−１１６１５８号公報、特開昭６３−１９８０６７号公報、特開昭６３−２１８７６８号公報、特開昭６４−１７０６６号公報、特開平１−１２３８６８号公報、特開平１−１３８５６２号公報、特開平１−１５３７５７号公報、特開平１−１７２４５９号公報、特開平１−１７２４６２号公報、特開平１−１８９２００号公報、特開平１−２０４９６９号公報、特開平１−２０７７５５号公報、特開平１−２９９８７４号公報、特開平２−８２５６号公報、特開平２−９９９６９号公報、特開平２−１３１２４３号公報、特開平２−１６５１５６号公報、特開平２−１６５１５７号公報、特開平２−２１５８６６号公報、特開平２−２６７５６３号公報、特開平２−２９７５６０号公報、特開平３−３５０６４号公報、特開平３−５４２６４号公報、特開平３−８４０６８号公報、特開平３−９４２６４号公報、特開平３−１００６５８号公報、特開平３−１００６５９号公報、特開平３−１２３３５９号公報、特開平３−１９９２６８号公報、特開平３−２００７９０号公報、特開平３−２６９０６４号公報、特開平４−１４５１６６号公報、特開平４−１４５１６７号公報、特開平４−１５３２７３号公報、特開平４−１５９３７３号公報、特開平４−１７９９６４号公報、特開平５−２０２３０９号公報、特開平５−２７９５９２号公報、特開平５−２８９３８０号公報、特開平６−３３６５５４号公報、特開平７−８２５０３号公報、特開平７−８２５０５号公報、更には特開平８−１１０６４９号公報に記載されているものを挙げることができる。
【００８５】
また、銅フタロシアニンは、特公昭５２−１６６７号公報、特開昭５１−１０８８４７号公報、特開昭５５−６０９５８号公報に記載されているものや、更にはγ型、π型、χ型、ρ型などが知られておりこれらを挙げることができる。クロロアルミニウムフタロシアニンは、特開昭５８−１５８６４９号公報、特開昭６２−１３３４６２号公報、特開昭６２−１６３０６０号公報、特開昭６３−４３１５５号公報、更には特開昭６４−７０７６２号公報に、クロロインジウムフタロシアニンは特開昭５９−４４０５４号公報、特開昭６０−５９３５５号公報、特開昭６１−４５２４９号公報、更には特開平７−１３３７５号公報に、バナジルオキシフタロシアニンは、特開昭６３−１８３６１号公報、特開平１−２０４９６８号公報、特開平１−２６８７６３号公報、特開平３−２６９０６３号公報、更には特開平７−２４７４４２号公報に、ジフェノキシゲルマニウムフタロシアニンは、特開平４−３６０１５０号公報に、クロロガリウムフタロシアニンは、特開平５−１９４５２３号公報、更には特開平７−１０２１８３号公報に、ヒドロキシガリウムフタロシアニンは、特開平５−２６３００７号公報、更には特開平７−５３８９２号公報に記載されているものを挙げることができる。
【００８６】
本発明の一般式（１）または（２）で示される有機光導性化合物を含む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、フェノキシ樹脂あるいはポリ塩化ビニル樹脂などが挙げられる。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などは感光体としての電位特性に優れている。また、これらの樹脂は、単独あるいは共重合体のいずれでもよく、またこれらの１種または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化合物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。
【００８７】
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。
【００８８】
これらの樹脂の中には、引っ張り、曲げ、圧縮など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など）、リン酸エステル（例えばＴＣＰ、ＴＯＰなど）、セバシン酸エステル、アジピン酸エステル、ニトリルゴム、塩素化炭化水素などが挙げられる。これらの物質は、必要以上に添加すると電子写真特性に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。
【００８９】
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など、塗工性の改良のためレベリング剤などを必要に応じて添加することができる。
【００９０】
一般式（１）または（２）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号公報などに示されているオキサジアゾール類、特公昭４５−５５５号公報などに示されているトリフェニルメタン類、特公昭５２−４１８８号公報などに示されているピラゾリン類、特公昭５５−４２３８０号公報などに示されているヒドラゾン類、特開昭５６−１２３５４４号公報などに示されているオキサジアゾール類など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−ジオキシドなどがある。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。
【００９１】
また、一般式（１）または（２）で示される化合物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などのキノン類、４−ニトロベンズアルデヒドなどのアルデヒド類、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などのケトン類、無水フタル酸、４−クロロナフタル酸無水物などの酸無水物、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などのシアノ化合物、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などのフタリド類などを挙げることができる。
【００９２】
本発明の有機光導電性化合物は、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または分散し、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。
【００９３】
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、ジクロロベンゼンなどのハロゲン化炭化水素、ベンゼン、トルエン、キシレンなどの芳香族炭化水素、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などのエーテル系溶剤、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、シクロヘキサノンなどのケトン系溶剤、酢酸エチル、ギ酸メチル、メチルセロソルブアセテートなどのエステル系溶剤、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などの非プロトン性極性溶剤及びｎ−ブタノール、２−プロパノールなどのアルコール系溶剤など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。
【００９４】
【実施例】
次に本発明を実施例により更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。
【００９５】
【化１２】

【００９６】
【化１３】

【００９７】
合成例１ 例示化合物（Ｅ−１４）の合成
１ａ）エナミン〜アルデヒド化合物（上記（６））の合成
Ｎ，Ｎ−ジメチルホルムアミド２７ｍｌを氷冷下撹拌している中にオキシ塩化リン１７．２ｍｌをゆっくり滴下し、ヴィルスマイヤー試薬を調製する。上記のヴィルスマイヤー試薬を氷冷下撹拌している中に、上記（７）のエナミン化合物〔合成法は特開平１１−４３４５８号に記載有り〕１２．０ｇをＮ，Ｎ−ジメチルホルムアミド２４０ｍｌに溶かした溶液を滴下し、室温下で１５分撹拌した後、９０℃で４時間攪拌する。反応液を氷水２００ｍｌにあけて、２規定水酸化ナトリウム水溶液で中和したのち、析出結晶を濾取し、水洗、メタノール洗浄の後、アセトニトリルで再結晶して（６）９．０９ｇを得た。収率は７０．２％、融点は１４９〜１５０℃であった。
【００９８】
１ｂ）ビスフォスフォネート化合物（下記（８））の合成
１，４−ジクロロ−２−ブテン１４ｇ、及び亜リン酸トリエチル４０ｇを撹拌しながら１４０℃に加熱し、６時間反応させたのち、減圧下亜リン酸トリエチルを除去して、オイル状の（８）２７．３４ｇを得た。収率は７４．４％であった。
【００９９】
【化１４】

【０１００】
１ｃ）例示化合物（Ｅ−１４）の合成
（６）８．３ｇ及び（８）３．２９ｇを溶かしたＮ，Ｎ−ジメチルホルムアミド５０ｍｌ溶液に、室温で撹拌下、カリウムｔ−ブトキシド３．７２ｇをゆっくりと加えた。室温下一昼夜撹拌を続けた後、反応液を氷水２５０ｍｌに注ぎ込んで反応を停止し、室温下しばらく撹拌した後、生成している褐色結晶をクロロホルムで抽出した。有機層を分離し、無水硫酸マグネシウムで乾燥し、減圧下溶媒を留去した。得られたオイル状物質をシリカゲルカラムクロマトグラフィー（溶出溶媒：トルエン）で精製して目的とする化合物（Ｅ−１４）２．６１ｇを得た。収率は３３．９％、融点は７９〜８４℃であった。
【０１０１】
このものは、¹Ｈ−ＮＭＲ（δ，ｐｐｍ，ＣＤＣｌ₃）において、７．４〜６．８（ｍ，２８Ｈ）、６．７１（ｔ，８Ｈ）、６．４７（ｄ，４Ｈ）、６．４１（ｄ，４Ｈ）、６．１４（ｄ，２Ｈ）のピークを示している事から、その構造が確認された。
【０１０２】
実施例１
アゾ顔料（Ｋ−２）１重量部及びポリエステル樹脂（東洋紡製バイロン２００）１重量部をテトラヒドロフラン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２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。次に本発明の例示化合物（Ｅ−１４）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。
【０１０３】
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ＥＰＡ−８２００）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−７２０Ｖ、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。
【０１０４】
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）−７２０Ｖに対し、５０００回目の帯電電位（Ｖ₀）は−７１０Ｖであり、繰返しによる電位の低下がほとんど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。
【０１０５】
実施例２〜１１
実施例１のアゾ顔料（Ｋ−２）及び本発明の例示化合物（Ｅ−１４）の代わりに、それぞれ表４６に示すアゾ顔料、及び本発明の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４６に示す。
【０１０６】
【表４６】

【０１０７】
実施例１２
アゾ顔料（Ｈ−１）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８時間分散処理した。こうして得た分散液に、本発明の例示化合物（Ｅ−１４）を２．５重量部、ポリカーボネート樹脂（三菱瓦斯化学製ＰＣＺ−２００）１０重量部、テトラヒドロフラン６０重量部を加え、更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の感光層を形成した。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）＋４５０Ｖ、半減露光量（Ｅ1/2）１．３ルックス・秒に対し、５０００回繰り返し後の帯電電位（Ｖ₀）＋４４０Ｖ、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。
【０１０８】
実施例１３〜２２
実施例１２のアゾ顔料（Ｈ−１）及び本発明の例示化合物（Ｅ−１４）の代わりに、それぞれ表４７に示すアゾ顔料及び本発明の例示化合物を用いた他は、実施例１２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。
【０１０９】
【表４７】

【０１１０】
実施例２３〜２７
実施例１のアゾ顔料（Ｋ−２）の代わりにＣｕＫα１．５４１オングストロームのＸ線に対するブラッグ角（２θ±０．２°）が、９．５°、９．７°、１１．７°、１５．０°、２３．５°、２４．１°、２７．３°に主要なピークを示すＸ線回折スペクトルを有するチタニルオキシフタロシアニン（Ｙ型チタニルオキシフタロシアニン）を、また電荷輸送物質として表４８に示す本発明の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４８に示す。
【０１１１】
【表４８】

【０１１２】
実施例２８〜３２
実施例１２のアゾ顔料（Ｈ−１）の代わりにＹ型チタニルオキシフタロシアニンを、また電荷輸送物質として表４９に示す本発明の例示化合物を用いた他は、実施例１２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４９に示す。
【０１１３】
【表４９】

【０１１４】
比較例１
電荷輸送物質として本発明の例示化合物（Ｅ−１４）の代わりに下記に示す比較化合物（Ｒ−１）を用いた他は、実施例１と同様の操作で感光体を作製し特性を評価した結果、１回目の帯電電位（Ｖ₀）−６６０Ｖに対し、５０００回目の帯電電位（Ｖ₀）は−４１０Ｖであり、初期の帯電電位が悪い上に、繰返しによる大幅な電位の低下がみられた。また、１回目の半減露光量（Ｅ1/2）２．７ルックス・秒に対して５０００回目の半減露光量（Ｅ1/2）は４．７ルックス・秒と感度の低下もみられた。
【０１１５】
【化１５】

【０１１６】
比較例２
同様にして、電荷輸送物質として本発明の例示化合物（Ｅ−１４）の代わりに下記に示す比較化合物（Ｒ−２〜４）を用いた他は、実施例１と同様の操作で感光体を作製し特性を評価した。結果は表５０に示したように、全てのもので感度の低下や、繰り返しによる帯電電位の低下がみられた。
【０１１７】
【化１６】

【０１１８】
【化１７】

【０１１９】
【化１８】

【０１２０】
【表５０】

【０１２１】
【発明の効果】
以上から明らかなように、本発明の有機光導電性化合物を用いれば高感度で高耐久性を有する、優れた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 a novel organic photoconductive compound and an electrophotographic photoreceptor using the same.
[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 considered. Recently, application of photoconductive materials to applications other than electrophotographic photoreceptors, such as electrostatic recording elements, sensor materials, EL elements, etc., has begun to be studied. Accordingly, the demand for photoconductive materials and electrophotographic photoreceptors using the same is becoming high and wide. To date, inorganic photoconductive substances such as selenium, cadmium sulfide, zinc oxide, and silicon are known as electrophotographic photoreceptors, and have been widely 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]
By the way, 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) Residual charge after light irradiation is small.
[0005]
To date, many studies have been made on photoconductive polymers such as polyvinyl carbazole as organic photoconductive materials. However, these films do not necessarily have sufficient film properties, flexibility, and adhesive properties, and the above-described photosensitivity. It is difficult to say that the body has sufficient basic properties.
[0006]
On the other hand, for organic low-molecular photoconductive compounds, 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, there is a drawback that it is difficult to find a compound suitable for maintaining high sensitivity characteristics.
[0007]
In order to improve such a point, an organic photoreceptor having higher sensitivity characteristics in which the charge generation function and the charge transport function are assigned to different substances has been developed. The feature of such photoconductors, which are called function-separated types, 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. Has been promoted.
[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. Among them, azo pigments can have various molecular structures, and are also 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 is still unclear. The reality is that we are exploring optimal structures by accumulating vast amounts of synthetic research, and so far we have been demanding basic properties and high durability required for the photoreceptors listed above. We have not yet obtained a satisfactory content.
[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 materials such as hydrazone compounds and stilbene compounds as hole transport materials and 2,4,7-trinitro-9-fluorenone and diphenoquinone derivatives as electron transport materials have been studied and are in practical use. 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 and high durability required for the photosensitive member described above has not been obtained.
[0010]
As described above, various improvements have been made in the production of electrophotographic photosensitive members, but they sufficiently satisfy the basic properties and high durability required for the photosensitive members listed above. Is not yet available.
[0011]
[Problems to be solved by the invention]
The object of the present invention is that when used as a material for an electrophotographic photosensitive member, the charging potential is high, the sensitivity is high, the characteristics do not change even after repeated use, and stable performance can be exhibited. Another object of the present invention is to provide a novel organic photoconductive compound that can be used in electrostatic recording elements and the like.
[0012]
[Means for Solving the Problems]
As a result of researches on organic photoconductive compounds in order to achieve the above object, the present inventors have found that organic photoconductive compounds having a specific structure are effective, leading to the present invention. Examples of the organic photoconductive compound having a specific structure described above include a bisenamine compound represented by the following general formula (1). Among them, a bisenamine compound represented by the following general formula (2) is preferable in the present invention. Compounds.
[0013]
[Chemical 3]

[0014]
[Formula 4]

[0015]
In the general formula (1) or (2) of the present invention, R ₁ And R ₂ Represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group, an aryl group or a heterocyclic ring, and Ar represents an aryl group or a heterocyclic group which may have a substituent.
[0016]
Where R ₁ And R ₂ Specific examples of these include hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, n-hexyl group, alkyl group such as 2-methoxyethyl group, benzyl group, 4-methylbenzyl. Groups, aralkyl groups such as 3-methoxybenzyl group, 2- (4-chlorophenyl) ethyl group, phenyl group, 4-methylphenyl group, 2methoxyphenyl group, 4-chlorophenyl group, 3-diethylaminophenyl group, 1- An aryl group such as naphthyl group and 1-pyrenyl group, or a heterocyclic group such as 2-furyl group, 3-thienyl group, 2-pyridyl group, 2-indolyl group, 4-carbazolyl group and 2-piperidyl group Can be mentioned.
[0017]
Specific examples of Ar include aryl groups such as phenyl group, 4-methylphenyl group, 2 methoxyphenyl group, 4-chlorophenyl group, 3-diethylaminophenyl group, 1-naphthyl group, 1-pyrenyl group, and the like. Examples include heterocyclic groups such as -furyl group, 3-thienyl group, 2-pyridyl group, 2-indolyl group, 4-carbazolyl group, and 2-piperidyl group.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Specific examples of the organic photoconductive compound represented by the general formula (1) or (2) of the present invention include the following bisenamine compounds of E-01 to 20, but are not limited thereto. It is not a thing.
[0019]
[Chemical formula 5]

[0020]
[Chemical 6]

[0021]
[Chemical 7]

[0022]
[Chemical 8]

[0023]
The bis-enamine compound in the present invention is easily synthesized by the following synthesis route.
[0024]
That is, an enamine-aldehyde compound represented by the following general formula (3) and 0.5 mole equivalent of the bisphosphonate compound represented by the following general formula (4) with respect to (3) are converted into N, N- An amide solvent such as dimethylformamide or N, N-dimethylacetamide, a cyclic ether solvent such as dioxane or dioxolane, or an alcohol solvent such as ethanol or propanol is used. It can be easily synthesized by adding 0.5 molar equivalent of a base such as potassium t-butoxide or sodium methoxide and reacting at room temperature or heating at 50 to 100 ° C. for about 0.5 to 8 hours.
[0025]
[Chemical 9]

[0026]
Embedded image

[0027]
R in the general formula (3) ₁ , R ₂ , And Ar are the same as the bis-enamine compound represented by the general formula (1), and R in the general formula (4). _Three Represents a lower alkyl group such as a methyl group or an ethyl group.
[0028]
The enamine to aldehyde compound of the general formula (3) used as a synthesis raw material for the above reaction is R ₁ , R ₂ In the case where both are aryl groups, the method described in JP-A-11-43458 is used, and in other cases, Organic Synthesis Coll. Vol. III, acetaldehyde derivatives obtained using the methods described on pages 727-728 and 733-734 are condensed with a diamine compound in the presence of an acid catalyst such as p-toluenesulfonic acid to give an enamine compound. Is further formylated by the Vilsmeier reaction or the like.
[0029]
Moreover, about the bisphosphonate compound of General formula (4) which is one synthetic raw material, it reacts by heating 1, 4- dichloro- 2-butene with trialkyl phosphite of the following General formula (5). And can be easily obtained by distillation purification.
[0030]
Embedded image

[0031]
R in the general formula (5) _Three Is R in the general formula (4) _Three Is the same.
[0032]
Any of the forms of the electrophotographic photoreceptor including the photosensitive layer containing the organic photoconductive compound represented by the general formula (1) or (2) according to the present invention can be used. For example, there is one in which a photosensitive layer made of a charge generating substance, a charge transporting substance, and a film-forming binder resin is provided on a conductive support. There is also known a laminated type photoreceptor in which a charge generation layer made of a charge generation material and a binder resin and a charge transport layer made of a charge transport material and a binder resin are provided on a conductive support. . 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 of the present invention, a metal drum, a metal plate, a sheet of paper or plastic film subjected to conductive processing, a drum-like or belt-like support, and the like are used. The
[0033]
The electrophotographic photoreceptor of the present invention can be obtained by containing one or more of the organic photoconductive compound represented by the general formula (1) or (2) and the charge generating substance. The charge generation material includes an inorganic charge generation material and an organic charge generation material. Examples of the former include selenium, selenium-tellurium alloy, selenium-arsenic alloy, cadmium sulfide, zinc oxide, and amorphous silicon. Examples of organic charge generating materials include triphenylmethane dyes such as methyl violet, brilliant green and crystal violet, thiazine dyes such as methylene blue, quinone dyes such as quinizarin, cyanine dyes, acridine dyes, pyrylium dyes, thiapyrylium dyes , Squalium dyes, perinone pigments, anthraquinone pigments, perylene pigments, metal-containing or metal-free phthalocyanine pigments, and azo pigments are also used.
[0034]
Examples of the azo pigment include JP-A-47-37543, JP-A-53-95033, JP-A-53-132347, JP-A-53-133445, and JP-A-54-12742. JP-A-54-20736, JP-A-54-20737, JP-A-54-21728, JP-A-54-22834, JP-A-55-69148, JP-A-55. JP-A-69654, JP-A-55-79449, JP-A-55-117151, JP-A-56-46237, JP-A-56-1116039, JP-A-56-11640, JP-A-56-119134, JP-A-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-A-57-74746, JP-A-57-78542, JP-A-57- 78543, JP-A-57-90056, JP-A-57-90057, JP-A-57-90632, JP-A-57-116345, JP-A-57-202349, Japanese Laid-Open Patent Publication Nos. 58-4151, 58-90644, 58-144358, 58-177955, 59-19662, 59-33253 JP, 59-71059, 59-72448, 59-78356, 59-136351, 59-201060. JP, 60-15642, JP 60-14351, JP 60-179746, JP 61-11754, JP 61-90164, JP JP 61-90165, JP 61-90166, JP 61-112154, JP 61-269165, 61-281245, 61-51063 JP, 62-267363, JP 63-68844, JP 63-89866, JP 63-139355, JP 63-142033, JP 63 -183450, JP-A 63-282743, JP-A 64-21455, JP-A 64-78259, JP-A 1-200267, JP-A 1-2 No. 02757, JP-A-1-319754, JP-A-2-72372, JP-A-2-254467, JP-A-3-95561, 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-7-168379, etc. And the compounds described in the above.
[0035]
Moreover, the structure of the coupler component used in these azo pigments varies widely. For example, JP-A-54-17735, JP-A-54-79632, JP-A-57-176055, JP-A-59-97043, JP-A-60-130746, JP-A-60- -153050, JP-A-60-103048, JP-A-60-189759, JP-A-63-131146, JP-A-63-155052, JP-A-2-11069, Examples thereof include compounds described in Kaihei 4-149448, JP-A-6-27705, JP-A-6-348047, and the like.
[0036]
Specific examples of the azo pigment include compounds shown in Tables 1 to 45 below, but are not limited thereto. It is also possible to use these compounds in combination with other charge generation materials.
[0037]
[Table 1]

[0038]
[Table 2]

[0039]
[Table 3]

[0040]
[Table 4]

[0041]
[Table 5]

[0042]
[Table 6]

[0043]
[Table 7]

[0044]
[Table 8]

[0045]
[Table 9]

[0046]
[Table 10]

[0047]
[Table 11]

[0048]
[Table 12]

[0049]
[Table 13]

[0050]
[Table 14]

[0051]
[Table 15]

[0052]
[Table 16]

[0053]
[Table 17]

[0054]
[Table 18]

[0055]
[Table 19]

[0056]
[Table 20]

[0057]
[Table 21]

[0058]
[Table 22]

[0059]
[Table 23]

[0060]
[Table 24]

[0061]
[Table 25]

[0062]
[Table 26]

[0063]
[Table 27]

[0064]
[Table 28]

[0065]
[Table 29]

[0066]
[Table 30]

[0067]
[Table 31]

[0068]
[Table 32]

[0069]
[Table 33]

[0070]
[Table 34]

[0071]
[Table 35]

[0072]
[Table 36]

[0073]
[Table 37]

[0074]
[Table 38]

[0075]
[Table 39]

[0076]
[Table 40]

[0077]
[Table 41]

[0078]
[Table 42]

[0079]
[Table 43]

[0080]
[Table 44]

[0081]
[Table 45]

[0082]
As the phthalocyanine pigment used in the present invention, any of phthalocyanines known per se and derivatives thereof can be used. Specifically, metal-free phthalocyanines, titanyloxyphthalocyanines, copper phthalocyanines, aluminum phthalocyanines, diphenoxy Germanium phthalocyanines, germanium phthalocyanines, gallium phthalocyanines, chlorogallium phthalocyanines, bromogallium phthalocyanines, chloroindium phthalocyanines, bromoindium phthalocyanines, iodoindium phthalocyanines, magnesium phthalocyanines, chloroaluminum phthalocyanines, bromoaluminum phthalocyanines , Tin phthalocyanines, dichlorotin phthalocyanines, vanadyloxy Tarocyanines, zinc phthalocyanines, cobalt phthalocyanines, nickel phthalocyanines, hydroxygallium phthalocyanines, dihydroxygallium phthalocyanines, barium phthalocyanines, beryllium phthalocyanines, cadmium phthalocyanines, chlorocobalt phthalocyanines, dichlorotitanyl phthalocyanines, iron phthalocyanines Silicon phthalocyanines, lead phthalocyanines, platinum phthalocyanines, metal-free naphthalocyanines, aluminum naphthalocyanines, titanyloxynaphthalocyanines, ruthenium phthalocyanines, palladium phthalocyanines, and the like. Among these, metal-free phthalocyanine, titanyloxyphthalocyanine, copper phthalocyanine, chloroaluminum phthalocyanine, chloroindium phthalocyanine, vanadyloxyphthalocyanine, diphenoxygermanium phthalocyanine, chlorogallium phthalocyanine, and hydroxygallium phthalocyanine are preferably used in the present invention.
[0083]
Moreover, phthalocyanine pigments are known as crystalline polymorphic compounds, and various crystalline phthalocyanine pigments have been found. As a description of these crystal types and production methods, metal-free phthalocyanines are disclosed in JP-B-49-4338, JP-A-58-182639, JP-A-60-19151, and JP-A-62-47054. JP-A-62-143058, JP-A-63-286857, JP-A-1-138563, JP-A-1-230581, JP-A-2-233769, and J. Org. Phys. Chem. 72 3230 (1968).
[0084]
Titanyloxyphthalocyanine is disclosed in JP-A-61-217050, JP-A-62-267094, JP-A-62-229253, JP-A-63-364, JP-A-63-365, JP-A 63-366, JP-A 63-37163, JP-A 63-80263, JP-A 63-116158, JP-A 63-198067, JP-A 63- No. 218768, JP-A 64-17066, JP-A 1-123868, JP-A 1-1138562, JP-A 1-153757, JP-A 1-172459, JP-A 1-172462. No. 1, JP-A-1-189200, JP-A-1-204969, JP-A-1-207755, JP-A-1-299874, -8256, JP-A-2-99969, JP-A-2-131243, JP-A-2-165156, JP-A-2-165157, JP-A-2-215866, JP-A-2-267563. No. 2, JP-A-2-297560, JP-A-3-35064, JP-A-3-54264, JP-A-3-84068, JP-A-3-94264, JP-A-3-100168. JP-A-3-100699, JP-A-3-123359, JP-A-3-199268, JP-A-3-200790, JP-A-3-269064, JP-A-4-145166, No. 4-145167, JP-A-4-153273, JP-A-4-159373, JP-A-4-179964 JP-A-5-202309, JP-A-5-279592, JP-A-5-289380, JP-A-6-336554, JP-A-7-82503, JP-A-7-82505, Include those described in JP-A-8-110649.
[0085]
Further, copper phthalocyanine includes those described in JP-B-52-1667, JP-A-51-108847, JP-A-55-60958, and γ-type, π-type, χ-type, ρ type and the like are known and can be mentioned. Chloroaluminum phthalocyanine is disclosed in JP-A-58-158649, JP-A-62-133462, JP-A-62-163060, JP-A-63-43155, and JP-A-64-70762. In the publication, chloroindium phthalocyanine is disclosed in JP-A-59-44054, JP-A-60-59355, JP-A-61-45249, and further in JP-A-7-13375. In JP-A-63-18361, JP-A-1-204968, JP-A-1-268863, JP-A-3-269663, and further in JP-A-7-247442, diphenoxygermanium phthalocyanine is JP-A-4-360150 discloses chlorogallium phthalocyanine as JP-A-5-1. 4523 JP, even in JP-A-7-102183, hydroxygallium phthalocyanine, JP-A-5-263007, JP-even can be exemplified those described in JP-A-7-53892.
[0086]
The film-forming binder resin used for forming the photosensitive layer containing the organic photoconductive compound represented by the general formula (1) or (2) of the present invention includes various types depending on the application field. For example, in the use of photoconductors for copying, 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 or polyvinyl chloride resin. Among these, polystyrene resin, polyvinyl acetal resin, polycarbonate resin, polyester resin, polyarylate resin, and the like are excellent in potential characteristics as a photoreceptor. In addition, these resins may be either single or copolymer and may be used alone or in combination of two or more thereof. The amount of the binder resin added to the photoconductive compound is preferably 20 to 1000% by weight, and more preferably 50 to 500% by weight.
[0087]
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 decreases, 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.
[0088]
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, and chlorinated hydrocarbons. When these substances are added more than necessary, the electrophotographic properties are adversely affected, and therefore the ratio is preferably 20% by weight or less based on the binder resin.
[0089]
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.
[0090]
The compound represented by the general formula (1) or (2) can be used in combination with another charge transport material. Charge transport materials include hole transport materials and electron transport materials. Examples of the former include, for example, oxadiazoles shown in Japanese Patent Publication No. 34-5466, triphenylmethanes shown 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. These charge transport materials can be used alone or in combination of two or more.
[0091]
Further, as a sensitizer that forms a charge transfer complex with the compound represented by the general formula (1) or (2) and further increases the sensitizing effect, a certain kind of electron withdrawing compound can be added. Examples of the electron-withdrawing compound include quinones such as 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 1-chloro-5-nitroanthraquinone, 2-chloroanthraquinone, phenanthrenequinone, and 4-nitro. Aldehydes such as benzaldehyde, ketones such as 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 3,3 ', 5,5'-tetranitrobenzophenone, phthalic anhydride, 4-chloronaphthalic anhydride, etc. Acid anhydrides, terephthalalmalononitrile, 9-anthrylmethylidenemalononitrile, 4-nitrobenzalmalononitrile, cyano compounds such as 4- (p-nitrobenzoyloxy) benzalmalononitrile, 3-benzalphthalide, 3 -(Α-cyano-p-ni Robenzaru) phthalide, 3- (alpha-cyano -p- Nitorobenzaru) -4,5,6,7 such phthalides such as tetrachloro phthalide can be cited.
[0092]
The organic photoconductive compound of the present invention is dissolved or dispersed in an appropriate solvent together with the above-mentioned various additives depending on the form of the photoreceptor, and the coating solution is applied onto the conductive support described above. The photosensitive member can be manufactured by drying.
[0093]
Coating solvents include halogenated hydrocarbons such as chloroform, dichloroethane, dichloromethane, trichloroethane, trichloroethylene, chlorobenzene and dichlorobenzene, aromatic hydrocarbons such as benzene, toluene and xylene, dioxane, tetrahydrofuran, methyl cellosolve, ethyl cellosolve, ethylene glycol dimethyl ether. Ether solvents such as methyl ethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone, cyclohexanone and other ketone solvents, ethyl acetate, methyl formate, methyl cellosolve acetate and other ester solvents, N, N-dimethylformamide, acetonitrile, N-methyl Aprotic polar solvents such as pyrrolidone and dimethyl sulfoxide, and n-butanol and 2-propanol Or the like can be mentioned alcohol-based solvent. These solvents can be used alone or as a mixed solvent of two or more.
[0094]
【Example】
EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited to these at all.
[0095]
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[0096]
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[0097]
Synthesis Example 1 Synthesis of Exemplary Compound (E-14)
1a) Synthesis of enamine-aldehyde compound ((6) above)
While 27 ml of N, N-dimethylformamide is being stirred under ice cooling, 17.2 ml of phosphorus oxychloride is slowly added dropwise to prepare a Vilsmeier reagent. While stirring the above-mentioned Vilsmeier reagent under ice-cooling, 12.0 g of the enamine compound (7) (the synthesis method is described in JP-A-11-43458) was dissolved in 240 ml of N, N-dimethylformamide. The solution was added dropwise, stirred at room temperature for 15 minutes, and then stirred at 90 ° C. for 4 hours. The reaction solution was poured into 200 ml of ice water and neutralized with 2N aqueous sodium hydroxide solution, and then the precipitated crystals were collected by filtration, washed with water, washed with methanol, and recrystallized with acetonitrile to obtain 9.09 g of (6). . The yield was 70.2%, and the melting point was 149 to 150 ° C.
[0098]
1b) Synthesis of bisphosphonate compound (following (8))
After 14 g of 1,4-dichloro-2-butene and 40 g of triethyl phosphite were heated to 140 ° C. with stirring and reacted for 6 hours, triethyl phosphite was removed under reduced pressure to give an oily (8 ) 27.34 g was obtained. The yield was 74.4%.
[0099]
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[0100]
1c) Synthesis of exemplary compound (E-14)
To a solution of N, N-dimethylformamide 50 ml in which (6) 8.3 g and (8) 3.29 g were dissolved, 3.72 g of potassium t-butoxide was slowly added with stirring at room temperature. After stirring at room temperature all day and night, the reaction solution was poured into 250 ml of ice water to stop the reaction. After stirring for a while at room temperature, the resulting brown crystals were extracted with chloroform. The organic layer was separated and dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The obtained oily substance was purified by silica gel column chromatography (elution solvent: toluene) to obtain 2.61 g of the objective compound (E-14). The yield was 33.9% and the melting point was 79-84 ° C.
[0101]
This thing is ¹ H-NMR (δ, ppm, CDCl _Three ), 7.4-6.8 (m, 28H), 6.71 (t, 8H), 6.47 (d, 4H), 6.41 (d, 4H), 6.14 (d, 2H) ), The structure was confirmed.
[0102]
Example 1
1 part by weight of the azo pigment (K-2) and 1 part by weight of a polyester resin (Toyobo Byron 200) were mixed with 100 parts by weight of tetrahydrofuran, and dispersed with glass beads in a paint conditioner device for 2 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 exemplified compound (E-14) of the present invention is mixed with polyarylate resin (U-polymer manufactured by Unitika) at a weight ratio of 1: 1 to make a 10 wt% solution using dichloroethane as a solvent, A charge transport layer having a thickness of about 20 μm was formed on the generation layer by application with an applicator.
[0103]
The multilayer photoconductor produced in this manner was evaluated for electrophotographic characteristics using an electrostatic recording test apparatus (EPA-8200 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 (V ₀ ) Was -720 V, and the half exposure (E1 / 2) was 1.1 lux.sec.
[0104]
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 due to repetition at 5000 times was determined, the first charging potential (V ₀ ) -720V vs. 5000th charging potential (V ₀ ) Was −710 V, and showed stable characteristics with almost no decrease in potential due to repetition. In addition, the first half-exposure dose (E1 / 2) was 1.1 lux · second, and the 5000th half-exposure dose (E1 / 2) was 1.1 lux · second, indicating no change. .
[0105]
Examples 2-11
Example 1 and Example 1 were used except that the azo pigment shown in Table 46 and the exemplified compound of the present invention were used instead of the azo pigment (K-2) of Example 1 and the exemplified compound (E-14) of the present invention. Similarly, a photoconductor was prepared and its characteristics were evaluated. The results are shown in Table 46.
[0106]
[Table 46]

[0107]
Example 12
One part by weight of the azo pigment (H-1) and 40 parts by weight of tetrahydrofuran were dispersed with a glass bead for 8 hours using a paint conditioner. To the dispersion thus obtained, 2.5 parts by weight of the exemplary compound (E-14) of the present invention, 10 parts by weight of a polycarbonate resin (PCZ-200 manufactured by Mitsubishi Gas Chemical) and 60 parts by weight of tetrahydrofuran are added, and a paint conditioner device is further added. After 30 minutes of dispersion treatment, it was coated on aluminum vapor-deposited polyester with an applicator to form a photosensitive layer 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 ) + 450V, half-exposure dose (E1 / 2) 1.3 lux · sec. ₀ ) + 440V, half-exposure amount (E1 / 2) 1.3 lux · second, high sensitivity and little change.
[0108]
Examples 13-22
The same procedure as in Example 12, except that the azo pigment shown in Table 47 and the exemplified compound of the present invention were used instead of the azo pigment (H-1) of Example 12 and the exemplified compound (E-14) of the present invention, respectively. Thus, a photoconductor was prepared and its characteristics were evaluated. The results are shown in Table 47.
[0109]
[Table 47]

[0110]
Examples 23-27
Instead of the azo pigment (K-2) of Example 1, the Bragg angle (2θ ± 0.2 °) with respect to X-ray of CuKα1.541 Å is 9.5 °, 9.7 °, 11.7 °, 15 Titanyloxyphthalocyanine (Y-type titanyloxyphthalocyanine) having an X-ray diffraction spectrum showing main peaks at 0.0 °, 23.5 °, 24.1 °, and 27.3 ° is also shown in Table 48 as a charge transport material. A photoconductor was prepared in the same manner as in Example 1 except that the exemplified compounds of the present invention were used, and the characteristics thereof were evaluated. The results are shown in Table 48.
[0111]
[Table 48]

[0112]
Examples 28-32
Photoconductor in the same manner as in Example 12 except that Y-type titanyloxyphthalocyanine was used instead of the azo pigment (H-1) of Example 12 and the exemplary compound of the present invention shown in Table 49 was used as the charge transport material. Were fabricated and their characteristics were evaluated. The results are shown in Table 49.
[0113]
[Table 49]

[0114]
Comparative Example 1
A photoconductor was prepared and evaluated in the same manner as in Example 1 except that the following compound (R-1) was used instead of the exemplified compound (E-14) of the present invention as a charge transport material. As a result, the first charging potential (V ₀ ) -660V vs. 5000th charging potential (V ₀ ) Is −410 V, and the initial charging potential was poor, and a significant decrease in potential due to repetition was observed. In addition, the first half exposure (E1 / 2) was 2.7 lux · sec, and the 5000th half exposure (E1 / 2) was 4.7 lux · sec.
[0115]
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[0116]
Comparative Example 2
Similarly, the photoconductor was prepared in the same manner as in Example 1 except that the following comparative compound (R-2 to 4) was used instead of the exemplified compound (E-14) of the present invention as the charge transport material. Fabricated and evaluated. As shown in Table 50, all the results showed a decrease in sensitivity and a decrease in charging potential due to repetition.
[0117]
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[0118]
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[0119]
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[0120]
[Table 50]

[0121]
【The invention's effect】
As is apparent from the above, an excellent electrophotographic photoreceptor having high sensitivity and high durability can be provided by using the organic photoconductive compound of the present invention.

Claims (6)

An organic photoconductive compound represented by the following general formula (1).

(In General Formula (1), R1 and R2 represent a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group, an aryl group, or a heterocyclic group, and Ar may have a substituent. A good aryl group or heterocyclic group.) An electrophotographic photosensitive member characterized by having a photosensitive layer containing at least one organic photoconductive compound represented by the following general formula (1) on the conductive support.

(In General Formula (1), R1 and R2 represent a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group, an aryl group, or a heterocyclic group, and Ar may have a substituent. A good aryl group or heterocyclic group.) 3. The photosensitive layer contains a charge generation material and a charge transport material, and the charge transport material is at least one of the organic photoconductive compounds represented by the general formula (1). Electrophotographic photoreceptor. The organic photoconductive compound of Claim 1 shown by following General formula (2).

(In general formula (2), R1 and R2 are the same as in general formula (1).) The electrophotographic photosensitive member according to claim 2, characterized in that it comprises a photosensitive layer containing at least one organic photoconductive compound represented by the following general formula (2) on the electrically conductive substrate.

(In general formula (2), R1 and R2 are the same as in general formula (1).) 6. The photosensitive layer contains a charge generation material and a charge transport material, and the charge transport material is at least one organic photoconductive compound represented by the general formula (2). Electrophotographic photoreceptor.