JP3600455B2 - Electrophotographic photoreceptor - Google Patents

Description

【００１１】
（上記一般式［１］中、Ａ、Ｂ、Ｃ、Ｄ、ＥおよびＦは、置換基を有してもよいベンゼン環を表わし、これらは互いに結合して複素環を形成してもよく；Ｙは、置換基を有してもよい二価の脂肪族炭化水素残基を表わし；
Ｘ^１ およびＸ^２ は、それぞれ、下記一般式［２］および一般式［３］で示される基を表わし、これらはそれぞれ同一でも異なっていてもよい。）
【００１２】
【化４】

【００１３】
（上記一般式［２］および［３］中、ｎ_３ は、１ないし４の整数を表わし；ｎ_４ は、１ないし４の整数を表わし；Ｒ^５ 、Ｒ^６ 、Ｒ^７ 、Ｒ^８ 、Ｒ^９ 、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３およびＲ^１４は、それぞれ、水素原子、シアノ基、ニトロ基、置換基を有してもよいアルキル基、置換基を有してもよいアリール基または置換基を有してもよい複素環基を表わし、これらは互いに同一でも異なっていてもよく、Ｒ^８ とＲ^９ からなる対およびＲ^１３とＲ^１４からなる対は、縮合して炭素環基または複素環基を形成していてもよく、また、これらの対のＲのどちらか一方が水素原子のときは、もう一方はアリール基または複素環基である。）
【００１４】
【発明の実施の形態】
以下、本発明を詳細に説明する。
本発明の電子写真感光体は、感光層中に前記一般式［１］で表わされるアリールアミン系化合物を含有する。
【００１５】
前記一般式［１］中、Ａ、Ｂ、Ｃ、Ｄ、ＥおよびＦは、それぞれ、ベンゼン環を表わし、これらはお互いに結合して、Ａ、Ｂ、Ｃのいずれか二者間にまたはＤ、Ｅ、Ｆのいずれか二者間に、
単結合、メチレン基、エチレン基、カルボニル基、ビニリデン基、エチレニレン基等を介した窒素原子を含む複素環を形成してもよく、所望ならば、さらに酸素原子、硫黄原子、窒素原子等を含む、複素環を形成してもよい。
【００１６】
これらのベンゼン環は、置換基を有してもよく、置換基としては、
水酸基；
フッ素原子、塩素原子、臭素原子、沃素原子等のハロゲン原子；
メチル基、エチル基、プロピル基、ブチル基、ヘキシル基、イソプロピル基等のアルキル基；
メトキシ基、エトキシ基、プロピルオキシ基等のアルコキシ基；
アリル基、ビニル基、ブテニル基等のアルケニル基；
ベンジル基、ナフチルメチル基、フェネチル基等のアラルキル基；
フェノキシ基、トリロキシ基等のアリールオキシ基；
ベンジルオキシ基、フェネチルオキシ基等のアリールアルコキシ基；
フェニル基、ナフチル基等のアリール基；
アセチル基、ベンゾイル基等のアシル基；
ジメチルアミノ基、ジエチルアミノ基等のジアルキルアミノ基、
ジフェニルアミノ基、ジナフチルアミノ基等のジアリールアミノ基、
ジベンジルアミノ基、ジフェネチルアミノ基等のジアラルキルアミノ基、
ジピリジルアミノ基、ジチエニルアミノ基等のジ複素環アミノ基、
ジアリルアミノ基等のジ置換アミノ基、または、これらのジ置換アミノ基の置換基の一方を別の置換基または水素原子に変えたジ置換アミノ基またはモノ置換アミノ基等の置換アミノ基等があげられる。
それぞれのベンゼン環が有する置換基は、単数でも複数でもよく、また、複数の場合は、互いに同一でも異なっていてもよく、さらに、これらの置換基はお互いに縮合して、それぞれのベンゼン環上の異なる位置間に、
単結合、メチレン基、エチレン基、カルボニル基、ビニリデン基、エチレニレン基等を介した炭素環を形成してもよく、所望ならば、酸素原子、硫黄原子、窒素原子等を含む、複素環基を形成してもよい。
【００１７】
前記一般式［１］中、Ｙは、メタン、エタン、プロパン、シクロヘキサン、シクロペンタン等の脂肪族炭化水素から２個の水素原子を除いた、二価の残基であり、具体的には、メチレン基、エチレン基、プロピレン基、シクロヘキシリデン基等が挙げられるが、水素原子を除く位置は、炭化水素を構成する炭素原子のうち、同一または異なる炭素原子のいずれでもよい。また、脂肪族炭化水素残基はとくに脂環状炭化水素残基、例えばシクロヘキシリデン基が好ましい。
【００１８】
これら二価の残基は、炭素環上または炭素鎖上に置換基を有していてもよく、置換基は、単数でも複数でもよく、また、複数の場合は、互いに同一でも異なっていてもよく、さらに、これらの置換基はお互いに縮合して、それぞれの環または鎖上の異なる位置間にまたは別の環または鎖との間に、炭素環または複素環を形成してもよい。さらにそれらの縮合形成された環も、置換基を有していてもよい。
上記二価の残基または縮合形成された環が有する置換基としては、
メチル基、エチル基、プロピル基、ブチル基、ヘキシル基、イソプロピ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；
シアノ基；
アルコキシカルボニル基；
アリールオキシカルボニル基；
ニトロ基；
フッ素原子、塩素原子、臭素原子、沃素原子等のハロゲン原子等があげられる。
【００１９】
また、一般式［１］中、Ｘ^１ は、下記一般式［２］で示される基を表わし、
Ｘ^２ は、下記一般式［３］で示される基を表わし、これらはそれぞれ同一でも異なっていてもよい。
【００２０】
【化５】

【００２１】
一般式［２］および［３］中、ｎ_３ は、１ないし４の整数を表わし；ｎ_４ は、１ないし４の整数を表わす。ｎ_３ およびｎ_４ は、溶解性の面から、１ないし２が好ましい。
【００２２】
また、Ｒ^５ 、Ｒ^６ 、Ｒ^７ 、Ｒ^８ 、Ｒ^９ 、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３およびＲ^１４は、
それぞれ、水素原子；シアノ基；ニトロ基；
メチル基、エチル基、プロピル、イソプロピル基等のアルキル基；
フェニル基、ナフチル基、ピレニル基等のアリール基；
ピリジル基、チエニル基等の複素環基等を表し、
これらは互いに同一でも異なっていてもよく、
特に、水素原子、メチル基、フェニル基が好ましい。
【００２３】
これらのアルキル基、アリール基、複素環基は置換基を有していてもよく、
置換基としては、
水酸基；
フッ素原子、塩素原子、臭素原子、沃素原子等のハロゲン原子；
メチル基、エチル基、プロピル基、ブチル基、ヘキシル基、イソプロピル基等のアルキル基；
メトキシ基、エトキシ基、プロピルオキシ基等のアルコキシ基；
アリル基、ビニル基、ブテニル基等のアルケニル基；
ベンジル基、ナフチルメチル基、フェネチル基等のアラルキル基；
フェノキシ基、トリロキシ基等のアリールオキシ基；
ベンジルオキシ基、フェネチルオキシ基等のアリールアルコキシ基；
フェニル基、ナフチル基等のアリール基；
スチリル基、ナフチルビニル基等のアリールビニル基；
アセチル基、ベンゾイル基等のアシル基；
ジメチルアミノ基、ジエチルアミノ基等のジアルキルアミノ基、
ジフェニルアミノ基、ジナフチルアミノ基等のジアリールアミノ基、
ジベンジルアミノ基、ジフェネチルアミノ基等のジアラルキルアミノ基、
ジピリジルアミノ基、ジチエニルアミノ基等のジ複素環アミノ基、
ジアリルアミノ基等のジ置換アミノ基、または、これらのジ置換アミノ基の置換基の一方を別の置換基または水素原子に変えたジ置換アミノ基またはモノ置換アミノ基等の置換アミノ基等があげられる。
アルキル基、アリール基、複素環基が有する上記各種の置換基は、単数でも複数でもよく、また、複数の場合は、これら置換基がお互いに縮合して、同一のＲ^５ 、Ｒ^６ 、Ｒ^７ 、Ｒ^８ 、Ｒ^９ 、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３若しくはＲ^１４内に、異なるＲ^５ 、Ｒ^６ 間に、異なるＲ^１０、Ｒ^１１間に、Ｒ^７ とＲ^５ 、Ｒ^６ との間にまたはＲ^１２とＲ^１０、Ｒ^１１との間に、
単結合、メチレン基、エチレン基、カルボニル基、ビニリデン基、エチレニレン基等を介した炭素環を形成してもよく、所望ならば、酸素原子、硫黄原子、窒素原子等を含む、複素環を形成してもよい。
ただし、Ｒ^８ とＲ^９ からなる対およびＲ^１３とＲ^１４からなる対は、縮合して炭素環基または複素環基を形成していてもよく、また、これらの対のＲのどちらか一方が水素原子のときは、もう一方はアリール基または複素環基である。
【００２４】
以下に、一般式［１］で表わされるアリールアミン系化合物について、その代表例を例示のために列挙する。もちろん、本発明に用いるアリールアミン系化合物が、これら代表例のみに限定されるものではない。なお、以下の例示においては、一般式［１］に倣い、化合物の構造式と置換基Ｘ１、Ｘ２とに分けて表示し、置換基のみが相違する化合物の場合は、２番目以降の化合物については置換基Ｘ１、Ｘ２のみを表示した。
【００２５】
【化６】

【００２６】
【化７】

【００２７】
【化８】

【００２８】
【化９】

【００２９】
【化１０】

【００３０】
【化１１】

【００３１】
【化１２】

【００３２】
【化１３】

【００３３】
【化１４】

【００３４】
【化１５】

【００３５】
【化１６】

【００３６】
【化１７】

【００３７】
【化１８】

【００３８】
【化１９】

【００３９】
【化２０】

【００４０】
【化２１】

【００４１】
【化２２】

【００４２】
前記一般式［１］で表わされるアリールアミン系化合物は、公知の方法を用いて、製造できる。例えば、公知のアリールアミン系化合物を原料として用いて、公知のカルボニル導入反応を行い、次いで、Ｗｉｔｔｉｇ反応を行うことにより、目的の化合物を得る方法である。
この方法を詳しく説明すると、まず、カルボニル導入反応は、下記の反応式で示される。
【００４３】
【化２３】

【００４４】
上記のカルボニル導入反応を示す反応式および後記のＷｉｔｔｉｇ反応を示す反応式において、環Ａ、Ｂ、Ｃ、Ｄ、ＥおよびＦ、基Ｒ^５ 、Ｒ^６ 、Ｒ^７ 、Ｒ^８ 、Ｒ^９ 、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｙ、Ｘ^１ およびＸ^２ 並びに添字ｎ_３ およびｎ_４ は、前述の一般式［１］、［２］、［３］におけるものと同一の意義を有する。
【００４５】
１）Ｒ^５ ＝Ｒ^１０＝Ｈの場合：
一般式［４］で表わされるアリールアミン系化合物を、オキシ塩化リンの存在下に、Ｎ，Ｎ−ジメチルホルムアミド、Ｎ−メチルホルムアニリド等のホルミル化剤と反応させると、一般式［５］で示されるアルデヒド体が得られる。その際、ホルミル化剤を大過剰に用いて、反応溶媒を兼ねることもできるが、Ｏ−ジクロロベンゼン、ベンゼン等の反応に不活性な溶媒を用いることもできる。
【００４６】
２）Ｒ^５ 、Ｒ^１０≠Ｈの場合
一般式［４］で表わされるアリールアミン系化合物を、塩化アルミニウム、塩化鉄、塩化亜鉛等のルイス酸存在下、ニトロベンゼン、ジクロルメタン、四塩化炭素等の溶媒中、一般式Ｃｌ−ＣＯ−Ｒ^５ で表わされる酸塩化物および一般式Ｃｌ−ＣＯ−Ｒ^１０で表わされる酸塩化物と、反応させることにより一般式［５］で表わされるケトン体が得られる。
【００４７】
次いで、カルボニル導入反応で得られた、一般式［５］で表わされるアルデヒド体またはケトン体と、Ｎ，Ｎ−ジメチルホルムアミド、Ｎ，Ｎ−ジメチルアセトアミド、テトラヒドロフラン、ジオキサン、ベンゼン、トルエン等の反応に不活性な公知の有機溶媒中で、一般式［６］、［６’］（両式中、Ｑは塩素原子、臭素原子等のハロゲン原子を示す。）で表わされるハロゲン化合物にトリフェニルホスフィンまたはトリアルコキシリン化合物（Ｒ^１５Ｏ）_３ Ｐ（Ｒ^１５はメチル基、エチル基等のアルキル基をあらわす。）を作用させて得られるＷｉｔｔｉｇ試薬とを、１０〜２００℃、好ましくは２０〜１００℃の温度で、ブチルリチウム、フェニルリチウム、ナトリウムメトキシド、ナトリウムエトキシド、カリウムｔ−ブトキシド等の公知な塩基性触媒の存在下反応させることにより、一般式［１］で表わされるアリールアミン系化合物が得られる。
このＷｉｔｔｉｇ反応は、下記の反応式で示される。
【００４８】
【化２４】

【００４９】
この時、一般式［１］で表わされるアリールアミン系化合物としては、シス体、トランス体およびシス体とトランス体との混合物のいずれかが得られる。
これらの反応において、場合によっては、各工程終了後または全工程終了後に、再結晶精製、再沈精製、昇華精製、カラム精製等の公知な精製手段により、高純度体を得ることも可能である。
【００５０】
本発明の電子写真感光体は、導電性支持体上に、上記一般式［１］で表わされるアリールアミン系化合物を、１種または２種以上含有する感光層（光伝導層）を有する。しかして、一般式［１］で表わされるアリールアミン系化合物は、有機光伝導体として極めて優れた性能を示す。特に、電荷輸送媒体として用いた場合には、高感度で耐久性に優れた感光体を与える。
【００５１】
本発明の電子写真感光体において、感光層は、上記一般式［１］で表わされるアリールアミン系化合物を含有するものであれば、任意の形態をとることができる。すなわち、感光層は、光を吸収すると極めて高い効率で電荷キャリヤーを発生する電荷発生材料を含有する電荷発生層および電荷キャリヤーを輸送する電荷輸送材料を含有する電荷輸送層を、この順にまたは逆の順に積層形成したいわゆる積層型でもよいし、また電荷輸送材料を含有する分散媒体中に電荷発生材料の粒子を分散させた層を形成したいわゆる分散型でもよい。
【００５２】
本発明においては、上記一般式［１］で表わされる、アリールアミン系化合物を、電荷発生層と電荷輸送層の２層からなる積層型感光層の、電荷輸送層中に用いる場合に、特に感度が高く、残留電位が小さく、かつ、繰り返し使用した場合に、表面電位の変動や感度の低下、残留電位の蓄積等が少なく、耐久性に優れた感光体を得ることができる。
【００５３】
本発明の電子写真感光体に使用する電荷発生材料としては、特に制限はなく、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、アモルファスシリコン等の無機光伝導性粒子；無金属フタロシアニン、金属含有フタロシアニン、ペリノン系顔料、チオインジゴ、キナクリドン、ペリレン系顔料、アントラキノン系顔料、モノアゾ系顔料、ビスアゾ系顔料、トリスアゾ系顔料、ポリアゾ系顔料、シアニン系顔料等の有機光伝導性粒子が挙げられる。さらに、多環キノン、ピリリウム塩、チオピリリウム塩、インジゴ、アントアントロン、ピラントロン等の各種有機色素も使用できる。
【００５４】
これらの電荷発生材料の中では、無金属フタロシアニン；銅、塩化インジウム、塩化ガリウム、錫、オキシチタニウム、亜鉛、バナジウム等の金属またはその酸化物、塩化物の配位した金属含有フタロシアニン；モノアゾ、ビスアゾ、トリスアゾ、ポリアゾ系等のアゾ顔料が好ましい。
【００５５】
中でも、金属含有フタロシアニンおよび無金属フタロシアニンは、前記一般式［１］で示されるアリールアミン系化合物と組合せた場合、レーザー光に対する感度が向上した感光体が得られるので、好ましい。
とりわけ、ａ）Ｘ線回折スペクトルのブラッグ角（２θ±０．２°）９．７°、１４．２°および２７．３°に回折ピークを示すオキシチタニウムフタロシアニン、ｂ）Ｘ線回折スペクトルのブラッグ角（２θ±０．２°）９．３°、１３．２°、２６．２°および２７．１°に回折ピークを示すオキシチタニウムフタロシアニンまたはｃ）Ｘ線回折スペクトルのブラッグ角（２θ±０．３゜）９．２°、１４．１°、１５．３°、１９．７°および２７．１゜に回折ピークを有するジヒドロキシシリコンフタロシアニン化合物を含有する電子写真感光体は、高感度で、残留電位が低く帯電性が高く、かつ、繰返しによる変動が小さく、特に、画像濃度に影響する帯電安定性が良好であることから、高耐久性感光体として用いることができる。また、７５０〜８５０ｎｍの領域の感度が高いことから、特に半導体レーザープリンター用感光体に適している。
【００５６】
前記ａ）のオキシチタニウムフタロシアニンの製造方法は特に限定されないが、例えば以下の方法で製造される。
１ 特開昭６２−６７０９４号公報製造例１中に記載されている〔ＩＩ〕型結晶の製造方法。つまり、オルトフタロジニトリルとチタンのハロゲン化物とを、不活性有機溶剤中で加熱して反応させ、次いで加水分解する。
２ 各種結晶型のオキシチタニウムフタロシアニンを、直接または有機酸溶媒中、硫酸または式Ｒ−ＳＯ_３ Ｈ（式中、Ｒは、置換基を有していてもよい、脂肪族または芳香族残基を表わす。）で表わされるスルホン化物で加熱処理するとか、場合によっては、その後不溶性有機溶媒と水との混合溶媒で加熱処理する。
３ 所望により、あらかじめ濃硫酸に溶解後氷水中に放出するとか、ペイントシェーカー、ボールミル、サンドグラインドミル等の機械的摩砕法等の公知な方法により無定型化後、上記スルホン化物で加熱処理したり、水不溶性有機溶媒と水の混合溶媒にて加熱処理する。
４ 上述のスルホン化物との処理の場合、加熱処理のかわりに、ペイントシェーカー、ボールミル、サンドグラインドミル等の機械的摩砕法を併用する。
【００５７】
また、本発明において、電荷発生材料として２種以上のフタロシアニン化合物を併用することもできる。例えば、前記のＸ線回折スペクトルのブラッグ角（２θ±０．２°）９．７°、１４．２°および２７．３°に回折ピークを示すオキシチタニウムフタロシアニンとＸ線回折スペクトルのブラッグ角（２θ±０．２°）９．３°、１３．２°、２６．２°および２７．１°に回折ピークを示すオキシチタニウムフタロシアニンとを併用すること、または前記のＸ線回折スペクトルのブラッグ角（２θ±０．２°）９．７°、１４．２°および２７．３°に回折ピークを示すオキシチタニウムフタロシアニンとＸ線回折スペクトルのブラッグ角（２θ±０．２°）８．５°、１２．２°、１３．８°、１６．９°、２２．４°、２８．４°および３０．１°に回折ピークを示すジクロロスズフタロシアニンとを併用することは、感度の点で好ましい。
【００５８】
本発明の電子写真感光体は、常法に従って製造することができる。すなわち、上記の電荷発生材料および／または電荷輸送材料を、バインダーと共に適当な溶剤中に溶解し、必要に応じ、適当な増感染料、電子吸引性化合物、可塑剤等周知の添加剤を添加して得られる塗布液を、導電性支持体上に塗布、乾燥し、所定膜厚の感光層を形成させることにより製造することができる。電荷発生層と電荷輸送層の２層からなる積層型感光層の場合は、電荷発生材料および電荷輸送材料をそれぞれ別個の塗布液として準備し、順次塗布する必要があるが、分散型感光層の場合は、両材料を含む塗布液を塗布するだけでよい。もっとも、積層型感光層の電荷発生層は塗布によらず、蒸着によって形成することも可能である。
【００５９】
積層型感光層における電荷発生層に使用されるバインダー樹脂としては、例えばポリエステル樹脂、ポリビニルアセテート、ポリエステルポリカーボネート、ポリビニルアセトアセタール、ポリビニルプロピオナール、ポリビニルブチラール、フェノキシ樹脂、エポキシ樹脂、ウレタン樹脂、セルロースエステル、セルロースエーテル等が挙げられる。電荷発生材料等の微粒子を、各種バインダー樹脂で結着した形の分散層としうるものであれば制限はない。これらのほかに、スチレン、酢酸ビニル、塩化ビニル、アクリル酸エステル、メタクリル酸エステル、ビニルアルコール、エチルビニルエーテル等のビニル化合物の重合体および共重合体、ポリアミド、けい素樹脂等のバインダー樹脂も使用できる。この場合の電荷発生材料の使用比率は、バインダー樹脂１００重量部に対して、通常２０〜２０００重量部、好ましくは３０〜５００重量部、より好ましくは３３〜５００重量部の範囲より選択される。
【００６０】
積層型感光層の場合の電荷輸送層に使用されるバインダー樹脂、あるいは分散型感光層の場合のマトリックスとして使用されるバインダー樹脂としては、電荷輸送材料との相溶性が良く、塗膜形成後に電荷輸送材料が結晶化したり、相分離することのないポリマーが好ましく、例えば、スチレン、酢酸ビニル、塩化ビニル、アクリル酸エステル、メタクリル酸エステル、ブタジエン等のビニル化合物の重合体および共重合体、ポリビニルアセタール、ポリカーボネート、ポリエステル、ポリエステルカーボネート、ポリスルホン、ポリイミド、ポリフェニレンオキサイド、ポリウレタン、セルロースエステル、セルロースエーテル、フェノキシ樹脂、けい素樹脂、エポキシ樹脂等の各種ポリマーが挙げられ、またこれらの部分的架橋硬化物も使用できる。バインダーの使用量は、電荷輸送材料に対し、０．５〜３０重量倍、好ましくは０．７〜１０重量倍の範囲である。
【００６１】
塗布液調製用の溶剤としては、テトラヒドロフラン、１，４−ジオキサン、ジメトキシエタン等のエーテル類、メチルエチルケトン、４−メトキシ−４−メチルペンタノン−２、シクロヘキサノン等のケトン類；トルエン、キシレン等の芳香族炭化水素；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媒；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類；ジクロロエタン、クロロホルム等の塩素化炭化水素類が挙げられる。勿論、これらの中からバインダーを溶解するものを選択する必要がある。さらに、アリールアミン系化合物等の電荷輸送材料を含む感光層の場合は、これらを溶解させる溶剤を選択することも必要である。
【００６２】
次に本発明において場合により添加される染料色素としては、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等のトリフェニルメタン染料、メチレンブルーなどのチアジン染料、キニザリン等のキノン染料およびシアニン染料やビリリウム塩、チアビリリウム塩、ベンゾビリリウム塩等が挙げられる。
【００６３】
また、アリールアミン系化合物と電荷移動錯体を形成する電子吸引性化合物としては、例えばクロラニル、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、２，４，７−トリニトロフルオレノン、２，４，５，７−テトラニトロフルオレノン、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；テトラシアノエチレン、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の電子吸引性化合物が挙げられる。
【００６４】
さらに、本発明の電子写真用感光体の感光層は、成膜性、可撓性、機械的強度を向上させるために、周知の可塑剤を含有していてもよい。具体的には、フタル酸エステル、りん酸エステル、エポキシ化合物、塩素化パラフィン、塩素化脂肪酸エステル、メチルナフタレンのような芳香族化合物等が挙げられる。
【００６５】
上記した種々の添加剤のほか、積層型感光層の場合の電荷発生層は、必要に応じて、塗布性を改善するためのレベリング剤、酸化防止剤、増感剤等の各種添加剤を含んでいてもよい。更にまた電荷発生層は上記電荷発生材料の蒸着膜であってもよい。電荷発生層の膜厚は、通常０．０５〜５μｍ、好ましくは０．１〜２μｍ、より好ましくは０．１５〜０．８μｍが好適である。
【００６６】
積層型感光層の場合の電荷輸送層は、必要に応じて、酸化防止剤、増感剤等の各種添加剤並びに他の電荷輸送材料、例えば有機光伝導体として優れた性能を有する公知の他のアリールアミン化合物、ヒドラゾン化合物、スチルベン化合物を含んでいてもよい。電荷輸送層にはこの他に、塗膜の機械的強度や、耐久性向上のための種々の添加剤を用いることができる。この様な添加剤としては、前述の可塑剤のほか、種々の安定剤、流動性付与剤、架橋剤等が挙げられる。電荷輸送層の膜厚は、通常１０〜６０μｍ、好ましくは１０〜４５μｍ、より好ましくは２７〜４０μｍが好適である。
【００６７】
分散型感光層の場合にも、成膜性、可とう性、機械的強度等を改良するための前述の可塑剤のほか、残留電位を抑制するための添加剤、分散安定性向上のための分散補助剤、塗布性を改善するためのレベリング剤、界面活性剤、例えばシリコーンオイル、フッ素系オイルその他の添加剤が添加されていてもよい。分散型感光層の膜厚は、通常５〜５０μｍ、好ましくは１０〜４５μｍが好適である。
【００６８】
分散型感光層の場合、電荷発生材料の粒子径は充分小さいことが必要であり、好ましくは１μｍ以下、より好ましくは０．５μｍ以下で使用される。感光層内に分散される電荷発生材料の量は、例えば０．５〜５０重量％の範囲であるが、少なすぎると充分な感度が得られず、多すぎると帯電性の低下、感度の低下などの弊害があり、より好ましくは１〜２０重量％の範囲で使用される。
【００６９】
本発明において、所定の感光層を形成するための塗布方法としては、スプレー塗布法、スパイラル塗布法、リング塗布法、浸漬塗布法等がある。
スプレー塗布法としては、エアスプレー、エアレススプレー、静電エアスプレー、静電エアレススプレー、回転霧化式静電スプレー、ホットスプレー、ホットエアレススプレー等があるが、均一な膜厚を得るための微粒化度、付着効率等を考えると回転霧化式静電スプレーにおいて、再公表平１−８０５１９８号公報に開示されている搬送方法、すなわち円筒状ワークを回転させながらその軸方向に間隔を開けることなく連続して搬送することにより、総合的に高い付着効率で膜厚の均一性に優れた電子写真感光体を得ることができる。
【００７０】
スパイラル塗布法としては、特開昭５２−１１９６５１号公報に開示されている注液塗布機またはカーテン塗布機を用いた方法、特開平１−２３１９６６号公報に開示されている微小開口部から塗料を筋状に連続して飛翔させる方法、特開平３−１９３１６１号公報に開示されているマルチノズル体を用いた方法等がある。
【００７１】
浸漬塗布法においては、あらかじめ浸漬用に調整された塗布液を用いる。すなわち、感光体、バインダー樹脂等の全固形分濃度が、２５％以上、より好ましくは４０％以下、また、粘度が、通常５０〜３００センチポアーズ、好ましくは１００〜２００センチポアーズとなるように、塗布液を調整する。ここで、塗布液の粘度は、実質的にバインダー樹脂の種類およびその分子量により決まるが、あまり分子量が低いと樹脂自身の機械的強度が低下するので、これを損わない程度の分子量を持つバインダー樹脂を使用することが好ましい。
【００７２】
その後塗膜を乾燥させ、必要且つ充分な乾燥が行われる様に、乾燥温度時間を調整するとよい。乾燥温度は、通常１００〜２５０℃、好ましくは１１０〜１７０℃、さらに好ましくは１２０〜１４０℃の範囲である。乾燥方法としては、熱風乾燥機、蒸気乾燥機、赤外線乾燥機および遠赤外線乾燥機等を用いることができる。
【００７３】
このようにして形成される感光体は、電気特性・機械特性の改良のために、必要に応じ、感光層間または感光層と支持体の間に、バリアー層、接着層、ブロッキング層等の中間層を有していてもよく、また、感光層の表面に、保護層等の表面層を有していてもよいことはいうまでもない。
【００７４】
中間層としては、例えばアルミニウム陽極酸化被膜、酸化アルミニウム、水酸化アルミニウム等の無機層、ポリビニルアルコール、カゼイン、ポリビニルピロリドン、ポリアクリル酸、セルロース類、ゼラチン、デンプン、ポリウレタン、ポリイミド、ポリアミド等の有機層が使用される。また、表面層としては、例えば紫外線硬化樹脂等の保護層が使用される。
【００７５】
感光層が形成される導電性支持体としては、電子写真感光体に採用されているものがいずれも使用できる。具体的には、アルミニウム、ステンレス鋼、銅、ニッケル等の金属材料からなるドラム、シートあるいはこれらの金属箔のラミネート物；蒸着等により、表面にアルミニウム、銅、パラジウム、酸化スズ、酸化インジウム等の導電性層を設けたポリエステルフィルム、紙等の絶縁性支持体；金属粉末、カーボンブラック、ヨウ化銅、高分子電解質等の導電性物質を適当なバインダーとともに塗布して導電処理したプラスチックフィルム、プラスチックドラム、紙、紙管等；金属粉末、カーボンブラック、炭素繊維等の導電性物質を含有し、導電性となったプラスチックのシートやドラム；酸化スズ、酸化インジウム等の導電性金属酸化物で導電処理したプラスチックフィルムやベルトが挙げられる。なかでも、アルミニウム等の金属ドラムが好ましい支持体である。
【００７６】
以下、本発明を、実施例によってさらに詳細に説明する。
（製造例）
カルボニル導入反応
下記式で示されるアリールアミン化合物
【００７７】
【化２５】

【００７８】
２８．５ｇを、ＤＭＦ２５０ｍＬに溶解させた。６０℃まで昇温させ、オキシ塩化リン２３ｇを滴下した（６５℃±５℃）。２時間６５℃±５℃で反応させ、ＴＬＣにて反応終了確認後、放冷し、反応溶液を 水酸化カリウム水溶液（ＫＯＨ５０ｇ／水１ｋｇ）中に放出した。一昼夜放置後、析出した固体を濾別し、１Ｌの水で２回懸洗した（濾液が中性であることを確認）。減圧下、６０℃で３０時間乾燥させ、ＤＭＦ２００ｍｌに溶解させた。水１Ｌに放出し、析出した固体を濾別し、減圧下、６０℃で３０時間乾燥し、下記式で示されるホルミル体、暗黄色固体２６ｇを得た。
【００７９】
【化２６】

【００８０】
Ｗｉｔｔｉｇ反応
上記ホルミル体６．８ｇおよび下記式で示されるＷｉｔｔｉｇ試薬
【００８１】
【化２７】

【００８２】
９．１ｇをＴＨＦ７０ｍＬに溶解させ、ナトリウムメトキシドのメタノール２８％溶液５．８ｇを少しずつ添加した（２０℃±５℃）。１時間撹拌し、反応物をメタノール３００ｍＬに放出し、析出した固体を濾別した。固体を減圧下６０℃で乾燥させ、カラムにより精製し、前述の代表例として最初に挙げられた構造式で示され、３番目の置換基Ｘ１、Ｘ２を有する化合物５．４ｇを得た。その赤外線スペクトルを図１に示した。
【００８３】
（実施例１）
電荷発生層の形成
Ｘ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）９．３°、１０．６°、１３．２°、１５．１°、１５．７°、１６．１°、２０．８°、２３．３°、２６．２°、２７．１°に強い回折ピークを示すチタニウムオキシフタロシアニン顔料１．０部を、ジメトキシエタン１４部に加え、サンドグラインダーで分散処理をした後、ジメトキシエタン１４部と４−メトキシ−４−メチルペンタノン−２（三菱化学（株）社製）１４部を加え希釈し、さらに、ポリビニルブチラール（電気化学工業（株）社製、商品名デンカブチラール＃６０００−Ｃ）０．５部と、フェノキシ樹脂（ユニオンカーバイド（株）社製、商品名ＵＣＡＲ（商標登録）ＰＫＨＨ）０．５部をジメトキシエタン６部、４−メトキシ−４−メチルペンタノン−２ ６部の混合溶媒に溶解した液と混合し、分散液を得た。
この分散液を、７５μｍ膜厚のポリエステルフィルムに蒸着されたアミノ蒸着層の上に、乾燥後の重量が０．４ｇ／ｍ^２ になる様に、ワイヤーバーで塗布した後、乾燥して電荷発生層を形成させた。
【００８４】
電荷輸送層の形成
このようにして形成された電荷発生層の上に、前記製造例で合成したアリールアミン系化合物（前述の代表例として最初に挙げられた構造式で示され、３番目の置換基Ｘ１、Ｘ２を有する化合物）７０部と、下記式で示されるポリカーボネート樹脂
【００８５】
【化２８】

【００８６】
１００部を、テトラヒドロフランを主とする混合溶媒９００部に溶解した塗布液を塗布、乾燥し、膜厚２０μｍの電荷輸送層を形成させ、２層からなる感光層を有する、いわゆる積層型の電子写真用感光体を得た。
【００８７】
感光体の評価
このようにして得た電子写真用感光体について、下記の電気特性を測定した。
（１）感度すなわち半減露光量：
半減露光量はまず、感光体を暗所で５０μＡのコロナ電流により負帯電させ、次いで２０ルックスの白色光を干渉フィルターに通して得られた７８０ｎｍの光（露光エネルギー１０μＷ／ｃｍ^２ ）で露光し、表面電位が−５５０Ｖから−２７５Ｖまで減衰するのに要する露光量を測定することにより求めた。測定値は０．４８μＪ／ｃｍ^２ であった。
（２）残留電位：
さらに、露光時間を９．９秒とした時の表面電位を残留電位として測定したところ、−２１Ｖであった。この操作を２０００回繰り返したが、残留電位の上昇はみられなかった。
（３）ホール移動度：
ＴＯＦ法により、この感光体の電荷輸送層のホール移動度を調べたところ、図２に示す結果が得られた。図中、横軸は電界強度の平方根を示し、縦軸は移動度を示す。
【００８８】
（比較例１）
実施例１で用いたアリールアミン系化合物の代わりに、下記式で示される比較化合物１
【００８９】
【化２９】

【００９０】
を用いる以外は、実施例１と同様にして電子写真感光体を得た。次いで、実施例１と同様にして感度、残留電位、移動度を測定した。その結果を、実施例１の感光体についての測定結果とともに、表１および図２に示す。
【００９１】
（比較例２）
実施例１で用いたアリールアミン系化合物の代わりに、下記式で示される比較化合物２
【００９２】
【化３０】

【００９３】
を用いる以外は、実施例１と同様にして電子写真感光体を得ようとしたが、ポリマー液に溶解した後、塗布したところ、溶媒乾燥中に塗布面上で固体が析出し電気特性の測定はできなかった。
【００９４】

【００９５】
従って、実施例１のアリールアミン系化合物は、比較例１の電荷輸送化合物に比べ、電気特性、特に、感度、残留電位、移動度に優れており、比較例２に比べ、ポリマーとの相溶性に優れていることがわかる。
【００９６】
【発明の効果】
本発明の電子写真感光体は、ポリマーとの相溶性が高く、かつ、かぶりの原因となる残留電位が小さく、とくに光疲労が少ないために繰返し使用による残留電位の蓄積や、表面電位および感度の変動が小さく耐久性に優れるという特徴を有する。
【図面の簡単な説明】
【図１】製造例で得られたアリールアミン誘導体の赤外吸収スペクトル図。
【図２】実施例１および比較例１の感光体についての電荷輸送層のホール移動度対比図。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photoconductor for electrophotography. More specifically, the present invention relates to a very sensitive and high-performance electrophotographic photosensitive member having a photosensitive layer containing an organic photoconductive substance.
[0002]
[Prior art]
Conventionally, inorganic photoconductive substances such as selenium, cadmium sulfide, and zinc oxide have been widely used for a photosensitive layer of an electrophotographic photosensitive member. However, selenium and cadmium sulfide need to be recovered as poisons, and selenium crystallizes due to heat and therefore has poor heat resistance, cadmium sulfide and zinc oxide have poor moisture resistance, and zinc oxide has no printing durability. It has drawbacks, and efforts are being made to develop new photoreceptors. Recently, studies have been made on the use of organic photoconductive materials for the photosensitive layer of an electrophotographic photoreceptor, and some of them have been put to practical use. Organic photoconductive materials are lighter, easier to form films, easier to produce photoconductors, can produce transparent photoconductors depending on the type, and have no material compared to inorganic ones. It has advantages such as pollution.
[0003]
Recently, the so-called function-separated type photoreceptor, in which the charge carrier generation and transfer functions are shared by different compounds, is effective in increasing the sensitivity, and has become the mainstream of development. Practical use of photoreceptors is also being carried out.
As the charge carrier transport medium, there are a case where a polymer photoconductive compound such as polyvinyl carbazole is used and a case where a low molecular weight photoconductive compound is dispersed and dissolved in a binder polymer.
[0004]
[Problems to be solved by the invention]
In particular, organic low-molecular-weight photoconductive compounds can select polymers with excellent film properties, flexibility, adhesiveness, etc. as binders, making it easy to obtain photoconductors with excellent mechanical properties. (For example, JP-A-60-196767, JP-A-60-218652, JP-A-60-233156, JP-A-63-48552, JP-A-1-267552, Japanese Unexamined Patent Publication No. Hei 3-39306, Japanese Unexamined Patent Application Publication No. 3-113559, Japanese Unexamined Patent Application Publication No. 3-123358, Japanese Unexamined Patent Application Publication No. 3-149560, Japanese Unexamined Patent Application Publication No. 6-273950, Japanese Unexamined Patent Application Publication No. 62-36674, Japanese Unexamined Patent Application Publication No. 7-036203, JP-A-6-11854, JP-A-63-48553, etc.). However, it has been difficult to find a compound suitable for producing a highly sensitive photoreceptor.
[0005]
Furthermore, in the demand for continuous high sensitivity, various problems such as insufficient residual potential in terms of electrical characteristics, poor light responsiveness, deterioration of chargeability when repeatedly used, and accumulation of residual potential are caused. In order to solve such a problem, for example, a technique of using two specific hydrazone compounds in combination to prevent a rise in residual potential without significantly impairing other characteristics of the photoreceptor (Japanese Patent Application Laid-Open No. 61-134767). Etc. have been reported. However, the balance of the characteristics is not always sufficient, and a technique for improving the characteristics of the entire photoreceptor in a well-balanced manner has been required.
[0006]
Further, the compound group used in JP-A-9-244278 has extremely excellent properties as a charge transporting material, but has a slightly rigid solubility in a coating solvent due to a rigid skeleton. Although it was possible, there was a problem that it took time to complete dissolution.
[0007]
Furthermore, semiconductor lasers have been actively applied as light sources in the field of printers. In this case, since the wavelength of the light source is around 800 nm, a photosensitive material having high sensitivity to long wavelength light around 800 nm is used. Development of the body is strongly desired.
Materials suitable for this purpose include JP-A-59-49544, JP-A-59-214034, JP-A-61-109056, JP-A-61-171771, and JP-A-61-217050. JP, JP-A-61-239248, JP-A-62-67094, JP-A-62-134651, JP-A-62-275272, JP-A-63-198067, Examples include materials described in JP-A-63-198068, JP-A-63-210942, JP-A-63-218768, and the like. Oxytitanium having a crystal type suitable for a material for an electrophotographic photosensitive member is used. Various phthalocyanines are known. However, there has been a demand for an electrophotographic photoreceptor having high sensitivity to long-wavelength light and excellent other electrical characteristics.
[0008]
The present invention has been made to solve the above-described problems, and a first object of the present invention is to provide an electrophotographic photosensitive member having high sensitivity and high durability.
A second object is an electrophotographic photoreceptor which has high sensitivity, has a sufficiently low residual potential even when the film thickness is increased, has little variation in characteristics even when used repeatedly, and has extremely excellent durability. Is to provide.
A third object of the present invention is to provide a photoreceptor for electrophotography, which has high sensitivity even at a long wavelength of about 800 nm and has good balance in chargeability, dark decay, residual potential, and the like.
A fourth object of the present invention is to provide a photosensitive member having good responsiveness and high carrier mobility.
[0009]
[Means for Solving the Problems]
The present inventors have conducted intensive studies on organic low-molecular-weight photoconductive compounds that can satisfy these objects, and have found that a specific arylamine-based compound is suitable, and have reached the present invention. That is, the gist of the present invention resides in an electrophotographic photosensitive member having a photosensitive layer containing an arylamine-based compound represented by the following general formula [1] on a conductive support.
[0010]
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[0011]
(In the above general formula [1], A, B, C, D, E and F represent a benzene ring which may have a substituent, and these may be bonded to each other to form a heterocyclic ring; Y represents a divalent aliphatic hydrocarbon residue which may have a substituent;
X¹  And X²  Represents a group represented by the following general formulas [2] and [3], which may be the same or different. )
[0012]
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[0013]
(In the above general formulas [2] and [3], n₃  Represents an integer of 1 to 4; n₄  Represents an integer from 1 to 4;⁵  , R⁶  , R⁷  , R⁸  , R⁹  , R¹⁰, R¹¹, R¹², R^ThirteenAnd R¹⁴Represents a hydrogen atom, a cyano group, a nitro group, an alkyl group which may have a substituent, an aryl group which may have a substituent, or a heterocyclic group which may have a substituent. May be the same or different from each other, and R⁸  And R⁹  A pair consisting of and R^ThirteenAnd R¹⁴May be condensed to form a carbocyclic group or a heterocyclic group, and when one of R in these pairs is a hydrogen atom, the other is an aryl group or a heterocyclic group. It is. )
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
The electrophotographic photoreceptor of the present invention contains the arylamine-based compound represented by the general formula [1] in the photosensitive layer.
[0015]
In the general formula [1], A, B, C, D, E, and F each represent a benzene ring, which are bonded to each other to form a bond between any two of A, B, and C; , E, or F,
A heterocyclic ring containing a nitrogen atom via a single bond, a methylene group, an ethylene group, a carbonyl group, a vinylidene group, an ethylenylene group, etc. may be formed, and if desired, further contain an oxygen atom, a sulfur atom, a nitrogen atom, etc. , May form a heterocyclic ring.
[0016]
These benzene rings may have a substituent, as a substituent,
Hydroxyl group;
Halogen atoms such as fluorine, chlorine, bromine and iodine;
Alkyl groups such as methyl group, ethyl group, propyl group, butyl group, hexyl group and isopropyl group;
Alkoxy groups such as methoxy, ethoxy and propyloxy groups;
Alkenyl groups such as allyl group, vinyl group and butenyl group;
Aralkyl groups such as benzyl group, naphthylmethyl group, phenethyl group;
An aryloxy group such as a phenoxy group and a toloxy group;
Arylalkoxy groups such as benzyloxy group and phenethyloxy group;
Aryl groups such as phenyl and naphthyl;
Acyl groups such as acetyl and benzoyl;
Dimethylamino group, dialkylamino group such as diethylamino group,
Diphenylamino group, diarylamino group such as dinaphthylamino group,
Dibenzylamino group, diaralkylamino group such as diphenethylamino group,
Dipyridylamino group, diheterocyclic amino group such as dithienylamino group,
A disubstituted amino group such as a diallylamino group, or a substituted amino group such as a disubstituted amino group or a monosubstituted amino group in which one of the substituents of these disubstituted amino groups is replaced with another substituent or a hydrogen atom can give.
The substituents on each benzene ring may be singular or plural, and in the case of plural, they may be the same or different from each other.Moreover, these substituents are condensed with each other to form on each benzene ring Between different positions of
A carbon ring may be formed via a single bond, a methylene group, an ethylene group, a carbonyl group, a vinylidene group, an ethylenylene group, or the like.If desired, a heterocyclic group containing an oxygen atom, a sulfur atom, a nitrogen atom, or the like may be used. It may be formed.
[0017]
In the general formula [1], Y is a divalent residue obtained by removing two hydrogen atoms from an aliphatic hydrocarbon such as methane, ethane, propane, cyclohexane, and cyclopentane. Examples thereof include a methylene group, an ethylene group, a propylene group, and a cyclohexylidene group. The position excluding a hydrogen atom may be any of the same or different carbon atoms among carbon atoms constituting a hydrocarbon. The aliphatic hydrocarbon residue is particularly preferably an alicyclic hydrocarbon residue, for example, a cyclohexylidene group.
[0018]
These divalent residues may have a substituent on the carbon ring or carbon chain, and the substituent may be singular or plural, and in the case of plural, they may be the same or different from each other In addition, these substituents may be fused together to form a carbocyclic or heterocyclic ring between different positions on each ring or chain or with another ring or chain. Further, those condensed rings may have a substituent.
As the substituent of the divalent residue or the condensed ring,
Alkyl groups such as methyl group, ethyl group, propyl group, butyl group, hexyl group and isopropyl group;
Aryl groups such as phenyl and naphthyl;
A cyano group;
An alkoxycarbonyl group;
An aryloxycarbonyl group;
Nitro group;
Examples thereof include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
[0019]
In the general formula [1], X¹  Represents a group represented by the following general formula [2],
X²  Represents a group represented by the following general formula [3], which may be the same or different.
[0020]
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[0021]
In the general formulas [2] and [3], n₃  Represents an integer of 1 to 4; n₄  Represents an integer of 1 to 4. n₃  And n₄  Is preferably 1 or 2 from the viewpoint of solubility.
[0022]
Also, R⁵  , R⁶  , R⁷  , R⁸  , R⁹  , R¹⁰, R¹¹, R¹², R^ThirteenAnd R¹⁴Is
A hydrogen atom; a cyano group; a nitro group;
An alkyl group such as a methyl group, an ethyl group, a propyl group or an isopropyl group;
Aryl groups such as phenyl, naphthyl and pyrenyl;
Represents a heterocyclic group such as a pyridyl group and a thienyl group,
These may be the same or different from each other,
Particularly, a hydrogen atom, a methyl group and a phenyl group are preferable.
[0023]
These alkyl group, aryl group, heterocyclic group may have a substituent,
As the substituent,
Hydroxyl group;
Halogen atoms such as fluorine, chlorine, bromine and iodine;
Alkyl groups such as methyl group, ethyl group, propyl group, butyl group, hexyl group and isopropyl group;
Alkoxy groups such as methoxy, ethoxy and propyloxy groups;
Alkenyl groups such as allyl group, vinyl group and butenyl group;
Aralkyl groups such as benzyl group, naphthylmethyl group, phenethyl group;
An aryloxy group such as a phenoxy group and a toloxy group;
Arylalkoxy groups such as benzyloxy group and phenethyloxy group;
Aryl groups such as phenyl and naphthyl;
Arylvinyl groups such as styryl groups and naphthylvinyl groups;
Acyl groups such as acetyl and benzoyl;
Dimethylamino group, dialkylamino group such as diethylamino group,
Diphenylamino group, diarylamino group such as dinaphthylamino group,
Dibenzylamino group, diaralkylamino group such as diphenethylamino group,
Dipyridylamino group, diheterocyclic amino group such as dithienylamino group,
A disubstituted amino group such as a diallylamino group, or a substituted amino group such as a disubstituted amino group or a monosubstituted amino group in which one of the substituents of these disubstituted amino groups is replaced with another substituent or a hydrogen atom can give.
The above-mentioned various substituents contained in the alkyl group, the aryl group and the heterocyclic group may be singular or plural, and in the case of plural, these substituents are condensed with each other to form the same R⁵  , R⁶  , R⁷  , R⁸  , R⁹  , R¹⁰, R¹¹, R¹², R^ThirteenOr R¹⁴Within a different R⁵  , R⁶  In between, different R¹⁰, R¹¹In between, R⁷  And R⁵  , R⁶  Between or R¹²And R¹⁰, R¹¹Between
A carbon ring may be formed via a single bond, a methylene group, an ethylene group, a carbonyl group, a vinylidene group, an ethylenylene group, or the like.If desired, a heterocyclic ring containing an oxygen atom, a sulfur atom, a nitrogen atom, or the like may be formed. May be.
Where R⁸  And R⁹  A pair consisting of and R^ThirteenAnd R¹⁴May be condensed to form a carbocyclic group or a heterocyclic group, and when one of R in these pairs is a hydrogen atom, the other is an aryl group or a heterocyclic group. It is.
[0024]
Hereinafter, typical examples of the arylamine-based compound represented by the general formula [1] will be listed for illustrative purposes. Of course, the arylamine-based compound used in the present invention is not limited to only these representative examples. In the following examples, following the general formula [1], the structural formula of the compound and the substituents X1 and X2 are displayed separately. Represents only the substituents X1 and X2.
[0025]
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[0026]
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[0027]
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[0028]
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[0029]
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[0030]
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[0031]
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[0032]
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[0033]
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[0034]
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[0035]
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[0036]
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[0037]
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[0038]
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[0039]
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[0040]
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[0041]
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[0042]
The arylamine-based compound represented by the general formula [1] can be produced by a known method. For example, a known carbonyl introduction reaction is performed using a known arylamine-based compound as a raw material, and then a Wittig reaction is performed to obtain a target compound.
To explain this method in detail, first, the carbonyl introduction reaction is represented by the following reaction formula.
[0043]
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[0044]
In the above reaction formula showing the carbonyl introduction reaction and the reaction formula showing the Wittig reaction described below, the ring A, B, C, D, E and F, the group R⁵  , R⁶  , R⁷  , R⁸  , R⁹  , R¹⁰, R¹¹, R¹², R^Thirteen, R¹⁴, Y, X¹And X²And subscript n₃And n₄ Has the same meaning as in general formulas [1], [2] and [3] above.
[0045]
1) R⁵  = R¹⁰= H:
When the arylamine-based compound represented by the general formula [4] is reacted with a formylating agent such as N, N-dimethylformamide or N-methylformanilide in the presence of phosphorus oxychloride, the general formula [5] is obtained. The aldehyde form shown is obtained. At this time, a large excess of the formylating agent can be used as a reaction solvent, but an inert solvent such as O-dichlorobenzene or benzene can also be used.
[0046]
2) R⁵  , R¹⁰≠ H
The arylamine-based compound represented by the general formula [4] is prepared by subjecting an arylamine-based compound represented by the general formula Cl-CO-R in a solvent such as nitrobenzene, dichloromethane, carbon tetrachloride or the like in the presence of a Lewis acid such as aluminum chloride, iron chloride or zinc chloride.⁵  And an acid chloride represented by the general formula Cl-CO-R¹⁰By reacting with an acid chloride represented by the formula, a ketone compound represented by the general formula [5] is obtained.
[0047]
Then, the aldehyde or ketone represented by the general formula [5] obtained by the carbonyl introduction reaction is reacted with N, N-dimethylformamide, N, N-dimethylacetamide, tetrahydrofuran, dioxane, benzene, toluene or the like. In a known inert organic solvent, triphenylphosphine or triphenylphosphine is added to a halogen compound represented by the general formulas [6] and [6 '] (wherein Q represents a halogen atom such as a chlorine atom or a bromine atom). Trialkoxy phosphorus compounds (R^FifteenO)₃  P (R^FifteenRepresents an alkyl group such as a methyl group and an ethyl group. ) And a known base such as butyllithium, phenyllithium, sodium methoxide, sodium ethoxide and potassium t-butoxide at a temperature of 10 to 200 ° C, preferably 20 to 100 ° C. By reacting in the presence of a neutral catalyst, an arylamine-based compound represented by the general formula [1] is obtained.
This Wittig reaction is represented by the following reaction formula.
[0048]
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[0049]
At this time, as the arylamine-based compound represented by the general formula [1], any one of a cis-form, a trans-form, and a mixture of the cis-form and the trans-form is obtained.
In these reactions, in some cases, after completion of each step or after completion of all the steps, it is possible to obtain a high-purity compound by a known purification means such as recrystallization purification, reprecipitation purification, sublimation purification, and column purification. .
[0050]
The electrophotographic photoreceptor of the present invention has, on a conductive support, a photosensitive layer (photoconductive layer) containing one or more kinds of the arylamine-based compound represented by the general formula [1]. Thus, the arylamine-based compound represented by the general formula [1] exhibits extremely excellent performance as an organic photoconductor. In particular, when used as a charge transport medium, a photosensitive member having high sensitivity and excellent durability is provided.
[0051]
In the electrophotographic photoreceptor of the present invention, the photosensitive layer can take any form as long as the photosensitive layer contains the arylamine-based compound represented by the general formula [1]. That is, the photosensitive layer comprises a charge generation layer containing a charge generation material that generates charge carriers with extremely high efficiency when absorbing light, and a charge transport layer containing a charge transport material that transports charge carriers, in this order or vice versa. A so-called lamination type in which layers are sequentially formed, or a so-called dispersion type in which a layer in which particles of a charge generation material are dispersed in a dispersion medium containing a charge transport material may be formed.
[0052]
In the present invention, when the arylamine-based compound represented by the general formula [1] is used in a charge transport layer of a laminated photosensitive layer including a charge generation layer and a charge transport layer, the sensitivity is particularly high. Thus, a photosensitive member having high durability, a small residual potential, and little variation in surface potential, a decrease in sensitivity, accumulation of the residual potential, etc., when used repeatedly, and having excellent durability can be obtained.
[0053]
The charge generation material used in the electrophotographic photoreceptor of the present invention is not particularly limited, and inorganic photoconductive particles such as selenium, selenium-tellurium alloy, selenium-arsenic alloy, cadmium sulfide, and amorphous silicon; metal-free phthalocyanine; Organic photoconductive particles such as metal-containing phthalocyanine, perinone pigments, thioindigo, quinacridone, perylene pigments, anthraquinone pigments, monoazo pigments, bisazo pigments, trisazo pigments, polyazo pigments, and cyanine pigments. Further, various organic dyes such as polycyclic quinone, pyrylium salt, thiopyrylium salt, indigo, anthantrone and pyranthrone can also be used.
[0054]
Among these charge generation materials, metal-free phthalocyanines; metals such as copper, indium chloride, gallium chloride, tin, oxytitanium, zinc, and vanadium or oxides thereof, and metal-containing phthalocyanines coordinated with chloride; monoazo, bisazo And azo pigments such as trisazo and polyazo are preferred.
[0055]
Among them, a metal-containing phthalocyanine and a metal-free phthalocyanine are preferable when combined with the arylamine-based compound represented by the general formula [1], since a photoconductor having improved sensitivity to laser light can be obtained.
In particular, a) oxytitanium phthalocyanine exhibiting diffraction peaks at 9.7 °, 14.2 ° and 27.3 ° in the Bragg angles (2θ ± 0.2 °) of the X-ray diffraction spectrum, and b) Bragg of the X-ray diffraction spectrum Oxytitanium phthalocyanine or c) exhibiting diffraction peaks at angles (2θ ± 0.2 °) of 9.3 °, 13.2 °, 26.2 ° and 27.1 °) Bragg angle (2θ ± 0) of X-ray diffraction spectrum 0.3%) An electrophotographic photoreceptor containing a dihydroxysilicon phthalocyanine compound having diffraction peaks at 9.2 °, 14.1 °, 15.3 °, 19.7 ° and 27.1 ° has high sensitivity, Since the residual potential is low, the chargeability is high, the fluctuation due to repetition is small, and particularly the charge stability affecting the image density is good, it can be used as a highly durable photoreceptor. Further, since the sensitivity is high in the range of 750 to 850 nm, it is particularly suitable for a photoconductor for a semiconductor laser printer.
[0056]
The method for producing the oxytitanium phthalocyanine of the above a) is not particularly limited, but is produced, for example, by the following method.
1 A method for producing [II] type crystals described in Production Example 1 of JP-A-62-67094. That is, orthophthalodinitrile and a halide of titanium are heated and reacted in an inert organic solvent, and then hydrolyzed.
2 Oxytitanium phthalocyanine of various crystal types was converted to sulfuric acid or a compound of the formula R-SO directly or in an organic acid solvent.₃  H (wherein R represents an aliphatic or aromatic residue which may have a substituent), or heat-treated with a sulfonate represented by the formula (I), And heating with a mixed solvent.
3 If desired, dissolve in concentrated sulfuric acid in advance and release it into ice water, or make it amorphous by a known method such as a mechanical grinding method such as a paint shaker, a ball mill, or a sand grind mill, and then heat-treat with the above sulfonated product. And heat treatment with a mixed solvent of water-insoluble organic solvent and water.
4. In the case of the treatment with the above-mentioned sulfonated product, a mechanical grinding method such as a paint shaker, a ball mill, and a sand grind mill is used in place of the heat treatment.
[0057]
In the present invention, two or more phthalocyanine compounds can be used in combination as the charge generating material. For example, the oxytitanium phthalocyanine which exhibits diffraction peaks at 9.7 °, 14.2 °, and 27.3 ° with the Bragg angle (2θ ± 0.2 °) of the above X-ray diffraction spectrum and the Bragg angle of the X-ray diffraction spectrum ( 2θ ± 0.2 °) Combined use with oxytitanium phthalocyanine showing diffraction peaks at 9.3 °, 13.2 °, 26.2 ° and 27.1 °, or the Bragg angle of the X-ray diffraction spectrum described above (2θ ± 0.2 °) Oxytitanium phthalocyanine exhibiting diffraction peaks at 9.7 °, 14.2 ° and 27.3 ° and the Bragg angle (2θ ± 0.2 °) of X-ray diffraction spectrum 8.5 ° , 12.2 °, 13.8 °, 16.9 °, 22.4 °, 28.4 ° and 30.1 ° are preferably used in combination with dichlorotin phthalocyanine showing diffraction peaks at the point of sensitivity. .
[0058]
The electrophotographic photoreceptor of the present invention can be manufactured according to a conventional method. That is, the above-described charge generating material and / or charge transporting material are dissolved in a suitable solvent together with a binder, and if necessary, a known sensitizing dye, an electron-withdrawing compound, a plasticizer, and other known additives are added. The coating solution obtained as described above can be produced by applying the coating solution on a conductive support, drying it, and forming a photosensitive layer having a predetermined thickness. In the case of a laminated photosensitive layer composed of a charge generating layer and a charge transporting layer, it is necessary to prepare the charge generating material and the charge transporting material as separate coating liquids, respectively, and apply them sequentially. In this case, it is only necessary to apply a coating solution containing both materials. Needless to say, the charge generation layer of the laminated photosensitive layer can be formed not by coating but by vapor deposition.
[0059]
As the binder resin used for the charge generation layer in the laminated photosensitive layer, for example, polyester resin, polyvinyl acetate, polyester polycarbonate, polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, phenoxy resin, epoxy resin, urethane resin, cellulose ester, Cellulose ether and the like can be mentioned. There is no limitation as long as fine particles such as a charge generation material can be formed into a dispersion layer in a form bound with various binder resins. In addition to these, binder resins such as polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylates, methacrylates, vinyl alcohol, and ethyl vinyl ether, polyamides, and silicon resins can also be used. . In this case, the usage ratio of the charge generating material is selected from the range of usually 20 to 2,000 parts by weight, preferably 30 to 500 parts by weight, more preferably 33 to 500 parts by weight with respect to 100 parts by weight of the binder resin.
[0060]
The binder resin used for the charge transport layer in the case of the laminated type photosensitive layer or the binder resin used as the matrix in the case of the dispersed type photosensitive layer has good compatibility with the charge transport material, Polymers in which the transport material does not crystallize or undergo phase separation are preferred, for example, polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylates, methacrylates, butadiene, and polyvinyl acetal. , Various polymers such as polycarbonate, polyester, polyester carbonate, polysulfone, polyimide, polyphenylene oxide, polyurethane, cellulose ester, cellulose ether, phenoxy resin, silicon resin and epoxy resin, and partially cross-linked cured products thereof. You can use. The amount of the binder used is in the range of 0.5 to 30 times, preferably 0.7 to 10 times the weight of the charge transporting material.
[0061]
Examples of the solvent for preparing the coating liquid include ethers such as tetrahydrofuran, 1,4-dioxane, and dimethoxyethane; ketones such as methyl ethyl ketone, 4-methoxy-4-methylpentanone-2 and cyclohexanone; and aromatics such as toluene and xylene. Group hydrocarbons; aprotic polar solvents such as N, N-dimethylformamide, acetonitrile, N-methylpyrrolidone, dimethylsulfoxide; esters such as ethyl acetate, methyl formate, methyl cellosolve acetate; chlorinated carbonization such as dichloroethane and chloroform And hydrogens. Of course, it is necessary to select one that dissolves the binder from these. Further, in the case of a photosensitive layer containing a charge transporting material such as an arylamine-based compound, it is necessary to select a solvent in which these are dissolved.
[0062]
Next, in the present invention, dyes that are optionally added include, for example, triphenylmethane dyes such as methyl violet, brilliant green, and crystal violet, thiazine dyes such as methylene blue, quinone dyes such as quinizarin, and cyanine dyes and beryllium salts, and thiavirylium. Salts, benzovirylium salts and the like.
[0063]
Examples of the electron-withdrawing compound that forms a charge transfer complex with the arylamine-based compound include, for example, chloranil, 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 1-chloro-5-nitroanthraquinone, Quinones such as chloroanthraquinone and phenanthrenequinone; aldehydes such as 4-nitrobenzaldehyde; 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 2,4,7-trinitrofluorenone, and 2,4,5 Ketones such as 7,7-tetranitrofluorenone and 3,3 ', 5,5'-tetranitrobenzophenone; acid anhydrides such as phthalic anhydride and 4-chloronaphthalic anhydride; tetracyanoethylene, terephthalalmalononitrile, 9-anthrylmethylidenemalononitrile, 4- Cyano compounds such as trobenzalmalononitrile and 4- (p-nitrobenzoyloxy) benzalmalonenitrile; 3-benzalphthalide, 3- (α-cyano-p-nitrobenzal) phthalide, 3- (α-cyano-p- And electron-withdrawing compounds such as phthalides such as (nitrobenzal) -4,5,6,7-tetrachlorophthalide.
[0064]
Further, the photosensitive layer of the electrophotographic photoreceptor of the present invention may contain a well-known plasticizer in order to improve film forming property, flexibility, and mechanical strength. Specific examples include phthalic acid esters, phosphoric acid esters, epoxy compounds, chlorinated paraffins, chlorinated fatty acid esters, and aromatic compounds such as methylnaphthalene.
[0065]
In addition to the various additives described above, the charge generating layer in the case of the laminated photosensitive layer contains various additives such as a leveling agent for improving coating properties, an antioxidant, and a sensitizer, if necessary. You may go out. Furthermore, the charge generation layer may be a deposited film of the above-described charge generation material. The thickness of the charge generation layer is generally 0.05 to 5 μm, preferably 0.1 to 2 μm, and more preferably 0.15 to 0.8 μm.
[0066]
The charge transport layer in the case of the laminated photosensitive layer may be, if necessary, various additives such as an antioxidant and a sensitizer and other charge transport materials, for example, other known materials having excellent performance as an organic photoconductor. May include an arylamine compound, a hydrazone compound, and a stilbene compound. In addition to the above, various additives for improving the mechanical strength and durability of the coating film can be used in the charge transport layer. Examples of such additives include various stabilizers, flowability-imparting agents, cross-linking agents, etc., in addition to the above-mentioned plasticizers. The film thickness of the charge transport layer is usually 10 to 60 μm, preferably 10 to 45 μm, and more preferably 27 to 40 μm.
[0067]
Also in the case of the dispersion type photosensitive layer, in addition to the above-mentioned plasticizer for improving film forming property, flexibility, mechanical strength, etc., an additive for suppressing residual potential, for improving dispersion stability. A dispersing aid, a leveling agent for improving applicability, and a surfactant such as silicone oil, fluorine-based oil and other additives may be added. The thickness of the dispersion type photosensitive layer is usually 5 to 50 μm, preferably 10 to 45 μm.
[0068]
In the case of a dispersion type photosensitive layer, the particle size of the charge generating material needs to be sufficiently small, and is preferably 1 μm or less, more preferably 0.5 μm or less. The amount of the charge generating material dispersed in the photosensitive layer is, for example, in the range of 0.5 to 50% by weight. If the amount is too small, sufficient sensitivity cannot be obtained. If the amount is too large, the chargeability and sensitivity decrease. And more preferably used in the range of 1 to 20% by weight.
[0069]
In the present invention, examples of a coating method for forming a predetermined photosensitive layer include a spray coating method, a spiral coating method, a ring coating method, and a dip coating method.
Spray coating methods include air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, hot airless spray, etc., but fine particles for obtaining a uniform film thickness In consideration of the degree of chemical conversion, adhesion efficiency, etc., in the case of a rotary atomizing electrostatic spray, the conveying method disclosed in Japanese Unexamined Patent Publication No. 1-805198, that is, the cylindrical workpiece is rotated and spaced apart in the axial direction. By continuously transporting the electrophotographic photoreceptors, it is possible to obtain an electrophotographic photoreceptor excellent in uniformity of film thickness with high overall adhesion efficiency.
[0070]
Examples of the spiral coating method include a method using a liquid coating machine or a curtain coating machine disclosed in JP-A-52-119651, and a method of coating a coating material through a fine opening disclosed in JP-A-1-231966. There is a method of continuously flying in a streak shape, a method using a multi-nozzle body disclosed in JP-A-3-193161, and the like.
[0071]
In the dip coating method, a coating liquid adjusted for dipping in advance is used. That is, the coating liquid is adjusted so that the total solid content of the photoreceptor and the binder resin is 25% or more, more preferably 40% or less, and the viscosity is usually 50 to 300 centipoise, preferably 100 to 200 centipoise. To adjust. Here, the viscosity of the coating solution is substantially determined by the type and molecular weight of the binder resin. However, if the molecular weight is too low, the mechanical strength of the resin itself decreases, so that the binder having a molecular weight that does not impair the mechanical strength of the resin itself. Preferably, a resin is used.
[0072]
Thereafter, the coating film is dried, and the drying temperature and time may be adjusted so that necessary and sufficient drying is performed. The drying temperature is usually in the range of 100 to 250 ° C, preferably 110 to 170 ° C, more preferably 120 to 140 ° C. As a drying method, a hot air dryer, a steam dryer, an infrared dryer, a far infrared dryer, or the like can be used.
[0073]
The photoreceptor thus formed may be provided with an intermediate layer such as a barrier layer, an adhesive layer, a blocking layer, etc., as necessary, in order to improve the electrical and mechanical properties. Needless to say, the photosensitive layer may have a surface layer such as a protective layer on the surface thereof.
[0074]
As the intermediate layer, for example, an anodized aluminum film, an inorganic layer such as aluminum oxide and aluminum hydroxide, and an organic layer such as polyvinyl alcohol, casein, polyvinylpyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide, and polyamide. Is used. Further, as the surface layer, for example, a protective layer such as an ultraviolet curable resin is used.
[0075]
As the conductive support on which the photosensitive layer is formed, any of those used for electrophotographic photosensitive members can be used. Specifically, drums, sheets or laminates of these metal foils made of a metal material such as aluminum, stainless steel, copper, nickel, etc .; aluminum, copper, palladium, tin oxide, indium oxide, etc. Insulating support such as polyester film or paper provided with conductive layer; plastic film or plastic which has been subjected to conductive treatment by applying a conductive material such as metal powder, carbon black, copper iodide, or polymer electrolyte together with a suitable binder Drums, paper, paper tubes, etc .; conductive plastic sheets and drums containing conductive materials such as metal powder, carbon black, and carbon fiber; conductive with conductive metal oxides such as tin oxide and indium oxide Treated plastic films and belts. Among them, a metal drum such as aluminum is a preferred support.
[0076]
Hereinafter, the present invention will be described in more detail with reference to Examples.
(Production example)
Carbonyl introduction reaction
Arylamine compound represented by the following formula
[0077]
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[0078]
28.5 g was dissolved in 250 mL of DMF. The temperature was raised to 60 ° C., and 23 g of phosphorus oxychloride was added dropwise (65 ° C. ± 5 ° C.). The reaction was carried out at 65 ° C. ± 5 ° C. for 2 hours. After confirming the completion of the reaction by TLC, the reaction solution was allowed to cool, and the reaction solution was discharged into an aqueous solution of potassium hydroxide (KOH 50 g / water 1 kg). After standing overnight, the precipitated solid was separated by filtration and washed twice with 1 L of water (confirmed that the filtrate was neutral). It was dried at 60 ° C. for 30 hours under reduced pressure, and dissolved in 200 ml of DMF. The solid was discharged into 1 L of water, and the deposited solid was separated by filtration and dried under reduced pressure at 60 ° C. for 30 hours to obtain a formyl compound represented by the following formula and 26 g of a dark yellow solid.
[0079]
Embedded image

[0080]
Wittig reaction
6.8 g of the above formyl compound and a Wittig reagent represented by the following formula
[0081]
Embedded image

[0082]
9.1 g was dissolved in 70 mL of THF, and 5.8 g of a 28% methanol solution of sodium methoxide was added little by little (20 ° C. ± 5 ° C.). After stirring for 1 hour, the reaction product was discharged into 300 mL of methanol, and the precipitated solid was separated by filtration. The solid was dried at 60 ° C. under reduced pressure and purified by a column to obtain 5.4 g of a compound represented by the structural formula first mentioned as a representative example and having the third substituents X1 and X2. The infrared spectrum is shown in FIG.
[0083]
(Example 1)
Formation of charge generation layer
In the X-ray diffraction spectrum, Bragg angles (2θ ± 0.2 °) 9.3 °, 10.6 °, 13.2 °, 15.1 °, 15.7 °, 16.1 °, 20.8 ° , 23.3 °, 26.2 °, 27.1 °, 1.0 part of a titanium oxyphthalocyanine pigment exhibiting strong diffraction peaks was added to 14 parts of dimethoxyethane, and after dispersion treatment with a sand grinder, dimethoxyethane 14 was added. And 14 parts of 4-methoxy-4-methylpentanone-2 (manufactured by Mitsubishi Chemical Corporation) were added and diluted, and then polyvinyl butyral (Denka Butyral # 6000-, manufactured by Denki Kagaku Kogyo Co., Ltd.) C) 0.5 part of a phenoxy resin (trade name: UCAR (registered trademark) PKHH, manufactured by Union Carbide Co., Ltd.) is mixed with 0.5 part of dimethoxyethane and 4-methoxy-4-methylpentanone-26. Part of It was mixed with a solution dissolved in a mixed solvent to obtain a dispersion.
This dispersion is applied on an amino vapor-deposited layer vapor-deposited on a 75 μm-thick polyester film to a weight of 0.4 g / m 2 after drying.²And then dried to form a charge generation layer.
[0084]
Formation of charge transport layer
On the charge generation layer thus formed, the arylamine-based compound synthesized in the above-mentioned Production Example (the first substituent represented by the structural formula given above as a representative example, the third substituent X1, X2 Compound) and a polycarbonate resin represented by the following formula:
[0085]
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[0086]
100 parts of a coating solution obtained by dissolving in 900 parts of a mixed solvent mainly composed of tetrahydrofuran is applied and dried to form a 20 μm-thick charge transporting layer, and a so-called laminated electrophotograph having a two-layer photosensitive layer. A photoreceptor was obtained.
[0087]
Photoconductor evaluation
The following electrical characteristics of the electrophotographic photoreceptor thus obtained were measured.
(1) Sensitivity, ie, half-exposure amount:
First, the photoreceptor was negatively charged in a dark place with a corona current of 50 μA, and then the light of 780 nm obtained by passing white light of 20 lux through an interference filter (exposure energy: 10 μW / cm)²), And the amount of exposure required for the surface potential to attenuate from -550 V to -275 V was determined. The measured value is 0.48 μJ / cm²Met.
(2) Residual potential:
Further, when the surface potential when the exposure time was set to 9.9 seconds was measured as a residual potential, it was -21 V. This operation was repeated 2000 times, but no increase in the residual potential was observed.
(3) Hall mobility:
When the hole mobility of the charge transport layer of this photoreceptor was examined by the TOF method, the result shown in FIG. 2 was obtained. In the figure, the horizontal axis indicates the square root of the electric field intensity, and the vertical axis indicates the mobility.
[0088]
(Comparative Example 1)
Comparative compound 1 represented by the following formula instead of the arylamine compound used in Example 1
[0089]
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[0090]
An electrophotographic photoreceptor was obtained in the same manner as in Example 1 except for using. Next, sensitivity, residual potential, and mobility were measured in the same manner as in Example 1. The results are shown in Table 1 and FIG. 2 together with the measurement results for the photoconductor of Example 1.
[0091]
(Comparative Example 2)
Comparative compound 2 represented by the following formula instead of the arylamine compound used in Example 1
[0092]
Embedded image

[0093]
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the polymer was used. However, when the polymer was dissolved in a polymer solution and applied, a solid precipitated on the coated surface during drying of the solvent, and the electrical characteristics were measured. Could not.
[0094]

[0095]
Therefore, the arylamine-based compound of Example 1 is superior to the charge transport compound of Comparative Example 1 in electrical properties, particularly, sensitivity, residual potential, and mobility, and is more compatible with the polymer than Comparative Example 2. It turns out that it is excellent.
[0096]
【The invention's effect】
The electrophotographic photoreceptor of the present invention has a high compatibility with a polymer, and has a small residual potential that causes fogging.In particular, accumulation of the residual potential due to repeated use due to little light fatigue, surface potential and sensitivity. It has the characteristic that the fluctuation is small and the durability is excellent.
[Brief description of the drawings]
FIG. 1 is an infrared absorption spectrum of an arylamine derivative obtained in Production Example.
FIG. 2 is a diagram showing hole mobility of a charge transport layer in the photoconductors of Example 1 and Comparative Example 1.

Claims (3)

An electrophotographic photoreceptor comprising a conductive support and a photosensitive layer containing an arylamine-based compound represented by the following general formula [1].

(In the above general formula [1],
A, B, C, D, E, and F represent an optionally substituted benzene ring, which may be bonded to each other to form a heterocyclic ring;
Y represents a divalent aliphatic hydrocarbon residue which may have a substituent;
X ¹ and X ² each represent a group represented by the following formulas [2] and [3], which may be the same or different. )

(In the above general formulas [2] and [3],
n ₃ represents an integer of 1 to 4;
n ₄ represents an integer of 1 to 4;
R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ may each have a hydrogen atom, a cyano group, a nitro group, or a substituent. An alkyl group, an aryl group which may have a substituent or a heterocyclic group which may have a substituent, which may be the same or different from each other,
The pair consisting of R ⁸ and R ⁹ and the pair consisting of R ¹³ and R ¹⁴ may be condensed to form a carbocyclic or heterocyclic group, and one of R of these pairs is hydrogen. When it is an atom, the other is an aryl group or a heterocyclic group. ) On a conductive support, a photosensitive layer containing an arylamine-based compound represented by the general formula [1] as a charge transporting material and containing a metal-free phthalocyanine, a metal phthalocyanine, or a bisazo pigment as a charge generating material is provided. The electrophotographic photoreceptor according to claim 1, comprising: The electrophotographic photosensitive member according to claim 2, wherein the charge generation material is at least one metal phthalocyanine compound selected from the group consisting of the following a) to c).
a) Oxytitanium phthalocyanine showing diffraction peaks at 9.7 °, 14.2 ° and 27.3 ° in the X-ray diffraction spectrum (2θ ± 0.2 °) b) Bragg angle (2θ) in the X-ray diffraction spectrum Oxytitanium phthalocyanine showing diffraction peaks at 9.3 °, 13.2 °, 26.2 ° and 27.1 ° c) Bragg angle of X-ray diffraction spectrum (2θ ± 0.3 °) Dihydroxysilicon phthalocyanine compound having diffraction peaks at 9.2 °, 14.1 °, 15.3 °, 19.7 ° and 27.1 °

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