JP2004126136A - Electrophotographic photoreceptor, processing cartridge comprising it and electrophotographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor which forms an electron transportation film having high electron transportation ability and being mechanically/ chemically very stable and highly durable, which has improved wear resistance and scratching resistance and further has excellent deposition resistance and which can be used with positive electrostatic charge. <P>SOLUTION: In the electrophotographic photoreceptor having a photosensitive layer on an electrically conductive supporting body, an uppermost layer of the photosensitive layer contains polymer of an electron transportable compound having two or more chain-polymerizable functional groups in a molecule. The electron transportable compound is expressed by formula (1). <P>COPYRIGHT: (C)2004,JPO

Description

【００２２】
開環重合とは、炭素環、オクソ環、窒素ヘテロ環などのひずみを有した不安定な環状構造が触媒の作用で活性化され、開環すると同時に重合を繰り返し鎖状高分子物を生成する反応であるが、この場合基本的にはイオンが活性種として作用するものが大部分である。該開環重合性官能基の具体例を表２に示すがこれらに限定されるものではない。
【００２３】
【表２】

【００２４】
表１及び表２中、Ｒは置換基を有しても良いメチル基、エチル基、プロピル基及びブチル基等のアルキル基、置換基を有しても良いベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基、置換基を有しても良いフェニル基、ナフチル基及びアンスリル基等のアリール基又は水素原子を示す。
【００２５】
上記で説明したような本発明に係わる連鎖重合性官能基の中でも、下記の一般式（４）〜（６）で示されるものが好ましい。
【００２６】
【化１１】

【００２７】
式中、Ｅは水素原子、フッ素、塩素及び臭素等のハロゲン原子、置換基を有してもよいメチル基、エチル基、プロピル基及びブチル基等のアルキル基、置換基を有してもよいベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基、置換基を有してもよいフェニル基、ナフチル基、アンスリル基、ピレニル基、チオフェニル基及びフリル基等のアリール基、メトキシ基、エトキシ基及びプロポキシ基等のアルコキシ基、ＣＮ基、ニトロ基、−ＣＯＯＲ^１５又はＣＯＮＲ^１６Ｒ^１７を示し、
Ｗは置換基を有してもよい２価のフェニレン、ナフチレン、アントラセニレン等のアリーレン基、置換基を有してもよいメチレン、エチレン、ブチレン等の２価のアルキレン基、−ＣＯＯ−、−ＣＨ_２−、−Ｏ−、または−ＣＯＮＲ^１８−で示され、
Ｒ^１５、Ｒ^１６、Ｒ^１７及びＲ^１８は水素原子、フッ素、塩素、臭素及びヨウ素等のハロゲン原子、置換基を有してもよいメチル基、エチル基、プロピル基及びブチル基等のアルキル基、置換基を有してもよいベンジル基及びフェネチル基等のアラルキル基又は置換基を有してもよいフェニル基、ナフチル基及びアンスリル基等のアリール基を示し、Ｒ^１６とＲ^１７は互いに同一であっても異なってもよく、また、ｆは０または１を示す。
【００２８】
Ｅ及びＷ中で有してもよい置換基としては、フッ素、塩素、臭素及びヨウ素等のハロゲン原子、ニトロ基、シアノ基、水酸基、メチル基、エチル基。プロピル基及びブチル基等のアルキル基、メトキシ基、エトキシ基及びプロポキシ基等のアルコキシ基、フェノキシ基及びナフトキシ基等のアリールオキシ基、ベンジル基、フェネチル基、ナフチルメチル基、フルフリル基、チエニル基等のアラルキル基又はフェニル基、ナフチル基、アンスリル基及びピレニル基等のアリール基等が挙げられる。
【００２９】
【化１２】

【００３０】
（式中Ｒ^１９及びＲ^２０は水素原子、置換基を有してもよいメチル基、エチル基、プロピル基及びブチル基等のアルキル基、置換基を有してもよいベンジル基及びフェネチル基等のアラルキル基又は置換基を有してもよいフェニル基及びナフチル基等のアリール基を示し、ｎは１から１０の整数を示す。）
【００３１】
【化１３】

【００３２】
（式中Ｒ^２１及びＲ^２２は水素原子、置換基を有してもよいメチル基、エチル基、プロピル及びブチル基等のアルキル基、置換基を有してもよいベンジル基及びフェネチル基等のアラルキル基又は置換基を有してもよいフェニル基及びナフチル基等のアリール基を示し、式中ｎは０から１０以下の整数を示す。）
尚、上記一般式の（５）及び（６）のＲ^１９、Ｒ^２０、Ｒ^２１及びＲ^２２が有してもよい置換基としてはフッ素、塩素、臭素及びヨウ素等のハロゲン原子、メチル基、エチル基。プロピル基及びブチル基等のアルキル基、メトキシ基、エトキシ基及びプロポキシ基等のアルコキシ基、フェノキシ基及びナフトキシ基等のアリールオキシ基、ベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基又はフェニル基、ナフチル基、アンスリル基及びピレニル基等のアリール基等が挙げられる。
【００３３】
また、上記一般式（４）〜（６）の中でも、更に特に好ましい連鎖重合性官能基としては、下記一般式（７）〜（１３）で示されるものが挙げられる。
【００３４】
【化１４】

【００３５】
さらに上記式（７）〜（１３）の中でも、（７）のアクリロイルオキシ基および（８）のメタクリロイルオキシ基が、重合特性などの点から特に好ましい。
【００３６】
本発明で「連鎖重合性官能基を有する電子輸送性化合物」とは、上記で説明した連鎖重合性基が上記で説明した電子輸送性化合物に官能基として少なくとも２つ以上化学結合している化合物を示す。この場合それらの連鎖重合性官能基はすべて同一でも異なったものであってもよい。
【００３７】
それらの連鎖重合性官能基を少なくとも２つ有する電子輸送性化合物としては下記の一般式（１）である場合が好ましい。
【００３８】
【化１５】

【００３９】
式中、Ａは電子輸送性基を示し；Ｐ^１及びＰ^２は連鎖重合性官能基を示し；Ｐ^１とＰ^２は同一でも異なってもよく；Ｚは置換基を有してもよい有機基を示し；ａ、ｂ及びｄは０以上の整数を示し、ａ＋ｂ×ｄは２以上の整数を示し；また、ａが２以上の場合Ｐ^１は同一でも異なってもよく、ｄが２以上の場合はＰ^２は同一でも異なってもよく、またｂ　が２以上の場合、Ｚ及びＰ^２は同一でも異なってもよい。
【００４０】
尚ここで、「ａが２以上の場合Ｐ^１は同一でも異なってもよく」とは、それぞれ異なるｎ種類の連鎖重合性官能基をＰ^１１，Ｐ^１２，Ｐ^１３，Ｐ^１４，Ｐ^１５・・・・Ｐ^１ｎと示した場合、例えばａ＝３のとき電子輸送性化合物Ａに直接結合する重合性官能基Ｐ^１は３つとも同じものでも、２つ同じで１つは違うもの（例えば、Ｐ^１１とＰ^１１とＰ^１２とか）でも、それぞれ３つとも異なるもの（例えば、Ｐ^１２とＰ^１５とＰ^１７とか）でも良いということを意味するものである（「ｄ　が２以上の場合Ｐ^２は同一でも異なってもよく」というのも、「ｂが２以上の場合、Ｚは同一でも異なってもよい」というのもこれと同様な事を意味するものである）。
【００４１】
上記一般式（１）連鎖重合性官能基を２つ以上有する電子輸送化合物は、還元電位（電子親和力Ｅａに対応）の値が参照電極ＳＣＥ（飽和カルメロ電極）に対して−０．２（ｖ）から−１．２（ｖ）である物が好ましく、特に好ましくは−０．２（ｖ）から−０．８（ｖ）であるものが好ましい。
【００４２】
それは、還元電位が−１．２（ｖ）越えると電荷発生材料からの電荷（電子）の注入が起こりにく残留電位の上昇、感度悪化及び繰り返し使用時の電位変動が大きくなる等の問題が生じ、また−０．２（ｖ）未満では帯電能低下等の問題が生じ易くなる為である。
【００４３】
尚、ここで述べている還元電位は、以下の方法によって測定される。
【００４４】
（還元電位の測定法）
飽和カロメル電極を参照電極とし、電解液に０．１Ｎ　（ｎ−Ｃ_４Ｈ_９）_４Ｎ^＋ＣｌＯ_４ ⁻ジクロロメタン溶液を用い、ポテンシャルスイーパによって作用電極（白金）に印加する電位をスイープし得られた電流―電位曲線がピークを示したときの電位を酸化電位とした。詳しくは、サンプルを０．１Ｎ　（ｎ−Ｃ_４Ｈ_９）_４Ｎ^＋ＣｌＯ_４ ⁻ジクロロメタン溶液に１ｍｍｏｌ％程度の濃度になるように溶解する。そしてこのサンプル溶液に作用電極によって電圧を加え、電圧を０（ｖ）から−１．５（ｖ）に直線的に変化させ（この電流―電位曲線において電流値がピークを示したピークトップの位置の電位をＥ_１）更に、−１．５（ｖ）から０（ｖ）に直線的に変化させた時の電流変化を測定し（この電流―電位曲線において電流値がピークを示したピークトップの位置の電位をＥ_２）電流−電位曲線を得る。この得られたＥ_１＋Ｅ_２／２をここでの還元電位とした。尚、ピークが複数ある場合には、０（ｖ）に最も近い第１還元ピークをそれぞれＥ_１及びＥ_２した。
【００４５】
上記一般式（１）のＡのＰ^１及びＺとの結合部位を水素原子に置き換えた電子輸送化合物の好ましい例として、下記一般式（Ａ−１）から（Ａ−１１）が挙げられるがこれらの化合物に限定されるわけではない。
【００４６】
【化１６】

【００４７】
式中、Ｒ^１，Ｒ^２は水素原子、置換基を有してもよいメチル基、エチル基。プロピル基及びブチル基等の炭素数１０以下のアルキル基、置換基を有してもよいベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基、置換基を有してもよいフェニル基、ナフチル基、アンスリル基、フェナンスリル基、ピレニル基、チオフェニル基、フリル基、ピリジル基、キノリル基、ベンゾキノリル基、カルバゾリル基、フェノチアジニル基、ベンゾフリル基、及びベンゾチオフェニル基等のアリール基、メトキシ基、エトキシ基、プロポキシ基、ブトキシ基等のアルコキシ基、フェノキシ基、ナフトキシ基等のアリールオキシ基、アシル基、エステル基、シアノ基、ニトロ基、アミド基、スルホン酸基、スルホン酸エステル基、スルホン酸アミド基、ヒドロキシ基、アルデヒド基またはハロゲン原子を示し、ｍ≧０、ｎ≧０であり、ただし、ｍ≧２のときＲ^１は互いに異なっていてもよく、ｎ≧２のときＲ^２は互いに異なってもよい。
【００４８】
Ｒ^３，Ｒ^４は置換基を有してもよいメチル基、エチル基。プロピル基及びブチル基等の炭素数１０以下のアルキル基、置換基を有してもよいベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基、置換基を有してもよいフェニル基、ナフチル基、アンスリル基、フェナンスリル基、ピレニル基、チオフェニル基、フリル基、ピリジル基、キノリル基、ベンゾキノリル基、カルバゾリル基、フェノチアジニル基、ベンゾフリル基、及びベンゾチオフェニル基等のアリール基またはエステル基を示す。
【００４９】
Ｑ_１　，Ｑ_２は、それぞれ独立に酸素原子，硫黄原子，Ｃ（ＣＮ）_２　，ＣＲ^５ＣＮ　，ＣＹ_２（Ｙはフッ素、塩素、臭素等のハロゲン原子），Ｃ（ＣＯＯＲ^６）_２　，ＣＲ^７ＣＯＯＲ^８ ，ＮＲ^９ またはＮＣＮのいずれかを表す。Ｑ_３は、酸素原子、硫黄原子またはＳＯ_２を示す。
【００５０】
但し、Ｒ^５，Ｒ^６，Ｒ^７，Ｒ^８，Ｒ^９はそれぞれ独立に水素原子、置換基を有してもよいメチル基、エチル基。プロピル基及びブチル基等の炭素数１０以下のアルキル基、置換基を有してもよいベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基又は置換基を有してもよいフェニル基、ナフチル基、アンスリル基、フェナンスリル基、ピレニル基、チオフェニル基、フリル基、ピリジル基、キノリル基、ベンゾキノリル基、カルバゾリル基、フェノチアジニル基、ベンゾフリル基、及びベンゾチオフェニル基等のアリール基を示す。
【００５１】
【化１７】

【００５２】
は置換基を有してもよいベンゼン環、ナフタレン環、アントラセン環、チオフェン環、フラン環、ピリジン環等のアリール基を示す。
【００５３】
また、上記一般式（１）中のＺは、置換基を有してもよいアルキレン基、置換基を有してもよいアリーレン基、ＣＲ^１０＝ＣＲ^１１（Ｒ^１０及びＲ^１１はアルキル基、アリール基または水素原子を示し、Ｒ^１０及びＲ^１１は同一でも異なっても良い）、Ｃ＝Ｏ、Ｓ＝Ｏ、ＳＯ_２、酸素原子又は硫黄原子より一つあるいは任意に組み合わされた有機基を示す。その中でも下記一般式（２）で示されるものが好ましく、下記一般式（３）で示されるものが特に好ましい。
【００５４】
【化１８】

【００５５】
上記一般式（３）中、Ｘ^１〜Ｘ^３は置換基を有してもよいメチレン基、エチレン基及びプロピレン基等の炭素数２０以下のアルキレン基、（ＣＲ^１２＝ＣＲ^１３）ｍ^２、Ｃ＝Ｏ、Ｓ＝Ｏ、ＳＯ_２、酸素原子又は硫黄原子を示し、Ａｒ^１及びＡｒ^２は置換基を有してもよい２価のアリーレン基（ベンゼン、ナフタレン、アントラセン、フェナンスレン、ピレン、チオフェン、フラン、ピリジン、キノリン、ベンゾキノリン、カルバゾール、フェノチアジン、ベンゾフラン、ベンゾチオフェン、ジベンゾフラン、ジベンゾチオフェン等より２個の水素原子を取り除いた基）を示す。Ｒ^１２及びＲ^１３は置換基を有してもよいメチル基、エチル基プロピル基及びブチル基等のアルキル基、置換基を有してもよいフェニル基、ナフチル基及びチオフェニル基等のアりール基または水素原子を示し、Ｒ^１２及びＲ^１３は同一でも異なっても良い。ｍ^２は１から５の整数、ｐ〜ｔは０から１０の整数を示す（但しｐ〜ｔは同時に０であることはない）。
【００５６】
上記一般式（３）中、Ｘ^４及びＸ^５は（ＣＨ_２）ｍ^３、（ＣＨ＝ＣＲ^１４）ｍ^４、Ｃ＝Ｏ、又は酸素原子を示し、Ａｒ^３は置換基を有してもよい２価のアリーレン基（ベンゼン、ナフタレン、アントラセン、フェナンスレン、ピレン、チオフェン、フラン、ピリジン、キノリン、ベンゾキノリン、カルバゾール、フェノチアジン、ベンゾフラン、ベンゾチオフェン、ジベンゾフラン、ジベンゾチオフェン等より２個の水素原子を取り除いた基）を示す。Ｒ^１４は置換基を有してもよいメチル基、エチル基、プロピル基及びブチル基等のアルキル基、置換基を有しても良いフェニル基、ナフチル基及びチオフェニル基等のアリール基又は水素原子を示す。ｍ^３は１から１０の整数、ｍ^４は１から５の整数、ｕ〜ｗは０から１０の整数を示す（特に０から５の整数の時が特に好ましい。但しｕ〜ｗは同時に０であることはない）。
【００５７】
尚、上述の一般式（１）〜（１３）及び（Ａ−１）〜（Ａ−１１）のＲ^１〜Ｒ^２２、Ａｒ^１〜Ａｒ^３、Ｘ^１〜Ｘ^５、Ｚ及びＱがそれぞれ有してもよい置換基としてはフッ素、塩素、臭素及びヨウ素等のハロゲン原子、ニトロ基、シアノ基、水酸基、メチル基、エチル基。プロピル基及びブチル基等のアルキル基、メトキシ基、エトキシ基及びプロポキシ基等のアルコキシ基、フェノキシ基、ナフトキシ基等のアリールオキシ基、ベンジル基、フェネチル基、ナフチルメチル基、フルフリル基及びチエニル基等のアラルキル基、フェニル基、ナフチル基、アンスリル基及びピレニル基等のアリール基等が挙げられる。
【００５８】
また更に、上記連鎖重合性官能基を有する電子輸送性化合物は電子輸送能として１×１０^−７（ｃｍ^２／ｖ．ｓｅｃ）以上のドリフト移動度を有しているものが好ましい（但し、印加電界：５×１０^４ｖ／ｃｍ）。１×１０^−７（ｃｍ^２／ｖ．ｓｅｃ）未満では電子写真感光体として露光後現像までに電子が十分に移動できないため見かけ上感度が低減し、残留電位も高くなってしまう問題が発生する場合がある。
【００５９】
以下に本発明に係わる、連鎖重合性官能基を有する電子輸送性化合物の代表例を挙げるがこれらに限定されるものではない。
【００６０】
【表３】

【００６１】
【表４】

【００６２】
【表５】

【００６３】
本発明においては，前記同一分子内に二つ以上の連鎖重合性官能基を有する電子輸送性化合物を重合・硬化させることで、その感光層中において、電子輸送能を有する化合物は少なくとも二つ以上の架橋点をもって３次元架橋構造の中に共有結合を介して取り込まれる。前記電子輸送性化合物はそれのみを重合・架橋させる、あるいは他の連鎖重合性基を有する化合物と混合させることのいずれもが可能であり、その種類／比率はすべて任意である。ここでいう他の連鎖重合性基を有する化合物とは、連鎖重合性基を有する単量体あるいはオリゴマー／ポリマーのいずれもが含まれる。電子輸送性化合物の官能基とその他の連鎖重合性化合物の官能基が同一の基あるいは互いに重合可能な基である場合には、両者は共有結合を介した共重合３次元架橋構造をとることが可能である。両者の官能基が互いに重合しない官能基である場合には、感光層は少なくとも二つ以上の３次元硬化物の混合物あるいは主成分の３次元硬化物中に他の連鎖重合性化合物単量体あるいはその硬化物を含んだものとして構成されるが、その配合比率／製膜方法をうまくコントロールすることで、ＩＰＮ（Ｉｎｔｅｒ　　Ｐｅｎｅｔｒａｔｉｎｇ　Ｎｅｔｗｏｒｋ）すなわち相互進入網目構造を形成することも可能である。
【００６４】
また前記電子輸送性化合物と連鎖重合性基を有しない単量体あるいはオリゴマー／ポリマーや連鎖重合性以外の重合性基を有する単量体あるいはオリゴマー／ポリマーなどから感光層を形成してもよい。
【００６５】
さらに場合によっては３次元架橋構造に化学結合的に組み込まれないすなわち連鎖重合性官能基を有しない電子輸送性化合物を含有することも可能である。
【００６６】
また、その他の各種添加剤、テフロン（登録商標）その他の潤滑剤などを含有してもよい。
【００６７】
本発明の感光体の構成は、導電性支持体上に感光層として電荷発生物質を含有する電荷発生層および電荷輸送物質を含有する電荷輸送層をこの順に積層した構成あるいは逆に積層した構成、また電荷発生物質と電荷輸送物質を同一層中に分散した単層からなる構成のいずれの構成をとることも可能である。前者の積層型においては電荷輸送層が二層以上の構成、また後者の単層型においては電荷発生物質と電荷輸送物質を同一に含有する感光層上にさらに電荷輸送層を構成してもよく、さらには電荷発生層あるいは電荷輸送層上に保護層の形成も可能である。これらいずれの場合においても、先の連鎖重合性基を有する電子輸送性化合物および／あるいは前電子輸送性化合物を重合・硬化したものを感光層が含有していればよい。ただし、電子写真感光体としての特性、特に残留電位などの電気的特性および耐久性の点より、電荷発生層／電荷輸送層をこの順に積層した機能分離型の感光体構成が好ましく、本発明の利点も電荷輸送能を低下させることなく表面層の高耐久化が可能になった点にある。
【００６８】
次に本発明による電子写真感光体の製造方法を具体的に示す。
【００６９】
電子写真感光体の支持体としては導電性を有するものであればよく、例えばアルミニウム、銅、クロム、ニッケル、亜鉛およびステンレスなどの金属や合金をドラムまたはシート状に成形したもの、アルミニウムおよび銅などの金属箔をプラスチックフィルムにラミネートしたもの、アルミニウム、酸化インジウムおよび酸化錫などをプラスチックフィルムに蒸着したもの、導電性物質を単独または結着樹脂とともに塗布して導電層を設けた金属、またプラスチックフィルムおよび紙などが挙げられる。
【００７０】
本発明においては導電性支持体の上にはバリアー機能と接着機能をもつ下引き層を設けることができる。
【００７１】
下引き層は感光層の接着性改良、塗工性改良、支持体の保護、支持体上の欠陥の被覆、支持体からの電荷注入性改良、また感光層の電気的破壊に対する保護などのために形成される。下引き層の材料としてはポリビニルアルコール、ポリ−Ｎ−ビニルイミダゾール、ポリエチレンオキシド、エチルセルロース、エチレン−アクリル酸共重合体、カゼイン、ポリアミド、Ｎ−メトキシメチル化６ナイロン、共重合ナイロン、にかわおよびゼラチンなどがしられている。これらはそれぞれに適した溶剤に溶解されて支持体上に塗布される。その際の膜厚としては０．１〜２μｍが好ましい。
【００７２】
本発明の感光体が機能分離型の感光体である場合には電荷発生層および電荷輸送層を積層する。電荷発生層に用いる電荷発生物質としては、セレン−テルル、ピリリウム、チアピリリウム系染料、また各種の中心金属および結晶系、具体的には例えばα、β、γ、εおよびＸ型などの結晶型を有するフタロシアニン化合物、アントアントロン顔料、ジベンズピレンキノン顔料、ピラントロン顔料、トリスアゾ顔料、ジスアゾ顔料、モノアゾ顔料、インジゴ顔料、キナクリドン顔料、非対称キノシアニン顔料、キノシアニンおよびアモルファスシリコーンなどが挙げられる。
【００７３】
機能分離型感光体の場合、電荷発生層は前記電荷発生物質を０．３〜４倍量の結着樹脂および溶剤とともにホモジナイザー、超音波分散、ボールミル、振動ボールミル、サンドミル、アトライターおよびロールミルなどの方法で良く分散し、分散液を塗布し、乾燥されて形成されるか、または前記電荷発生物質の蒸着膜など、単独組成の膜として形成される。その膜厚は５μｍ以下であることが好ましく、特に０．１〜２μｍの範囲であることが好ましい。
【００７４】
結着樹脂を用いる場合の例は、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、フッ化ビニリデン、トリフルオロエチレン、などのビニル化合物の重合体および共重合体、ポリビニルアルコール、ポリビニルアセタール、ポリカーボネート、ポリエステル、ポリスルホン、ポリフェニレンオキサイド、ポリウレタン、セルロース樹脂、フェノール樹脂、メラミン樹脂、ケイ素樹脂、エポキシ樹脂などが挙げられる。
【００７５】
本発明における前記連鎖重合性官能基を有する電子輸送性化合物は、前述した電荷発生層上に電荷輸送層として、もしくは電荷発生層上に電荷輸送物質と結着樹脂からなる電荷輸送層を形成した後に電子輸送能力を有する表面保護層として用いることができる。いずれの場合も前記表面層の形成方法は、前記正孔輸送性化合物を含有する溶液を塗布後、重合／硬化反応をさせるのが一般的であるが、前もって該正孔輸送性化合物を含む溶液を反応させて硬化物を得た後に再度溶剤中に分散あるいは溶解させたものなどを用いて、表面層を形成することも可能である。これらの溶液を塗布する方法は、例えば浸漬コーティング法、スプレーコーティング法、カーテンコーティング法およびスピンコーティング法などが知られているが、効率性／生産性の点からは浸漬コーティング法が好ましい。
【００７６】
また蒸着、プラズマその他の公知の製膜方法が適宜選択できる。
【００７７】
本発明において連鎖重合性基を有する電子輸送性化合物は放射線により重合・硬化させることが好ましい。放射線による重合の最大の利点は重合開始剤を必要としない点であり、これにより非常に高純度な三次元感光層マトリックスの作製が可能となり、良好な電子写真特性が確保される点である。また、短時間でかつ効率的な重合反応であるがゆえに生産性も高く、さらには放射線の透過性の良さから、厚膜時や添加剤などの遮蔽物質が膜中に存在する際の硬化阻害の影響が非常に小さいことなどが挙げられる。ただし、連鎖重合性基の種類や中心骨格の種類によっては重合反応が進行しにくい場合があり、その際には影響のない範囲内での重合開始剤の添加は可能である。この際使用する放射線とは電子線およびγ線である。電子線照射をする場合、加速器としてはスキャニング型、エレクトロカーテン型、ブロードビーム型、パルス型およびラミナー型などいずれの形式も使用することが出来る。電子線を照射する場合に、本発明の感光体においては電気特性および耐久性能を発現させる上で照射条件が非常に重要である。本発明において、加速電圧は２５０ＫＶ以下が好ましく、最適には１５０ＫＶ以下である。また照射線量は好ましくは１Ｍｒａｄから１００Ｍｒａｄの範囲、より好ましくは３Ｍｒａｄから５０Ｍｒａｄの範囲である。加速電圧が上記を越えると感光体特性に対する電子線照射のダメージが増加する傾向にある。また、照射線量が上記範囲よりも少ない場合には硬化が不十分となりやすく、線量が多い場合には感光体特性の劣化がおこりやすいので注意が必要である。
【００７８】
前記連鎖重合性基を有する電子輸送性化合物を電荷輸送層として用いた場合の前記電子輸送性化合物の量は、重合硬化後の電荷輸送層膜の全重量に対して、前記式（１）で示される連鎖重合性官能基を有する電子輸送性基Ａの水素付加物が分子量換算で２０％以上、好ましくは４０％以上含有されていることが望ましい。それ以下であると電荷輸送能が低下し、感度低下および残留電位の上昇などの問題点が生ずる。この場合の電荷輸送層としての膜厚は１〜５０μｍであることが好ましく、特には３〜３０μｍであることが好ましい。
【００７９】
前記電子輸送性化合物を電荷発生層／電荷輸送層上に表面保護層として用いた場合、その下層に当たる電荷輸送層は適当な電子輸送化合物、例えばベンゾキノン誘導体、ジフェノキノン誘導体、ナフトキノン誘導体、シクロペンタジエン誘導体、インデノン誘導体、ベンゾオキサゾール誘導体、ベンゾチアゾール誘導体、イミド誘導体、ジイミド誘導体、４−オキソチオピラン−１，１−ジオキシド誘導体、フルオレノン誘導体などの低分子化合物などを適当な結着樹脂（前述の電荷発生層用樹脂の中から選択できる）とともに溶剤に分散／溶解した溶液を前述の公知の方法によって塗布、乾燥して形成することができる。この場合の電荷輸送物質と結着樹脂の比率は、両者の全重量を１００とした場合に電荷輸送物質の重量３０〜１００が望ましく、好ましくは５０〜１００の範囲で適宜選択される。電荷輸送物質の量がそれ以下であると、電荷輸送能が低下し、感度低下および残留電位の上昇などの問題点が生ずる。電荷輸送層の膜厚は、上層の表面保護層と合わせた総膜厚が１〜５０μｍとなるように決定され、好ましくは５〜３０μｍの範囲で調整される。
【００８０】
本発明においては上述のいずれの場合においても、前記連鎖重合性基を有する電子輸送性化合物の硬化物を含有する感光層に、前記電子輸送化合物を含有することが可能である。
【００８１】
単層型感光層の場合は、前記電子輸送性化合物を含む溶液中に同時に電荷発生物質が含まれることになり、この溶液を適当な下引き層あるいは中間層を設けても良い導電性支持体上に塗布後重合／硬化させて形成される場合と、導電性支持体上に設けられた電荷発生物質および電荷輸送物質から構成される単層型感光層上に前記電子輸送性化合物を含有する溶液を塗布後、重合／硬化させる場合のいずれもが可能である。
【００８２】
本発明における感光層には、各種添加剤を添加することができる。該添加剤とは酸化防止剤および紫外線吸収剤などの劣化防止剤や、テトラフルオロエチレン樹脂粒子およびフッ化カーボンなどの潤剤などである。
【００８３】
図１に本発明の電子写真感光体を有するプロセスカートリッジを有する電子写真装置の概略構成を示す。図において、１はドラム上の本発明の電子写真感光体であり、軸２を中止に矢印方向に所定の周速度で回転駆動される。感光体１は、回転過程において、一次帯電手段３によりその周面に正または負の所定電位の均一帯電を受け、次いでスリット露光やレーザービーム走査露光などの像露光手段（不図示）からの画像露光光４を受ける。こうして感光体１の周面に静電潜像が順次形成されていく。形成された静電潜像は、次いで現像手段５によりトナー現像され、現像されたトナー現像像は、不図示の給紙部から感光体１と転写手段６との間に感光体１の回転と同期取り出されて給紙された転写材７に、転写手段６により順次転写されていく。像転写を受けた転写材７は、感光体面から分離されて像定着手段８へ導入されて像定着をうけることにより複写物（コピー）として装置外へプリントアウトされる。像転写後の感光体１の表面は、クリーニング手段９によって転写残りトナーの除去を受けて清浄面化され、さらに前露光手段（不図示）からの前露光光１０により助電処理された後、繰り返し画像形成に使用される。なお、一次帯電手段３が帯電ローラーなどを用いた接触帯電手段である場合は、前露光は必ずしも必要ではない。本発明においては、上述の電子写真感光体１、一次帯電手段３、現像手段５およびクリーニング手段９などの構成要素のうち、複数のものをプロセスカートリッジとして一体に結合して構成しこのプロセスカートリッジを複写機やレーザービームプリンターなどの電子写真装置本体に対して着脱可能に構成してもよい。例えば、一次帯電手段３、現像手段５およびクリーニング手段９の少なくとも一つを感光体１とともに一体に支持してカートリッジ化して、装置本体のレール１２などの案内手段を用いて装置本体に着脱可能なプロセスカートリッジ１１とすることができる。また、画像露光光４は、電子写真装置が複写機やプリンターである場合には、原稿からの反射光や透過光、あるいはセンサーで原稿を読みとり、信号化し、この信号に従って行われるレーザービームの走査、ＬＥＤアレイの駆動および液晶シャッターアレイの駆動などにより照射される光である。
【００８４】
本発明の電子写真感光体は電子写真複写機に利用するのみならず、レーザービームプリンター、ＣＲＴプリンター、ＬＥＤプリンター、液晶プリンターおよびレーザー製版などの電子写真応用分野にも広く用いることができる。
【００８５】
【実施例】
（実施例１）
まず導電層用の塗料を以下の手順で調整した。１０％の酸化アンチモンを含有する酸化スズで被覆した導電性酸化チタン粉体５０部（質量部、以下同様）、フェノール樹脂２５部、メチルセロソルブ２０部、メタノール５部およびシリコーンオイル（ポリジメチルシロキサンポリオキシアルキレン共重合体、平均分子量３０００）０．００２部を、φ１ｍｍガラスビーズ入りサンドミル装置で２時間分散して調整した。この塗料を３０φのアルミニウムシリンダー上に浸漬塗布方法で塗布し、１４０℃で３０分乾燥して、膜厚２０μｍの導電層を形成した。
【００８６】
次に、Ｎ−メトキシメチル化ナイロン５部をメタノール９５部中に溶解し、中間層用塗料を調整した。この塗料を前記の導電層上に浸漬コーティング法によって塗布し、１００℃で２０分間乾燥して、０．６μｍの中間層を形成した。
【００８７】
次にＣｕＫαのＸ線回折におけるブラッグ角２θ±０．２°の７．４°及び２８．２°に強いピークを有する結晶型持つヒドロキシガリウムフタロシアニン化合物４部とポリビニルブチラール樹脂（ブチラール化度６５モル％、数平均分子量３５０００）２部をシクロヘキサノン８０部に添加し、ガラスビーズとともにサンドミルで４時間分散し、これに８０部の酢酸エチルを加え希釈し、これを中間層上に乾燥後の膜厚が０．２μｍになるように浸漬コーティング法で塗布し電荷発生層を形成した。
【００８８】
次いで、表３の化合物例Ｎｏ．１９の電子輸送性化合物６０部をモノクロロベンゼン３０部およびジクロロメタン３０部の混合溶媒中に溶解し、電荷輸送層用塗料を調整した、この塗料を前記の電荷発生層上にコーティングし、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量１０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚１５μｍの電荷輸送層を形成し、電子写真感光体を得た。
【００８９】
作製した電子写真感光体について、経時析出性、電子写真特性、耐久性を評価した。経時析出性については、複写起用のウレタンゴム製のクリーニングブレードを感光体表面に圧接し、７５℃で保存し析出性に対する加速試験を行った。評価は１４日後に感光体表面を顕微鏡により観察し析出の有無を判定した。析出のない場合はさらに３０日後まで試験を継続した。電子写真特性および耐久性は、この感光体をキヤノン（株）製ＧＰ５５を正帯電用に改造した機械に装着して評価した。初期の感光体特性［暗部電位Ｖｄ、光減衰感度（暗部電位＋７００Ｖ設定で＋２００Ｖに光減衰させるために必要な光量）および残留電位Ｖｓｌ（光減衰感度光量の１０倍の光量を照射したときの電位）］を測定し、さらに１５０００枚の通紙耐久試験を行い、目視による画像欠陥の発生有無を観察、感光体の削れ量および耐久後の前記感光体特性を測定し、各々の変化値△Ｖｄ、△Ｖｌ（初期にＶｌが＋２００Ｖとなる光量と同量の光量を耐久後に照射したときのＶｌの変化量）および△Ｖｓｌを求めた。
【００９０】
結果を表６に示すが、本発明の感光体では析出は発生せず、また感光体特性が良好であり、耐久での削れ量が少なく、かつ耐久においても感光体特性にはほとんど変化がみられないというように、非常に安定した良好な特性を示している。
【００９１】
（実施例２〜１６）
実施例１における電子輸送性化合物Ｎｏ．１９を表６に示した化合物に変えた以外は、実施例１と同様に電子写真感光体を作製し評価した。その結果を表６に示す。
【００９２】
（実施例１７）
実施例１において電子輸送性化合物Ｎｏ．１９の量を４８部とし、さらに下記式を有するアクリレートモノマーを１２部添加した以外は実施例１と同様
【００９３】
【化１９】

【００９４】
に電子写真感光体を作製し評価した。その結果を表６に示す。
【００９５】
（実施例１８〜２１）
実施例１において電子線の照射条件を表６に示したように変えた以外は実施例１と同様に電子写真感光体を作製し、評価した。削れ量、耐久画像は良好であったが、照射線量を上げることで初期の電子写真特性において、若干の感度ダウンや残留電位の上昇が見られた。その結果を表６に示す。
【００９６】
（実施例２２）
実施例１と同様に導電層、中間層および電荷発生層を形成した後、表３の電子輸送性化合物例Ｎｏ．１４　６０部および下記構造式の光重合開始剤０．６部をモノクロロベンゼン３０部およびジクロロメタン３０部の混合溶媒中に
【００９７】
【化２０】

【００９８】
溶解し、電荷輸送層用塗料を調整した、この塗料を前記の電荷発生層上にコーティングし、メタルハライドランプを用いて５００ｍＷ／ｃｍ^２の光強度で硬化させることによって膜厚１５μｍの電荷輸送層を形成し、電子写真感光体を得た。得られた感光体を実施例１と同様に評価した。その結果を表６に示す。
【００９９】
（実施例２３）
実施例２２において光重合開始剤を下記熱重合開始剤とし、紫外線硬化のかわりに硬化反応を１５０℃／１時間とした以外は実施例１と同様に電子写真感光体を作製し評価した。その結果を表６に示す。
【０１００】
【化２１】

【０１０１】
（実施例２４）
実施例１と同様に導電層、中間層を形成した後、下記構造式の正孔輸送性化合物２０部およびポリカーボネート樹脂（Ｚ型；重量平均分子量：
【０１０２】
【化２２】

【０１０３】
５００００）１０部をモノクロロベンゼン５０部およびジクロロメタン２０部の混合溶媒中に溶解して調整した電荷輸送層用塗料を用いて、前記中間層上に電荷輸送層を形成した。このときの電荷輸送層の膜厚は１０μｍであった。次いで実施例１で用いた電荷発生用塗料を用い乾燥後の膜厚が２．０μｍになるように浸漬コーティング法で塗布し電荷発生層を形成した。
【０１０４】
次いで、表５の電子輸送性化合物Ｎｏ．６０　６０部をモノクロロベンゼン５０部およびジクロロメタン３０部の混合溶媒中に溶解し、表面保護層用塗料を調整した。この塗料をスプレーコーティング法により先の電荷輸送層上に塗布し、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量１０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚５μｍの表面保護層を形成し、電子写真感光体を得た。この感光体を実施例１と同様に評価した。その結果を表６に示す。
【０１０５】
（実施例２５）
実施例１と同様に導電層、中間層および電荷発生層を形成した後、下記構造式のナフタレンテトラカルボン酸ジイミド誘導体化合物をそれぞれ４部
【０１０６】
【化２３】

【０１０７】
及びポリカーボネート樹脂（Ｚ型；重量平均分子量：５００００）１０部をモノクロロベンゼン５０部およびジクロロメタン２０部の混合溶媒中に溶解して調整した電荷輸送層用塗料を用いて、前記電荷発生層上に電荷輸送層を形成した。このときの電荷輸送層の膜厚は１５μｍであった。次いで、表３の電子輸送性化合物例Ｎｏ．１９　６０部をモノクロロベンゼン５０部およびジクロロメタン３０部の混合溶媒中に溶解し、表面保護層用塗料を調整した。この塗料をスプレーコーティング法により先の電荷輸送層上に塗布し、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量１０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚５μｍの表面保護層を形成し、電子写真感光体を得た。この感光体を実施例１と同様に評価した。その結果を表６に示す。
【０１０８】
（実施例２６）
実施例１と同様に導電層および中間層を形成した後、β型オキシチタニウムフタロシアニン結晶を３部、正孔輸送材料として下記構造式（Ａ）の化合物４０部、電子輸送材料として下記構造式（Ｂ）の化合物４０部、
【０１０９】
【化２４】

【０１１０】
ポリカーボネート樹脂（Ｚ型；重量平均分子量：５００００）１００部およびテトラヒドロフラン７００部をボールミルで混合分散した単層型感光体の塗料を塗布し、乾燥後の膜厚が１３μｍの感光層を形成した。次いで、表４の電子輸送性化合物Ｎｏ．３２　６０部をモノクロロベンゼン５０部およびジクロロメタン３０部の混合溶媒中に溶解し、表面保護層用塗料を調整した。この塗料をスプレーコーティング法により先の電荷輸送層上に塗布し、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量１０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚５μｍの表面保護層を形成し、電子写真感光体を得た。この感光体を実施例１と同様に評価した。その結果を表６に示す。
【０１１１】
【表６】

【０１１２】
（比較例１）
実施例１において導電層、中間層及び電荷発生層を形成した後、下記構造式の電子輸送性化合物１５部およびポリメチルメタクリレート樹脂（数平均分子量：約４００００）１５部をモノクロロベンゼン５０部およびジクロロメタン２０部の混合溶媒中に溶解して調整した電荷輸送層用塗料を用いて、前記電荷発生層上に電荷輸送層を形成した。このときの電荷輸送層の膜厚は１５μｍであった。
【０１１３】
【化２５】

【０１１４】
この電子写真感光体を実施例１と同様に評価した結果、１４日後に析出が見られた。一方初期の電子写真特性は良好であったが、耐久での表面層の削れ量が多く、かぶり、傷などの画像欠陥が発生している。さらに８０００枚以降は削れにより電荷輸送層の膜厚がうすくなり、帯電不良が発生し、画像形成が不可能となった。その結果を表７に示す。
【０１１５】
（比較例２）
比較例１においてポリメチルメタクリレート樹脂のかわりにポリカーボネート樹脂（Ｚ型；重量平均分子量：５００００）を用いた以外は、比較例１と同様に電子写真感光体を作製し、評価した。析出試験では１４日後に析が観察された。またポリメチルメタクリレート樹脂の場合に比べて耐久性は若干向上したものの十分ではなく、１２０００枚より帯電不良が発生し、画像形成が不可能となった。その結果を表７に示す。
【０１１６】
（比較例３）
比較例２の電子輸送性化合物１０部、ポリカーボネート樹脂１５部とした以外は比較例２と同様に電子写真感光体を作製し、評価した結果、比較例２に比べて耐久性は向上したものの、電荷輸送物質間の距離が広がったことによって電荷輸送能が低下し、感度低下および残留電位の上昇が見られた。その結果を表７に示す。
【０１１７】
（比較例４）
保護層を形成しなかった以外は、実施例２４と同様にして感光体を作成し評価した。初期より帯電不良およびカブリが発生し５００枚より画像形成評価に値しないような画になった。その結果を表７に示す。
【０１１８】
（比較例５）
保護層を形成しなかった以外は、実施例２５と同様にして感光体を作成し評価した。析出試験では３０日後に析が観察された。耐久性に関しては十分ではなく、１３０００枚より帯電不良が発生し、画像形成が不可能となった。その結果を表７に示す。
【０１１９】
（比較例６）
保護層を形成しなかった以外は、実施例２６と同様にして感光体を作成し評価した。耐久性に関しては十分ではなく、８００枚より帯電不良及びカブリが発生し、５０００枚より帯電不良で画像形成が不可能となった。その結果を表７に示す。
【０１２０】
（比較例７）
実施例２５と同様に導電層、中間層、電荷発生層および電荷輸送層を形成した後、下記構造式のアクリルモノマー５０部をテトラヒドロフラン５０部
【０１２１】
【化２６】

【０１２２】
に溶解し表面保護層用塗料を調整した。この塗料をスプレーコーティング法により先の電荷輸送層上に塗布し、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量３０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚５μｍの表面保護層を形成し、電子写真感光体を得た。この感光体を実施例１と同様に評価した。初期より残留電位が高く画出しおよび電位変動等の評価は出来なかった。その結果を表７に示す。
【０１２３】
（比較例８）
特開平０９−１９４５３５に開示されているのと同様な方法で合成し、下記の電子輸送性ポリマーを（重量平均分子量：１００００、還元電位：−０．９３　ｖ
）得た。
【０１２４】
【化２７】

【０１２５】
実施例１において導電層、中間層及び電荷発生層を形成した後、上記ポリマー１０部をモノクロロベンゼン４０部およびジクロロメタン１０部の混合溶媒中に溶解して調整した電荷輸送層用塗料を用いて、浸漬塗布により電荷輸送層を形成した。このときの電荷輸送層の膜厚は１５μｍであった。この電子写真感光体を実施例１と同様に評価した。初期の電位特性及び耐久の電位特性は十分ではなくかつ耐久画像も７０００枚より傷及びカブリが発生した。その結果を表７に示す。
【０１２６】
（比較例９）
特開平１１−１１９４５８に開示されている下記化合物０．４部と
【０１２７】
【化２８】

【０１２８】
シリコンハードコート材料（Ｘ−４０−２２３９；信越化学社製）０．５部およびｎ−ブチルエーテル３部とを混合した保護層用塗料を調整した。実施例２４と同様に導電層、中間層および電荷発生層を形成した後、この保護層用塗料を電荷発生層上にスプレーコーティング法により塗布し、１００℃で１０分間乾燥表面保護層を作成した。この電子写真感光体を実施例１と同様に評価した。削れ性はかなり良好なものの、初期の電位特性及び耐久の電位特性は十分ではなくかつ耐久画像も１０００枚よりカブリが発生した。その結果を表７に示す。
【０１２９】
【表７】

【０１３０】
（実施例２７）
アルマイト処理されたアルミニウムシリンダー上に、β型オキシチタニウムフタロシアニン結晶を３部、正孔輸送材料として実施例２６の化合物（Ａ）５０部、表３の電子輸送化合物例Ｎｏ．２０　５０部、ポリカーボネート樹脂（Ｚ型；重量平均分子量：４００００）３０部およびおよびテトラヒドロフラン７００部をボールミルで混合分散した単層型感光体の塗料を浸漬塗布し、５０℃で１０分間乾燥させた後に、加速電圧１５０ＫＶ、照射線量１０Ｍｒａｄの条件で電子線を照射し樹脂を硬化し、膜厚１５μｍの単層型電子写真感光体を得た。この感光体をレーザービームプリンター（Ｌａｓｅｒ　Ｊｅｔ４０００：ヒューレットパッカード製）の改造機のシリンダーに貼り付けて、初期暗部電位（Ｖｄ）が−７００（Ｖ）になるように帯電設定をし、これに波長７８０（ｎｍ）のレーザー光を照射して−７００（Ｖ）の電位を−２００（Ｖ）まで下げるのに必要な光量（ＥΔ５００）を測定し感度とした。さらに、２０（μＪ／ｃｍ^２）の光量を照射した場合の電位を残留電位（Ｖｒ）として初期特性を測定した。その結果は、ＥΔ５００；０．４２（μＪ／ｃｍ^２）、Ｖｒ；９０（ｖ）であった。
【０１３１】
更に、連続２０００枚の通紙耐久を行っても画像欠陥のない良好な画像が得られ、２０００枚終了時でのドラムの削れ量は０．４μｍであった。
【０１３２】
（実施例２８）
実施例２７の化合物（Ａ）の替わりに下記構造式の化合物を用いた以外は
【０１３３】
【化２９】

【０１３４】
実施例２７と同様に感光体を作成し同様な評価をした。その結果は、ＥΔ５００；０．３８（μＪ／ｃｍ^２）、Ｖｒ；７５（ｖ）、２０００枚終了時でのドラムの削れ量は０．１５μｍであった。
【０１３５】
（比較例１０）
アルマイト処理されたアルミニウムシリンダー上に、β型オキシチタニウムフタロシアニン結晶を３部、正孔輸送材料として実施例２６の化合物（Ａ）５０部、下記電子輸送化合物
【０１３６】
【化３０】

【０１３７】
５０部、ポリカーボネート樹脂（Ｚ型；重量平均分子量：４００００）１００部およびおよびテトラヒドロフラン　７００部をボールミルで混合分散した単層型感光体の塗料を浸漬塗布し膜厚１５μｍの単層型電子写真感光体を得た。この感光体を実施例２７と同様な評価を行った。その結果は、ＥΔ５００；０．５５（μＪ／ｃｍ^２）、Ｖｒ；１１０（ｖ）、２０００枚終了時でのドラムの削れ量は２．９μｍであった。
【０１３８】
【発明の効果】
本発明の電子写真感光体は耐析出性、耐磨耗性および耐傷性に優れた効果を有する。さらに、感度、残留電位などの電子写真特性も非常に良好であり、また繰り返し使用時にも安定した性能を発揮することができる。
【０１３９】
また、該電子写真感光体の効果は、該電子写真感光体を有するプロセスカートリッジおよび電子写真装置においても当然に発揮され、長期間高画質が維持される。
【図面の簡単な説明】
【図１】本発明の電子写真感光体を有するプロセスカートリッジを有する電子写真装置の概略構成の例を示す図である。
【符号の説明】
１　　電子写真感光体
２　　軸
３　　一次帯電手段
４　　画像露光光
５　　現像手段
６　　転写手段
７　　転写材
８　　像定着手段
９　　クリーニング手段
１０　　前露光光
１１　　プロセスカートリッジ
１２　　レール[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrophotographic photosensitive member, an electrophotographic apparatus provided with the electrophotographic photosensitive member, and a facsimile.
[0002]
[Prior art]
Conventionally, as a photoconductive material used in an electrophotographic photoreceptor, an inorganic photoreceptor having a photosensitive layer containing selenium, zinc oxide, cadmium or the like as a main component has been widely used. These have some basic characteristics as a photoreceptor, but have problems such as difficulty in film formation, poor plasticity, and high production cost. Further, inorganic photoconductive materials are generally highly toxic, and there are great restrictions on production and handling.
[0003]
On the other hand, a photoreceptor containing an organic photoconductive material as a main component has many advantages, such as compensating for the above-mentioned disadvantages of an inorganic photoreceptor, and has been receiving attention in recent years. Have been. As such an organic photoreceptor, a function-separated type electrophotographic photoreceptor in which a charge generation function and a charge transport function are respectively assigned to different substances has brought improvements in sensitivity and durability. Such a function-separated type photoreceptor has an advantage that a material selection range of a charge generation material and a charge transport material is wide, and an electrophotographic photoreceptor having arbitrary characteristics can be relatively easily prepared.
[0004]
However, most of these function-separated type photoconductors are photoconductors of a type in which a charge transport layer is laminated on a charge generation layer in this order, and most of the photoconductors having this configuration are used in a negative charging process. . The reason for adopting such a configuration is that organic materials having a sufficient charge mobility even in a high-speed electrophotographic process have been almost always limited to hole transport materials having only the property of hole transport. In order to minimize the fatigue of electrostatic characteristics and maintain the mechanical strength of the photoreceptor sufficiently during the process, the function of charge generation and charge transfer is separated for each layer. This is because a photoconductor having a laminated structure in which a charge transport layer having an organic material having a hole transport property is disposed on the surface thereof has been considered to be the most reasonable. However, such a function-separated type electrophotographic photosensitive member presents a new problem at present.
[0005]
One of the problems is that electrophotography using an organic photoreceptor that is used for negative charging generates a large amount of ozone due to charging, and consequently pollutes the environment and oxidizes and degrades the photoreceptor. In order to prevent this, a system that does not generate ozone, a system that recovers ozone in the apparatus, and the like are required, and there is a disadvantage that the process and the system are complicated.
[0006]
Therefore, research and development of a positively charged photoreceptor that generates a small amount of ozone during charging has been actively performed in recent years. For example, a photoconductor having a single layer structure in which a charge generation material and a hole transport material are dispersed in a binder resin in one layer, or a charge generation material, a hole transport material, and an electron transport material in one layer In recent years, a large number of single-layer photoreceptors formed by dispersing in a binder resin have been proposed. (For example, refer to Patent Documents 1 to 11)
[0007]
However, the photoreceptor for positive charging described above causes dielectric breakdown due to electric shock at the time of charging, image defects such as white spots and black spots are likely to occur, and the dispersion layer forms a surface layer, There are drawbacks such as poor mechanical wear resistance. In order to prevent this, it is conceivable to provide a protective layer on the photoreceptor. In this case, however, the residual potential increases in the process of repeated image formation, causing background fog, and the electrophotographic performance becomes poor. A problem that easily deteriorates occurs.
[0008]
Therefore, in recent years, an electron transporting material having a certain level of carrier transporting ability has been developed while being inferior to the carrier transporting ability of a hole transporting substance such as a triarylamine. An electrophotographic photoreceptor having a positively-charged laminated structure has been proposed. (For example, see Patent Documents 12 to 21.)
[0009]
However, even with the above-mentioned laminated photoreceptor, there are problems in that the carrier of the electron transport material is not sufficiently moved and the sensitivity is poor, and the resulting fluctuation in the residual potential upon repeated use is large. To compensate for this, if the amount of the electron transporting material is increased, the compatibility with the binder resin will be poor, and if the amount is increased, the durability will still increase even if the amount is increased (wear and scratches on the surface layer ) Is significantly reduced. As described above, the laminated electrophotographic photoreceptor using the electron transport material has at least some problems such as sensitivity, potential characteristics, and durability, and has not yet been put to practical use.
[0010]
Further, in order to solve the above-mentioned problem, a method of polymerizing and using an electron transport compound has recently been proposed. (For example, see Patent Documents 22 to 24.)
[0011]
However, even with the photoreceptor having the above-described configuration, the mechanical strength is still not sufficient, the potential fluctuation during repeated use is large, and the sensitivity is poor. At present, an electrophotographic photoreceptor that can meet the demand for higher image quality has not been obtained, and needs to be improved.
[0012]
[Patent Document 1]
JP-A-61-48861
[Patent Document 2]
JP-A-2-37354
[Patent Document 3]
JP-A-3-290666
[Patent Document 4]
JP-A-4-338760
[Patent Document 5]
JP-A-5-992
[Patent Document 6]
JP-A-6-123984
[Patent Document 7]
JP-A-6-123985
[Patent Document 8]
JP-A-6-130688
[Patent Document 9]
JP-A-6-27693
[Patent Document 10]
JP-A-8-334910
[Patent Document 11]
JP-A-11-65141
[Patent Document 12]
JP-A-60-69657
[Patent Document 13]
JP-A-61-233750
[Patent Document 14]
JP-A-3-256050
[Patent Document 15]
JP-A-4-285670
[Patent Document 16]
JP-A-4-327555
[Patent Document 17]
JP-A-6-43673
[Patent Document 18]
JP-A-6-26612
[Patent Document 19]
JP-A-6-273952
[Patent Document 20]
JP-A-8-248553
[Patent Document 21]
JP-A-10-10760
[Patent Document 22]
JP-A-8-134019
[Patent Document 23]
JP-A-9-194535
[Patent Document 24]
JP-A-11-119458
[0013]
[Problems to be solved by the invention]
An object of the present invention is to solve the above problems in the prior art. That is, first, a highly durable electron transporting film having high electron transporting ability and extremely stable mechanically / chemically is formed, the abrasion resistance and the scratch resistance are improved, and the deposition resistance is excellent. An object of the present invention is to provide an electrophotographic photoreceptor that can be used with positive charging.
[0014]
Second, it is an object of the present invention to provide a positively chargeable electrophotographic photoreceptor capable of exhibiting extremely small potential fluctuations during repeated use and exhibiting stable performance even during repeated use.
[0015]
Third, the present invention provides an electrophotographic photoreceptor which has improved surface abrasion and scratch resistance of the photoreceptor, has a long service life, can be used for positive charge with high image quality, and a process cartridge and an electrophotographic apparatus having the electrophotographic photoreceptor. Is to do.
[0016]
[Means for Solving the Problems]
The present inventors have conducted extensive studies and found that, in an electrophotographic photoreceptor having a photosensitive layer on a conductive support, the photosensitive layer has two or more chain-polymerizable functional groups in the same molecule. It has been found that an electrophotographic photoreceptor characterized in that it contains a compound obtained by polymerizing or cross-linking and curing an electron transporting compound and the electron transporting compound solves the above-mentioned problems.
[0017]
Further, according to the present invention, there is provided a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
The details of the present invention will be described below.
[0019]
First, the chain polymerizable functional group in the present invention will be described. The term chain polymerization in the present invention refers to the former type of polymerization reaction when the production reaction of a macromolecular substance is largely divided into chain polymerization and sequential polymerization, and is described in detail in, for example, `` Basic '' (New Edition), July 25, 1995 (1st edition, 8th press), p. As described in 24, the form mainly refers to unsaturated polymerization, ring-opening polymerization and isomerization polymerization in which the reaction proceeds via an intermediate such as a radical or ion. The chain polymerizable functional group P in the above formula (1) means a functional group capable of the above-mentioned reaction mode, and here, it occupies most of the functional group, and includes unsaturated polymerizable or ring-opening polymerizable functional groups having a wide application range. A specific example will be described.
[0020]
The unsaturated polymerization is a reaction in which an unsaturated group, for example, C ＝ C, C≡C, C ＝ O, C ＝ N, C≡N, or the like is polymerized by a radical, an ion, or the like.
In most cases, C = C. Specific examples of the unsaturated polymerizable functional group are shown in Table 1, but are not limited thereto.
[0021]
[Table 1]

[0022]
In ring-opening polymerization, an unstable cyclic structure having a strain, such as a carbon ring, an oxo ring, or a nitrogen hetero ring, is activated by the action of a catalyst and repeats polymerization at the same time as ring opening to produce a chain polymer. The reaction is a reaction, and in this case, most of the ions basically act as active species. Specific examples of the ring-opening polymerizable functional group are shown in Table 2, but are not limited thereto.
[0023]
[Table 2]

[0024]
In Tables 1 and 2, R represents an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group which may have a substituent, a benzyl group which may have a substituent, a phenethyl group, and a naphthylmethyl group. , An aralkyl group such as a furfuryl group and a thienyl group, an aryl group such as a phenyl group, a naphthyl group and an anthryl group which may have a substituent, or a hydrogen atom.
[0025]
Among the chain polymerizable functional groups according to the present invention as described above, those represented by the following general formulas (4) to (6) are preferable.
[0026]
Embedded image

[0027]
In the formula, E is a hydrogen atom, a halogen atom such as fluorine, chlorine and bromine, an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group which may have a substituent, and may have a substituent. Benzyl group, phenethyl group, naphthylmethyl group, aralkyl group such as furfuryl group and thienyl group, phenyl group which may have a substituent, naphthyl group, anthryl group, pyrenyl group, aryl group such as thiophenyl group and furyl group, Alkoxy groups such as methoxy group, ethoxy group and propoxy group, CN group, nitro group, -COOR^FifteenOr CONR¹⁶R¹⁷Indicates that
W represents an arylene group such as divalent phenylene, naphthylene and anthracenylene which may have a substituent, a divalent alkylene group such as methylene, ethylene and butylene which may have a substituent, -COO- and -CH₂-, -O-, or -CONR¹⁸-,
R^Fifteen, R¹⁶, R¹⁷And R¹⁸Is a hydrogen atom, a halogen atom such as fluorine, chlorine, bromine and iodine, an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group which may have a substituent, and a benzyl group which may have a substituent. And an aralkyl group such as a phenethyl group or an aryl group such as a phenyl group, a naphthyl group and an anthryl group which may have a substituent;¹⁶And R¹⁷May be the same or different, and f represents 0 or 1.
[0028]
Substituents which may be present in E and W include halogen atoms such as fluorine, chlorine, bromine and iodine, nitro groups, cyano groups, hydroxyl groups, methyl groups and ethyl groups. Alkyl groups such as propyl group and butyl group, alkoxy groups such as methoxy group, ethoxy group and propoxy group, aryloxy groups such as phenoxy group and naphthoxy group, benzyl group, phenethyl group, naphthylmethyl group, furfuryl group, thienyl group, etc. And an aryl group such as a phenyl group, a naphthyl group, an anthryl group and a pyrenyl group.
[0029]
Embedded image

[0030]
(Where R¹⁹And R²⁰Has a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group which may have a substituent, an aralkyl group or a substituent such as a benzyl group or a phenethyl group which may have a substituent. Represents an aryl group such as a phenyl group and a naphthyl group, and n represents an integer of 1 to 10. )
[0031]
Embedded image

[0032]
(Where R²¹And R²²Has a hydrogen atom, an optionally substituted methyl group, an ethyl group, an alkyl group such as propyl and butyl group, an optionally substituted benzyl group and an aralkyl group such as a phenethyl group or a substituent. And an aryl group such as a phenyl group and a naphthyl group, wherein n represents an integer of 0 to 10 or less. )
In addition, R in the above general formulas (5) and (6)¹⁹, R²⁰, R²¹And R²²May have a halogen atom such as fluorine, chlorine, bromine and iodine, a methyl group and an ethyl group. Alkyl groups such as propyl group and butyl group, alkoxy groups such as methoxy group, ethoxy group and propoxy group, aryloxy groups such as phenoxy group and naphthoxy group, benzyl group, phenethyl group, naphthylmethyl group, furfuryl group and thienyl group And an aryl group such as a phenyl group, a naphthyl group, an anthryl group and a pyrenyl group.
[0033]
Further, among the above general formulas (4) to (6), particularly preferable chain polymerizable functional groups include those represented by the following general formulas (7) to (13).
[0034]
Embedded image

[0035]
Further, among the above formulas (7) to (13), the acryloyloxy group of (7) and the methacryloyloxy group of (8) are particularly preferable from the viewpoint of polymerization characteristics and the like.
[0036]
In the present invention, "an electron transporting compound having a chain polymerizable functional group" refers to a compound in which the chain polymerizable group described above is chemically bonded to at least two of the electron transporting compounds described above as a functional group. Is shown. In this case, all of the chain polymerizable functional groups may be the same or different.
[0037]
The electron transporting compound having at least two chain polymerizable functional groups is preferably a compound represented by the following general formula (1).
[0038]
Embedded image

[0039]
Wherein A represents an electron transporting group;¹And P²Represents a chain polymerizable functional group;¹And P²May be the same or different; Z represents an organic group which may have a substituent; a, b and d each represent an integer of 0 or more; a + b × d represents an integer of 2 or more; Is greater than or equal to 2¹May be the same or different, and when d is 2 or more, P²May be the same or different, and when b is 2 or more, Z and P²May be the same or different.
[0040]
Note that here, "a is 2 or more, P¹May be the same or different. "Means that n different types of chain polymerizable functional groups¹¹, P¹², P^Thirteen, P¹⁴, P^Fifteen.... P¹ⁿWhen, for example, when a = 3, the polymerizable functional group P directly bonded to the electron transporting compound A¹Are the same, but two are the same and one is different (for example, P¹¹And P¹¹And P¹²), But each of the three is different (for example, P¹²And P^FifteenAnd P¹⁷) Is acceptable (“P if dＰ is 2 or more, P²May be the same or different ", and" when b is 2 or more, Z may be the same or different "means the same.)
[0041]
The electron transport compound having two or more chain polymerizable functional groups of the general formula (1) has a reduction potential (corresponding to the electron affinity Ea) of -0.2 (v) with respect to the reference electrode SCE (saturated carmelo electrode). ) To -1.2 (v), particularly preferably -0.2 (v) to -0.8 (v).
[0042]
This is because when the reduction potential exceeds -1.2 (v), injection of charges (electrons) from the charge generating material is unlikely to occur, and there are problems such as an increase in residual potential, deterioration in sensitivity, and a large potential fluctuation during repeated use. This is because if it is less than -0.2 (v), problems such as a decrease in charging ability are likely to occur.
[0043]
In addition, the reduction potential described here is measured by the following method.
[0044]
(Method of measuring reduction potential)
A saturated calomel electrode was used as a reference electrode, and 0.1N (n-C₄H₉)₄N⁺ClO₄ ⁻Using a dichloromethane solution, the potential applied to the working electrode (platinum) was swept by a potential sweeper using a potential sweeper, and the potential obtained when the obtained current-potential curve showed a peak was defined as the oxidation potential. More specifically, the sample is 0.1N (n-C₄H₉)₄N⁺ClO₄ ⁻Dissolve in a dichloromethane solution to a concentration of about 1 mmol%. Then, a voltage is applied to this sample solution by the working electrode, and the voltage is linearly changed from 0 (v) to −1.5 (v) (the peak-top position where the current value shows a peak in this current-potential curve). Potential of E₁) Further, the current change when linearly changing from -1.5 (v) to 0 (v) is measured (the potential at the peak top position where the current value shows a peak in this current-potential curve is calculated). E₂) Obtain a current-potential curve. This obtained E₁+ E₂/ 2 was defined as the reduction potential here. When there are a plurality of peaks, the first reduction peak closest to 0 (v) is set to E₁And E₂did.
[0045]
P of A in the above general formula (1)¹Preferred examples of the electron transporting compound in which the bonding site with Z and Z are replaced by a hydrogen atom include the following general formulas (A-1) to (A-11), but are not limited to these compounds.
[0046]
Embedded image

[0047]
Where R¹, R²Represents a hydrogen atom, a methyl group or an ethyl group which may have a substituent. An alkyl group having 10 or less carbon atoms such as a propyl group and a butyl group, a benzyl group which may have a substituent, an aralkyl group such as a phenethyl group, a naphthylmethyl group, a furfuryl group and a thienyl group, which may have a substituent. Aryl groups such as phenyl, naphthyl, anthryl, phenanthryl, pyrenyl, thiophenyl, furyl, pyridyl, quinolyl, benzoquinolyl, carbazolyl, phenothiazinyl, benzofuryl, and benzothiophenyl , An alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, an aryloxy group such as a phenoxy group, a naphthoxy group, an acyl group, an ester group, a cyano group, a nitro group, an amide group, a sulfonic acid group, and a sulfonic acid ester Group, sulfonamide group, hydroxy group, aldehyde group or Indicates Gen atom, an m ≧ 0, n ≧ 0, provided that when m ≧ 2 R¹May be different from each other, and when n ≧ 2, R²May be different from each other.
[0048]
R³, R⁴Represents a methyl group or an ethyl group which may have a substituent. An alkyl group having 10 or less carbon atoms such as a propyl group and a butyl group, a benzyl group which may have a substituent, an aralkyl group such as a phenethyl group, a naphthylmethyl group, a furfuryl group and a thienyl group, which may have a substituent. Aryl groups such as phenyl, naphthyl, anthryl, phenanthryl, pyrenyl, thiophenyl, furyl, pyridyl, quinolyl, benzoquinolyl, carbazolyl, phenothiazinyl, benzofuryl, and benzothiophenyl Or an ester group.
[0049]
Q₁Ｑ, Q₂Is independently oxygen, sulfur, C (CN)₂ＣＲ, CR⁵CN, CY₂(Y is a halogen atom such as fluorine, chlorine and bromine), C (COOR⁶)₂ＣＲ, CR⁷COOR⁸ , NR⁹ Or NCN. Q₃Is an oxygen atom, a sulfur atom or SO₂Is shown.
[0050]
Where R⁵, R⁶, R⁷, R⁸, R⁹Each independently represents a hydrogen atom, a methyl group or an ethyl group which may have a substituent. An alkyl group having 10 or less carbon atoms such as a propyl group and a butyl group, a benzyl group which may have a substituent, a phenethyl group, a naphthylmethyl group, a furfuryl group and a thienyl group may have an aralkyl group or a substituent. Aryl groups such as phenyl, naphthyl, anthryl, phenanthryl, pyrenyl, thiophenyl, furyl, pyridyl, quinolyl, benzoquinolyl, carbazolyl, phenothiazinyl, benzofuryl, and benzothiophenyl Is shown.
[0051]
Embedded image

[0052]
Represents an optionally substituted aryl group such as a benzene ring, a naphthalene ring, an anthracene ring, a thiophene ring, a furan ring, and a pyridine ring.
[0053]
Z in the general formula (1) is an alkylene group which may have a substituent, an arylene group which may have a substituent, CR¹⁰= CR¹¹(R¹⁰And R¹¹Represents an alkyl group, an aryl group or a hydrogen atom;¹⁰And R¹¹May be the same or different), C = O, S = O, SO₂, An organic group which is one or more optionally combined from an oxygen atom or a sulfur atom. Among them, a compound represented by the following general formula (2) is preferable, and a compound represented by the following general formula (3) is particularly preferable.
[0054]
Embedded image

[0055]
In the general formula (3), X¹~ X³Is an alkylene group having 20 or less carbon atoms such as a methylene group, an ethylene group and a propylene group which may have a substituent;¹²= CR^Thirteen) M², C = O, S = O, SO₂Represents an oxygen atom or a sulfur atom;¹And Ar²Is a divalent arylene group which may have a substituent (benzene, naphthalene, anthracene, phenanthrene, pyrene, thiophene, furan, pyridine, quinoline, benzoquinoline, carbazole, phenothiazine, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, etc. From which two hydrogen atoms have been removed). R¹²And R^ThirteenRepresents an alkyl group such as methyl group, ethyl group propyl group and butyl group which may have a substituent, an aryl group such as phenyl group, naphthyl group and thiophenyl group which may have a substituent, or a hydrogen atom. And R¹²And R^ThirteenMay be the same or different. m²Represents an integer of 1 to 5, and p to t represents an integer of 0 to 10 (however, p to t are not simultaneously 0).
[0056]
In the general formula (3), X⁴And X⁵Is (CH₂) M³, (CH = CR¹⁴) M⁴, C = O, or an oxygen atom;³Is a divalent arylene group which may have a substituent (benzene, naphthalene, anthracene, phenanthrene, pyrene, thiophene, furan, pyridine, quinoline, benzoquinoline, carbazole, phenothiazine, benzofuran, benzothiophene, dibenzofuran, dibenzothiophene, etc. From which two hydrogen atoms have been removed). R¹⁴Represents an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group which may have a substituent, an aryl group such as a phenyl group, a naphthyl group and a thiophenyl group which may have a substituent, or a hydrogen atom. . m³Is an integer from 1 to 10, m⁴Represents an integer of 1 to 5, and u to w represent an integer of 0 to 10 (particularly preferably an integer of 0 to 5; however, u to w are not simultaneously 0).
[0057]
In addition, R of the above general formulas (1) to (13) and (A-1) to (A-11)¹~ R²², Ar¹~ Ar³, X¹~ X⁵, Z and Q may have a halogen atom such as fluorine, chlorine, bromine and iodine, a nitro group, a cyano group, a hydroxyl group, a methyl group and an ethyl group. Alkyl groups such as propyl group and butyl group, alkoxy groups such as methoxy group, ethoxy group and propoxy group, aryloxy groups such as phenoxy group and naphthoxy group, benzyl group, phenethyl group, naphthylmethyl group, furfuryl group and thienyl group And an aryl group such as a phenyl group, a naphthyl group, an anthryl group and a pyrenyl group.
[0058]
Further, the electron transporting compound having a chain polymerizable functional group has an electron transporting ability of 1 × 10^-7(Cm²/ V. sec) or more having a drift mobility of at least (provided electric field: 5 × 10⁴v / cm). 1 × 10^-7(Cm²/ V. If the time is less than (sec), electrons may not move sufficiently before development after exposure as an electrophotographic photoreceptor, so that apparently sensitivity may decrease and a residual potential may increase.
[0059]
Hereinafter, typical examples of the electron transporting compound having a chain polymerizable functional group according to the present invention will be described, but the present invention is not limited thereto.
[0060]
[Table 3]

[0061]
[Table 4]

[0062]
[Table 5]

[0063]
In the present invention, by polymerizing and curing an electron transporting compound having two or more chain polymerizable functional groups in the same molecule, in the photosensitive layer, at least two or more compounds having electron transporting ability are provided. Is incorporated into the three-dimensional crosslinked structure via a covalent bond. The electron transporting compound can be polymerized or cross-linked alone, or can be mixed with a compound having another chain polymerizable group, and the type / ratio thereof is arbitrary. The compound having another chain polymerizable group as referred to herein includes both monomers and oligomers / polymers having a chain polymerizable group. When the functional group of the electron transporting compound and the functional group of the other chain polymerizable compound are the same group or a group that can be polymerized with each other, both may form a copolymerized three-dimensional cross-linked structure via a covalent bond. It is possible. When both functional groups are functional groups that do not polymerize with each other, the photosensitive layer may be a mixture of at least two or more three-dimensional cured products or a three-dimensional cured product of the main component containing another chain polymerizable compound monomer or Although it is configured as containing the cured product, it is also possible to form an IPN (Inter Penetrating Network), that is, an interpenetrating network structure, by properly controlling the mixing ratio / film forming method.
[0064]
Further, the photosensitive layer may be formed from the above-mentioned electron transporting compound and a monomer or oligomer / polymer having no chain polymerizable group or a monomer or oligomer / polymer having a polymerizable group other than chain polymerizable group.
[0065]
Further, in some cases, it is possible to contain an electron transporting compound that is not chemically bonded to the three-dimensional crosslinked structure, that is, has no chain polymerizable functional group.
[0066]
Further, it may contain other various additives, Teflon (registered trademark) and other lubricants.
[0067]
The configuration of the photoreceptor of the present invention has a configuration in which a charge generation layer containing a charge generation substance and a charge transport layer containing a charge transport substance are stacked in this order as a photosensitive layer on a conductive support, or a configuration in which the charge transport layer is stacked in reverse order. In addition, any structure of a single layer in which a charge generation material and a charge transport material are dispersed in the same layer can be adopted. In the former laminated type, the charge transport layer may have two or more layers, and in the latter single layer type, a charge transport layer may be further formed on the photosensitive layer containing the same charge generating substance and charge transporting substance. Further, a protective layer can be formed on the charge generation layer or the charge transport layer. In any of these cases, it is sufficient that the photosensitive layer contains a polymerized and cured electron transporting compound having a chain polymerizable group and / or a pre-electron transporting compound. However, from the viewpoint of the characteristics as an electrophotographic photoreceptor, in particular, electric characteristics such as residual potential and durability, a function-separated type photoreceptor having a charge generation layer / a charge transport layer laminated in this order is preferable. An advantage is that the durability of the surface layer can be increased without lowering the charge transporting ability.
[0068]
Next, a method for producing an electrophotographic photosensitive member according to the present invention will be specifically described.
[0069]
The support of the electrophotographic photoreceptor may be any conductive material, for example, a metal or alloy such as aluminum, copper, chromium, nickel, zinc, and stainless steel formed into a drum or sheet, aluminum and copper, and the like. Metal foil laminated on a plastic film, aluminum, indium oxide, tin oxide, etc. deposited on a plastic film, a conductive material applied alone or with a binder resin to provide a conductive layer, or a plastic film And paper.
[0070]
In the present invention, an undercoat layer having a barrier function and an adhesive function can be provided on the conductive support.
[0071]
The undercoat layer is used to improve the adhesion of the photosensitive layer, improve coating properties, protect the support, cover defects on the support, improve charge injection from the support, and protect the photosensitive layer against electrical breakdown. Formed. Examples of the material for the undercoat layer include polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, N-methoxymethylated 6 nylon, copolymer nylon, glue and gelatin. Has been done. These are dissolved in a suitable solvent and applied onto a support. The thickness at this time is preferably 0.1 to 2 μm.
[0072]
When the photoreceptor of the invention is a function-separated type photoreceptor, a charge generation layer and a charge transport layer are laminated. Examples of the charge generation material used in the charge generation layer include selenium-tellurium, pyrylium, thiapyrylium dyes, and various kinds of central metals and crystal systems, specifically, for example, α, β, γ, ε, and X-type crystal forms. Phthalocyanine compounds, anthantrone pigments, dibenzopyrene quinone pigments, pyranthrone pigments, trisazo pigments, disazo pigments, monoazo pigments, indigo pigments, quinacridone pigments, asymmetric quinocyanine pigments, quinocyanines and amorphous silicones.
[0073]
In the case of a function-separated type photoreceptor, the charge generation layer is formed by mixing the charge generation substance with a binder resin and a solvent in an amount of 0.3 to 4 times as much as a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor and a roll mill. It is formed by dispersing well by a method, applying a dispersion, and drying, or formed as a film of a single composition such as a vapor-deposited film of the charge generating substance. The film thickness is preferably 5 μm or less, particularly preferably in the range of 0.1 to 2 μm.
[0074]
Examples of using a binder resin include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylates, methacrylates, vinylidene fluoride, trifluoroethylene, polyvinyl alcohol, and polyvinyl alcohol. Examples include acetal, polycarbonate, polyester, polysulfone, polyphenylene oxide, polyurethane, cellulose resin, phenol resin, melamine resin, silicon resin, epoxy resin, and the like.
[0075]
The electron transporting compound having a chain polymerizable functional group in the present invention is formed as a charge transporting layer on the above-described charge generating layer, or a charge transporting layer comprising a charge transporting substance and a binder resin on the charge generating layer. It can be used later as a surface protective layer having an electron transporting ability. In any case, the method for forming the surface layer generally involves a polymerization / curing reaction after the application of the solution containing the hole transporting compound. Is reacted to obtain a cured product, and then the surface layer can be formed using a material that is dispersed or dissolved again in a solvent. As a method of applying these solutions, for example, a dip coating method, a spray coating method, a curtain coating method, a spin coating method, and the like are known, but a dip coating method is preferable in terms of efficiency / productivity.
[0076]
In addition, deposition, plasma, and other known film forming methods can be appropriately selected.
[0077]
In the present invention, the electron transporting compound having a chain polymerizable group is preferably polymerized and cured by radiation. The greatest advantage of polymerization by radiation is that no polymerization initiator is required, which makes it possible to produce a very high-purity three-dimensional photosensitive layer matrix, and ensures good electrophotographic properties. In addition, the productivity is high due to the short and efficient polymerization reaction, and the good radiation permeability prevents curing when the film is thick or when a shielding substance such as an additive is present in the film. Is very small. However, depending on the type of the chain polymerizable group and the type of the central skeleton, the polymerization reaction may not easily proceed, and in that case, the polymerization initiator can be added within a range that does not affect the polymerization reaction. The radiation used at this time is an electron beam and γ-ray. When irradiating with an electron beam, any type of accelerator such as a scanning type, an electro curtain type, a broad beam type, a pulse type, and a laminar type can be used. When irradiating with an electron beam, irradiation conditions are very important for the photoreceptor of the present invention to develop electrical characteristics and durability. In the present invention, the acceleration voltage is preferably 250 KV or less, and most preferably 150 KV or less. The irradiation dose is preferably in the range of 1 Mrad to 100 Mrad, more preferably in the range of 3 Mrad to 50 Mrad. If the accelerating voltage exceeds the above, the damage of the electron beam irradiation to the photoconductor characteristics tends to increase. If the irradiation dose is smaller than the above range, curing tends to be insufficient, and if the irradiation dose is large, the characteristics of the photoreceptor are likely to deteriorate.
[0078]
When the electron transporting compound having a chain polymerizable group is used as the charge transporting layer, the amount of the electron transporting compound is calculated by the above formula (1) based on the total weight of the charge transporting layer film after polymerization and curing. It is desirable that the hydrogenated product of the electron transporting group A having the chain polymerizable functional group shown is contained in an amount of 20% or more, preferably 40% or more in terms of molecular weight. If it is less than that, the charge transporting ability is reduced, and problems such as a decrease in sensitivity and an increase in residual potential occur. In this case, the film thickness of the charge transport layer is preferably from 1 to 50 μm, particularly preferably from 3 to 30 μm.
[0079]
When the electron transporting compound is used as a surface protective layer on the charge generating layer / charge transporting layer, the underlying charge transporting layer may be a suitable electron transporting compound such as a benzoquinone derivative, a diphenoquinone derivative, a naphthoquinone derivative, a cyclopentadiene derivative, A low-molecular compound such as an indenone derivative, a benzoxazole derivative, a benzothiazole derivative, an imide derivative, a diimide derivative, a 4-oxothiopyran-1,1-dioxide derivative, or a fluorenone derivative is appropriately bound with a suitable binder resin (the above-described resin for the charge generation layer). And a solution dispersed / dissolved in a solvent and coated and dried by the above-mentioned known method. In this case, the ratio of the charge transporting material to the binder resin is desirably 30 to 100, preferably 50 to 100, assuming that the total weight of both is 100. If the amount of the charge transporting substance is less than that, the charge transporting ability is reduced, causing problems such as a decrease in sensitivity and an increase in residual potential. The thickness of the charge transport layer is determined so that the total thickness including the upper surface protective layer is 1 to 50 μm, and is preferably adjusted in the range of 5 to 30 μm.
[0080]
In any of the cases described above, in the present invention, the photosensitive layer containing the cured product of the electron transporting compound having a chain polymerizable group can contain the electron transporting compound.
[0081]
In the case of a single-layer type photosensitive layer, a charge-generating substance is simultaneously contained in the solution containing the electron-transporting compound, and the solution may be provided with a suitable undercoat layer or an intermediate layer. The electron transporting compound is formed on a single-layered photosensitive layer composed of a charge generating substance and a charge transporting substance provided on a conductive support, in the case of being formed by applying and polymerizing / curing after coating on the conductive support. Any of polymerization and curing after application of the solution is possible.
[0082]
Various additives can be added to the photosensitive layer in the invention. The additives include a deterioration inhibitor such as an antioxidant and an ultraviolet absorber, and a lubricant such as tetrafluoroethylene resin particles and carbon fluoride.
[0083]
FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention. In the drawing, reference numeral 1 denotes an electrophotographic photosensitive member of the present invention on a drum, which is rotated at a predetermined peripheral speed in the direction of an arrow with the shaft 2 stopped. In the rotation process, the photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by the primary charging means 3, and then an image from an image exposure means (not shown) such as slit exposure or laser beam scanning exposure. The exposure light 4 is received. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1. The formed electrostatic latent image is then subjected to toner development by the developing unit 5, and the developed toner developed image is transferred between the photoconductor 1 and the transfer unit 6 by a rotation of the photoconductor 1 from a feeding unit (not shown). The transfer material 6 is sequentially transferred to the transfer material 7 taken out and fed synchronously. The transfer material 7 having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing, thereby being printed out of the apparatus as a copy. The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the untransferred toner by a cleaning unit 9, and further subjected to an auxiliary treatment by a pre-exposure light 10 from a pre-exposure unit (not shown). Used repeatedly for image formation. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required. In the present invention, a plurality of components such as the electrophotographic photosensitive member 1, the primary charging unit 3, the developing unit 5, and the cleaning unit 9 are integrally connected as a process cartridge. It may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5 and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, which can be attached to and detached from the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. The process cartridge 11 can be used. When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 reads reflected light or transmitted light from the original, or reads the original with a sensor and converts it into a signal, and scans the laser beam with the signal. , Light emitted by driving an LED array, driving a liquid crystal shutter array, and the like.
[0084]
The electrophotographic photoreceptor of the present invention can be widely used not only for electrophotographic copying machines but also for electrophotographic applications such as laser beam printers, CRT printers, LED printers, liquid crystal printers, and laser plate making.
[0085]
【Example】
(Example 1)
First, the paint for the conductive layer was prepared in the following procedure. 50 parts (parts by mass, hereinafter the same) of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide, 25 parts of phenol resin, 20 parts of methyl cellosolve, 5 parts of methanol, and silicone oil (polydimethylsiloxane poly) 0.002 parts of an oxyalkylene copolymer (average molecular weight: 3000) was dispersed and adjusted by a sand mill containing φ1 mm glass beads for 2 hours. This coating material was applied on a 30φ aluminum cylinder by a dip coating method, and dried at 140 ° C. for 30 minutes to form a conductive layer having a thickness of 20 μm.
[0086]
Next, 5 parts of N-methoxymethylated nylon was dissolved in 95 parts of methanol to prepare a coating for the intermediate layer. This paint was applied on the conductive layer by a dip coating method and dried at 100 ° C. for 20 minutes to form a 0.6 μm intermediate layer.
[0087]
Next, 4 parts of a hydroxygallium phthalocyanine compound having a crystal form having strong peaks at 7.4 ° and 28.2 ° at Bragg angles 2θ ± 0.2 ° in X-ray diffraction of CuKα and polyvinyl butyral resin (butyralization degree of 65 mol) %, Number average molecular weight 35000) 2 parts to 80 parts of cyclohexanone, dispersed with glass beads by a sand mill for 4 hours, diluted with 80 parts of ethyl acetate, and dried on the intermediate layer to obtain a film thickness. Was applied by dip coating to form a charge generation layer.
[0088]
Then, Compound Example Nos. The electron transporting compound of No. 19 was dissolved in a mixed solvent of 30 parts of monochlorobenzene and 30 parts of dichloromethane to prepare a coating material for the charge transport layer. This coating material was coated on the above-mentioned charge generation layer, and heated at 50 ° C. After drying for 10 minutes, the resin was cured by irradiating an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 10 Mrad to form a charge transport layer having a thickness of 15 μm to obtain an electrophotographic photosensitive member.
[0089]
The produced electrophotographic photoreceptor was evaluated for its sedimentability over time, electrophotographic properties, and durability. With respect to the sedimentability with time, a urethane rubber cleaning blade for copying was pressed against the surface of the photoreceptor, stored at 75 ° C., and an accelerated test for the sedimentability was performed. After 14 days, the surface of the photoreceptor was observed under a microscope to determine the presence or absence of precipitation. If there was no precipitation, the test was continued until 30 days later. The electrophotographic characteristics and durability were evaluated by mounting this photoreceptor on a machine obtained by modifying GP55 manufactured by Canon Inc. for positive charging. Initial photoconductor characteristics [dark portion potential Vd, light attenuation sensitivity (light amount required to attenuate light to +200 V at dark portion potential +700 V setting) and residual potential Vsl (potential when irradiating 10 times the light attenuation sensitivity light amount) )], A 15,000-sheet paper-pass durability test is conducted, the occurrence of image defects is visually observed, the amount of scraping of the photoconductor and the photoconductor characteristics after the durability are measured, and each change value ΔVd is measured. , ΔVl (the amount of change in Vl when the same amount of light as that at which Vl becomes +200 V initially was irradiated after the endurance) and ΔVsl.
[0090]
The results are shown in Table 6, where no precipitation occurred in the photoreceptor of the present invention, the photoreceptor characteristics were good, the amount of scraping during durability was small, and the photoreceptor characteristics showed little change in durability. It shows very stable and good properties.
[0091]
(Examples 2 to 16)
The electron transporting compound No. An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1, except that 19 was changed to the compounds shown in Table 6. Table 6 shows the results.
[0092]
(Example 17)
In Example 1, the electron transporting compound No. Same as Example 1 except that the amount of 19 was 48 parts and further 12 parts of an acrylate monomer having the following formula was added.
[0093]
Embedded image

[0094]
An electrophotographic photoreceptor was prepared and evaluated. Table 6 shows the results.
[0095]
(Examples 18 to 21)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the irradiation conditions of the electron beam in Example 1 were changed as shown in Table 6. Although the shaving amount and the durability image were good, the sensitivity was slightly lowered and the residual potential was slightly increased in the initial electrophotographic characteristics by increasing the irradiation dose. Table 6 shows the results.
[0096]
(Example 22)
After forming a conductive layer, an intermediate layer and a charge generation layer in the same manner as in Example 1, the electron transporting compound No. 1 shown in Table 3 was used. 14 60 parts and 0.6 parts of a photopolymerization initiator having the following structural formula are mixed in a mixed solvent of 30 parts of monochlorobenzene and 30 parts of dichloromethane.
[0097]
Embedded image

[0098]
After dissolving and preparing a coating material for the charge transport layer, this coating material was coated on the above-mentioned charge generation layer, and then 500 mW / cm using a metal halide lamp.²A 15 μm-thick charge transporting layer was formed by curing at a light intensity of 1. to obtain an electrophotographic photosensitive member. The obtained photoreceptor was evaluated in the same manner as in Example 1. Table 6 shows the results.
[0099]
(Example 23)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the photopolymerization initiator in Example 22 was changed to the following thermal polymerization initiator and the curing reaction was changed to 150 ° C./1 hour instead of the ultraviolet curing. Table 6 shows the results.
[0100]
Embedded image

[0101]
(Example 24)
After forming a conductive layer and an intermediate layer in the same manner as in Example 1, 20 parts of a hole transporting compound having the following structural formula and a polycarbonate resin (Z type; weight average molecular weight:
[0102]
Embedded image

[0103]
(50000) was dissolved in a mixed solvent of 50 parts of monochlorobenzene and 20 parts of dichloromethane to prepare a charge transport layer on the intermediate layer using a paint for a charge transport layer. At this time, the thickness of the charge transport layer was 10 μm. Next, the charge generation paint used in Example 1 was applied by a dip coating method so that the film thickness after drying was 2.0 μm to form a charge generation layer.
[0104]
Next, the electron transporting compound No. 60 to 60 parts were dissolved in a mixed solvent of 50 parts of monochlorobenzene and 30 parts of dichloromethane to prepare a coating for the surface protective layer. The paint was applied on the charge transport layer by spray coating, dried at 50 ° C. for 10 minutes, and then irradiated with an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 10 Mrad to cure the resin, and the film thickness was 5 μm. Was formed to obtain an electrophotographic photosensitive member. This photoreceptor was evaluated in the same manner as in Example 1. Table 6 shows the results.
[0105]
(Example 25)
After forming a conductive layer, an intermediate layer and a charge generation layer in the same manner as in Example 1, 4 parts each of a naphthalenetetracarboxylic diimide derivative compound having the following structural formula was used.
[0106]
Embedded image

[0107]
And 10 parts of a polycarbonate resin (Z type; weight average molecular weight: 50,000) dissolved in a mixed solvent of 50 parts of monochlorobenzene and 20 parts of dichloromethane to prepare a charge transport layer coating material, and the charge on the charge generation layer was adjusted. A transport layer was formed. At this time, the thickness of the charge transport layer was 15 μm. Then, the electron transporting compound example No. 19 to 60 parts was dissolved in a mixed solvent of 50 parts of monochlorobenzene and 30 parts of dichloromethane to prepare a paint for a surface protective layer. The paint was applied on the charge transport layer by spray coating, dried at 50 ° C. for 10 minutes, and then irradiated with an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 10 Mrad to cure the resin, and the film thickness was 5 μm. Was formed to obtain an electrophotographic photosensitive member. This photoreceptor was evaluated in the same manner as in Example 1. Table 6 shows the results.
[0108]
(Example 26)
After forming a conductive layer and an intermediate layer in the same manner as in Example 1, 3 parts of β-type oxytitanium phthalocyanine crystal, 40 parts of a compound of the following structural formula (A) as a hole transport material, and the following structural formula ( 40 parts of the compound of B),
[0109]
Embedded image

[0110]
A coating of a single-layer photoreceptor in which 100 parts of a polycarbonate resin (Z type; weight average molecular weight: 50,000) and 700 parts of tetrahydrofuran were mixed and dispersed by a ball mill was applied, and a photosensitive layer having a dried film thickness of 13 μm was formed. Next, the electron transporting compound Nos. 32 to 60 parts was dissolved in a mixed solvent of 50 parts of monochlorobenzene and 30 parts of dichloromethane to prepare a paint for a surface protective layer. The paint was applied on the charge transport layer by spray coating, dried at 50 ° C. for 10 minutes, and then irradiated with an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 10 Mrad to cure the resin, and the film thickness was 5 μm. Was formed to obtain an electrophotographic photosensitive member. This photoreceptor was evaluated in the same manner as in Example 1. Table 6 shows the results.
[0111]
[Table 6]

[0112]
(Comparative Example 1)
After forming a conductive layer, an intermediate layer and a charge generation layer in Example 1, 15 parts of an electron transporting compound having the following structural formula and 15 parts of a polymethyl methacrylate resin (number average molecular weight: about 40,000) were mixed with 50 parts of monochlorobenzene and dichloromethane. A charge transport layer was formed on the charge generation layer using a charge transport layer coating solution prepared and dissolved in 20 parts of a mixed solvent. At this time, the thickness of the charge transport layer was 15 μm.
[0113]
Embedded image

[0114]
As a result of evaluating this electrophotographic photosensitive member in the same manner as in Example 1, precipitation was observed after 14 days. On the other hand, the electrophotographic characteristics in the initial stage were good, but the amount of surface layer shaved in durability was large, and image defects such as fogging and scratches occurred. Further, after 8000 sheets were scraped, the thickness of the charge transport layer became thinner, and charging failure occurred, making image formation impossible. Table 7 shows the results.
[0115]
(Comparative Example 2)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Comparative Example 1 except that a polycarbonate resin (Z type; weight average molecular weight: 50,000) was used instead of the polymethyl methacrylate resin in Comparative Example 1. In the precipitation test, precipitation was observed after 14 days. In addition, although the durability was slightly improved as compared with the case of the polymethyl methacrylate resin, it was not sufficient, and charging failure occurred from 12,000 sheets, making image formation impossible. Table 7 shows the results.
[0116]
(Comparative Example 3)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Comparative Example 2 except that the electron transporting compound of Comparative Example 2 was changed to 10 parts and the polycarbonate resin was changed to 15 parts. As a result, although the durability was improved as compared with Comparative Example 2, As the distance between the charge transporting substances was increased, the charge transporting ability was reduced, and a decrease in sensitivity and an increase in residual potential were observed. Table 7 shows the results.
[0117]
(Comparative Example 4)
A photoconductor was prepared and evaluated in the same manner as in Example 24 except that the protective layer was not formed. Insufficiency of charging and fogging occurred from the beginning, and the image became less worthy of image formation evaluation than 500 sheets. Table 7 shows the results.
[0118]
(Comparative Example 5)
A photoconductor was prepared and evaluated in the same manner as in Example 25, except that the protective layer was not formed. In the precipitation test, precipitation was observed after 30 days. The durability was not sufficient, and charging failure occurred from 13,000 sheets, making image formation impossible. Table 7 shows the results.
[0119]
(Comparative Example 6)
A photoconductor was prepared and evaluated in the same manner as in Example 26 except that the protective layer was not formed. The durability was not sufficient, and poor charging and fogging occurred on 800 sheets, and image formation was impossible due to poor charging on 5000 sheets. Table 7 shows the results.
[0120]
(Comparative Example 7)
After forming a conductive layer, an intermediate layer, a charge generation layer, and a charge transport layer in the same manner as in Example 25, 50 parts of an acrylic monomer having the following structural formula was added to 50 parts of tetrahydrofuran.
[0121]
Embedded image

[0122]
To prepare a coating for the surface protective layer. This paint was applied on the charge transport layer by spray coating, dried at 50 ° C. for 10 minutes, and then irradiated with an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 30 Mrad to cure the resin, and the film thickness was 5 μm. Was formed to obtain an electrophotographic photosensitive member. This photoreceptor was evaluated in the same manner as in Example 1. The residual potential was higher than at the beginning, and it was not possible to evaluate image formation and potential fluctuation. Table 7 shows the results.
[0123]
(Comparative Example 8)
The following electron-transporting polymer was synthesized by the same method as disclosed in JP-A-09-194535 (weight average molecular weight: 10,000, reduction potential: -0.93０．９v
)Obtained.
[0124]
Embedded image

[0125]
After forming the conductive layer, the intermediate layer, and the charge generation layer in Example 1, 10 parts of the polymer was dissolved in a mixed solvent of 40 parts of monochlorobenzene and 10 parts of dichloromethane, and a coating material for a charge transport layer was prepared. A charge transport layer was formed by dip coating. At this time, the thickness of the charge transport layer was 15 μm. This electrophotographic photosensitive member was evaluated in the same manner as in Example 1. The initial potential characteristics and the durability potential characteristics were not sufficient, and scratches and fogging occurred in the durability image from 7,000 sheets. Table 7 shows the results.
[0126]
(Comparative Example 9)
0.4 parts of the following compound disclosed in JP-A-11-119458:
[0127]
Embedded image

[0128]
A coating for a protective layer was prepared by mixing 0.5 part of a silicon hard coat material (X-40-2239; manufactured by Shin-Etsu Chemical Co., Ltd.) and 3 parts of n-butyl ether. After forming a conductive layer, an intermediate layer and a charge generation layer in the same manner as in Example 24, this coating material for a protective layer was applied on the charge generation layer by a spray coating method to form a dry surface protection layer at 100 ° C. for 10 minutes. . This electrophotographic photosensitive member was evaluated in the same manner as in Example 1. Although the shaving property was fairly good, the initial potential characteristics and the durable potential characteristics were not sufficient, and fog occurred on the durable image from 1000 sheets. Table 7 shows the results.
[0129]
[Table 7]

[0130]
(Example 27)
On an alumite-treated aluminum cylinder, 3 parts of β-type oxytitanium phthalocyanine crystal, 50 parts of the compound (A) of Example 26 as a hole transport material, and electron transport compound example No. 20 to 50 parts, 30 parts of a polycarbonate resin (Z type; weight average molecular weight: 40000), and 700 parts of tetrahydrofuran were mixed and dispersed in a ball mill by dip coating with a coating of a single-layer photoreceptor, and dried at 50 ° C. for 10 minutes. The resin was cured by irradiating an electron beam under the conditions of an acceleration voltage of 150 KV and an irradiation dose of 10 Mrad to obtain a single-layer type electrophotographic photosensitive member having a thickness of 15 μm. This photoreceptor was attached to a cylinder of a modified machine of a laser beam printer (Laser @ Jet4000: manufactured by Hewlett-Packard), and charging was set so that the initial dark portion potential (Vd) became -700 (V). (Nm) of laser light was applied to reduce the potential of -700 (V) to -200 (V). Furthermore, 20 (μJ / cm²The initial characteristics were measured with the potential when the light amount of (1) was applied as the residual potential (Vr). The result was EΔ500; 0.42 (μJ / cm²), Vr; 90 (v).
[0131]
Further, a good image without image defects was obtained even after continuous running of 2,000 sheets, and the amount of scraping of the drum at the end of 2,000 sheets was 0.4 μm.
[0132]
(Example 28)
Except that the compound of the following structural formula was used instead of the compound (A) of Example 27,
[0133]
Embedded image

[0134]
A photoconductor was prepared in the same manner as in Example 27, and the same evaluation was performed. The result was EΔ500; 0.38 (μJ / cm²), Vr; 75 (v), the scraping amount of the drum at the end of 2,000 sheets was 0.15 μm.
[0135]
(Comparative Example 10)
On an alumite-treated aluminum cylinder, 3 parts of β-type oxytitanium phthalocyanine crystal, 50 parts of the compound (A) of Example 26 as a hole transport material, the following electron transport compound
[0136]
Embedded image

[0137]
A single-layer type electrophotographic photoreceptor having a thickness of 15 μm is obtained by dip-coating a coating of a single-layer type photoreceptor in which 50 parts, 100 parts of a polycarbonate resin (Z type; weight average molecular weight: 40000) and 700 parts of tetrahydrofuran are mixed and dispersed by a ball mill. Got. This photoreceptor was evaluated in the same manner as in Example 27. The result was EΔ500; 0.55 (μJ / cm²), Vr; 110 (v), the scraping amount of the drum at the end of 2,000 sheets was 2.9 μm.
[0138]
【The invention's effect】
The electrophotographic photoreceptor of the present invention has excellent effects on precipitation resistance, abrasion resistance and scratch resistance. Further, the electrophotographic characteristics such as sensitivity and residual potential are very good, and stable performance can be exhibited even when repeatedly used.
[0139]
Further, the effect of the electrophotographic photosensitive member is naturally exerted also in a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member, and high image quality is maintained for a long time.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having a process cartridge having an electrophotographic photosensitive member of the present invention.
[Explanation of symbols]
1. Electrophotographic photoreceptor
2 axis
3 Primary charging means
4 Image exposure light
5 Development means
6 Transfer means
7 transfer material
8 Image fixing means
9 Cleaning means
10 ° pre-exposure light
11 process cartridge
12mm rail

Claims (17)

In an electrophotographic photosensitive member having a photosensitive layer on a conductive support, the outermost surface layer of the photosensitive layer contains a polymerized electron transporting compound having two or more chain polymerizable functional groups in the same molecule. An electrophotographic photosensitive member characterized by the following. The electron transporting compound having a chain polymerizable functional group is represented by the following general formula (1)

(Where A represents an electron transporting group; P ¹ and P ² represent a chain polymerizable functional group; P ¹ and P ² may be the same or different; Z may have a substituent A, b and d each represent 0 or an integer of 1 or more; a + b × d represents an integer of 2 or more; and when a is 2 or more, P ¹ may be the same or different; Is 2 or more, P ² may be the same or different, and when b is 2 or more, Z and P ² may be the same or different.)
The electrophotographic photosensitive member according to claim 1, wherein The value of the reduction potential (corresponding to the electron affinity Ea) of the electron transporting compound having a chain polymerizable functional group represented by the general formula (1) is from -0.2 V to -1 with respect to the reference electrode SCE (saturated carmelo electrode). 3. The electrophotographic photosensitive member according to claim 2, wherein the voltage is 2V. Electron-transporting compounds in which the bonding site of A in formula (1) to P ¹ and Z are replaced by hydrogen atoms are represented by the following formulas (A-1) to (A-11)

[Wherein, R ¹ and R ² represent a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group, and an aryl. An oxy group, an acyl group, an ester group, a cyano group, a nitro group, an amide group, a sulfone group, a sulfonamide group, a hydroxy group, an aldehyde group or a halogen atom, m ≧ 0, n ≧ 0, and m ≧ 2 When R ¹ may be different from each other, and when n ≧ 2, R ² may be different from each other;
R ³ and R ⁴ represent an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aryl group or an ester group which may have a substituent,
Q ₁ and Q ₂ are each independently an oxygen atom, a sulfur atom, C (CN) ₂ , CR ⁵ CN, CY ₂ (Y is a halogen atom), C (COOR ⁶ ) ₂ , CR ⁷ COOR ⁸  , NR ⁹  Or NCN; Q ₃ represents an oxygen atom, a sulfur atom or SO ₂ ;
(However, R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represent a hydrogen atom, an alkyl group optionally having a substituent, an aralkyl group optionally having a substituent, or a substituent. And any of the aryl groups which may be present).

Represents an aryl ring which may have a substituent. ]
The electrophotographic photoreceptor according to claim 2, wherein In the general formula (1), Z is an alkylene group which may have a substituent, an arylene group which may have a substituent, CR ¹⁰ ＣＲCR ¹¹ (R ¹⁰ and R ¹¹ have a substituent. And R ¹⁰ and R ¹¹ may be the same or different.), C ＝ O, S ＝ O, SO ₂ , an oxygen atom or The electrophotographic photoreceptor according to any one of claims 2 to 4, wherein the electrophotographic photoreceptor represents an organic group which is one or arbitrarily combined from a sulfur atom. Z in the above general formula (1) is the following general formula (2)

[Wherein X ^{1 to} X ³ may be the same or different, and each may have an alkylene group which may have a substituent, (CR ¹² = CR ¹³ ) m ¹ , C 、 O, SＳO, SO ₂ , oxygen Represents an atom or a sulfur atom; Ar ¹ and Ar ² represent an arylene group which may have a substituent (R ¹² and R ¹³ each represent an alkyl group which may have a substituent; A good aryl group or a hydrogen atom, and R ¹² and R ¹³ may be the same or different; m ¹ is an integer of 1 to 5, p to t is an integer of 0 or 1 to 10; It cannot be 0 at the same time.) ]
The electrophotographic photosensitive member according to claim 2, wherein Z in the general formula (1) is the following general formula (3)

Wherein Ar ³ represents a divalent arylene group which may have a substituent; X ⁴ and X ⁵ represent (CH ₂ ) m ² , (CH （CR ¹⁴ ) m ³ , C 、 O, or oxygen Represents an atom (R ¹⁴ represents an alkyl group which may have a substituent, an aryl group which may have a substituent or a hydrogen atom; m ² is an integer of 1 to 10, m ³ is an integer of 1 to 5 Integers, u to w each represent 0 or an integer from 1 to 10; provided that u to w are not 0 at the same time.). ]
The electrophotographic photoreceptor according to claim 2, wherein One or both of the chain polymerizable groups P ¹ and P ² are represented by the following formula (4)

[E is a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, a cyano group, a nitro group, an alkoxy group, -COOR ¹⁵ (wherein R ¹⁵ is A hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, and an aryl group which may have a substituent.), CONR ¹⁶ R ¹⁷ (R ¹⁶ , R ¹⁷ are a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, and an aryl group which may have a substituent, May be different.); W is a divalent aryl group which may have a substituent or a divalent alkylene group which may have a substituent, —COO—, —CH ₂ —, -O-,
—CONR ¹⁸ — (wherein, R ¹⁸ is a hydrogen atom, a halogen atom, an alkyl group optionally having a substituent, an aralkyl group optionally having a substituent, or an aryl group optionally having a substituent. F) represents 0 or 1. ]
The electrophotographic photoreceptor according to any one of claims 2 to 7, which is an unsaturated polymerizable functional group represented by the formula: One or both of the chain polymerizable groups P ¹ and P ² are represented by the following formula (5)

(Wherein, R ¹⁹ and R ²⁰ represent a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent; n is It represents an integer of 1 to 10 or less.)
The electrophotographic photoreceptor according to any one of claims 2 to 7, which is a cyclic ether group represented by the formula: One or both of the chain polymerizable groups P ¹ and P ² are represented by the following formula (6)

(Wherein, R ²¹ and R ²² represent a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent; n is 0 or an integer of 1 to 10 or less.)
The electrophotographic photosensitive member according to any one of claims 2 to 7, which is an alicyclic epoxy group represented by the formula: One or both of the chain polymerizable groups P ¹ and P ² are represented by the following formulas (7) to (13)

The electrophotographic photoreceptor according to any one of claims 2 to 7, wherein One or both of the chain polymerizable groups P ¹ and P ² are represented by the following formula (7) or (8)

The electrophotographic photosensitive member according to claim 11, which is any one of the above. The electrophotographic photoreceptor according to claim 1, wherein the polymerization is performed by an electron beam. 14. The electrophotographic photosensitive member according to claim 13, wherein an acceleration voltage of the electron beam is 250 KV or less. 15. The electrophotographic photoreceptor according to claim 13, wherein the dose of the electron beam is 1 to 100 Mrad. 16. The electrophotographic photosensitive member according to claim 1, and at least one unit selected from the group consisting of a charging unit, a developing unit, and a cleaning unit, which are integrally supported and detachably attached to an electrophotographic apparatus main body. A process cartridge. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an image exposing unit, a developing unit, and a transferring unit.

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