JP2004198594A - Electrophotographic photoreceptor, process cartridge, and electrophotographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having superior electrical properties as well as superior mechanical durability, a process cartridge with such an electrophotographic photoreceptor, and an electrophotographic apparatus. <P>SOLUTION: In the electrophotographic photoreceptor having a photosensitive layer on a support and also having a surface layer comprising a resin obtained by curing a compound having a chain-polymerizable functional group by irradiation with an electron beam, a heat capacity per unit area of the support is ≥0.35 J/(cm<SP>2</SP>K) and an electron beam absorbed dose rate in the surface of the object to be irradiated in the irradiation is 1×10<SP>3</SP>-2×10<SP>7</SP>Gy/sec. A process cartridge with such an electrophotographic photoreceptor and an electrophotographic apparatus can be obtained. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００２８】
式中、Ｅは、水素原子、フッ素、塩素及び臭素などのハロゲン原子、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などのアルキル基、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などのアラルキル基、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などのアリール基、メトキシ基、エトキシ基及びプロポキシ基などのアルコキシ基、ＣＮ基、ニトロ基、−ＣＯＯＲ¹またはＣＯＮＲ^２Ｒ^３を示す。
【００２９】
Ｗは、置換基を有してもよい２価のフェニレン、ナフチレン及びアントラセニレンなどのアリーレン基、置換基を有してもよいメチレン、エチレン及びブチレンなどの２価のアルキレン基、−ＣＯＯ−、−ＣＨ_２−、−Ｏ−、−ＯＯ−、−Ｓ−または−ＣＯＮＲ^４−で示される。
【００３０】
Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、水素原子、フッ素、塩素、臭素及びヨウ素などのハロゲン原子、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などのアルキル基、置換基を有してもよいベンジル基及びフェネチル基などのアラルキル基また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などのアリール基を示し、Ｒ^２とＲ^３は互いに同一であっても、異なっていてもよい。また、ｆは、０または１を示す。
【００３１】
Ｅ、Ｗ及びＲ^１〜４が有してもよい置換基としては、フッ素、塩素、臭素及びヨウ素などのハロゲン原子、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などのアルキル基、メトキシ基、エトキシ基及びプロポキシ基などのアルコキシ基、フェノキシ基及びナフトキシ基など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などのアラルキル基またはフェニル基、ナフチル基、アンスリル基及びピレニル基などのアリール基などが挙げられる。
【００３２】
上記式（１）で示される不飽和重合性官能基の好ましい例を以下に示すがこれらに限定されるものではない。
【００３３】
【外２】

【００３４】
上記式中、Ｒ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などのアルキル基、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などのアラルキル基、置換基を有してもよいフェニル基、ナフチル基及びアンスリル基などのアリール基または水素原子を示す。
【００３５】
Ｒが有してもよい置換基としては、フッ素、塩素、臭素及びヨウ素などのハロゲン原子、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などのアルキル基、メトキシ基、エトキシ基及びプロポキシ基などのアルコキシ基、フェノキシ基及びナフトキシ基など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などのアラルキル基またはフェニル基、ナフチル基、アンスリル基及びピレニル基などのアリール基などが挙げられる。
【００３６】
これらの中では、下記式（２）〜（６）で示される基が好ましく、特には式（２）のアクリロイルオキシ基及び式（３）のメタクリロイルオキシ基が重合速度などの面から好ましい。
【００３７】
【外３】

【００３８】
本発明における、式（１）で示される不飽和重合性官能基を有する化合物は、その構造単位の繰り返しにより、モノマーとオリゴマーに大別される。モノマーとは、式（１）で示される不飽和重合性官能基を有する構造単位の繰り返しがなく、比較的分子量の小さいものであり、オリゴマーとは、式（１）で示される不飽和重合性官能基を有する構造単位の繰り返し数が２〜２０程度の重合体である。また、ポリマーまたはオリゴマーの末端のみに式（１）で示される不飽和重合性官能基を有するマクロマーも本発明の電子写真感光体が有する表面層用の化合物として使用可能である。
【００３９】
本発明においては、電子写真感光体の電気的な特性と耐久性の両立という点からモノマーを使用することが好ましい。式（１）で示される不飽和重合性官能基をもつオリゴマーまたはマクロマーを用いる場合も、モノマーと混合して使用することが好ましい。また、上記式（１）で示される不飽和重合性官能基を有するモノマーは一分子中の官能基数によって更に分類が可能であり、一分子に官能基が一つのものは単官能モノマーと呼ばれ、二つ以上の場合には多官能モノマーと呼ばれる。本発明においては、感光体表面層の硬度を十分に確保するために多官能モノマーを使用することが好ましい。
【００４０】
連鎖重合性官能基を有する化合物を溶液状態で用いる場合では、その溶剤としてはトルエン、キシレン及びモノクロルベンゼンなどの芳香族系溶剤のほか、ジオキサン、テトラヒドロフラン、テトラヒドロピラン及びメチルセルソルブなどのエーテル類、メチルエチルケトン及びメチルブチルケトンなどのケトン類、並びにメタノール、エタノール、ブタノール及びプロパノールなどのアルコール類などが使用可能である。
【００４１】
また、本発明における不飽和重合性官能基を有する化合物は、例えば、加藤清視著の「紫外線硬化システム」（平成元年２月２８日発行 総合技術センター出版）の１７７〜１９２頁に記載されているアクリルあるいはメタクリル基を有するオリゴマーや２５９〜３０２頁に記載されているアクリルあるいはメタクリル基を有するモノマーなどが挙げられる。更に、本発明における不飽和重合性官能基を有する化合物としては、電荷輸送機能を併せ持った化合物であることが電子写真感光体の耐久性と電気的特性の両立という点から好ましい。中でも正孔輸送性化合物であることが好ましい。
【００４２】
不飽和重合性官能基を有する正孔輸送性化合物としては、不飽和重合性官能基を有する公知の正孔輸送性化合物や、公知の正孔輸送性化合物の一部に不飽和重合性官能基を付加した化合物などであればよい。電荷輸送物質としては、以後の電荷輸送層の詳細な記載にあるようなヒドラゾン化合物、ピラゾリン化合物及びトリフェニルアミン化合物などであることが好ましいが、特にこれらに限定されるものではなく、正孔輸送機能を有する化合物であれば、いかなる化合物を用いることも可能である。
【００４３】
但し、本発明においては、表面層の硬度を十分に確保するために、不飽和重合性官能基を有し、且つ電荷輸送機能を有する化合物においても、一分子中に複数の不飽和重合性官能基を有することが好ましい。このような化合物の具体例は、例えば特開２００１−１７５０１６号公報などに示されている。
【００４４】
以下の表に不飽和重合性官能基を有する化合物の好ましい例を示すが、本発明はこれらの化合物に限定されるものではない。
【００４５】
【外４】

【００４６】
【外５】

【００４７】
【外６】

【００４８】
【外７】

【００４９】
【外８】

【００５０】
【外９】

【００５１】
これらの中では、化合物例Ｎｏ．（９）、（１１）、（１２）、（１３）、（１７）及び（１９）の化合物が好ましく、特には化合物例Ｎｏ．（９）、（１１）、（１２）及び（１７）の化合物が好ましく、更には化合物例Ｎｏ．（１１）及び（１２）の化合物が好ましく、化合物例Ｎｏ．（１２）の化合物が最も好ましい。
【００５２】
本発明においては、支持体上に感光層を有する電子写真感光体の表面層を、連鎖重合性官能基を有する化合物を電子線照射によって硬化することによって形成する際に、単位面積当たりの熱容量が０．３５Ｊ／ｃｍ^２・Ｋ以上である支持体を用い、且つ該電子線の照射における被照射体表面での電子線吸収線量率を１×１０^３〜２×１０^７Ｇｙ／ｓｅｃとする。
【００５３】
電子線を照射される前の表面層は、前記連鎖重合性官能基を有する化合物を溶解した溶液を、支持体、支持体上に必要に応じて形成された中間層あるいは支持体上または中間層上に形成された電荷発生物質を含有する電荷発生層や電荷輸送物質を含有する電荷輸送層、あるいは電荷発生物質と電荷輸送物質の双方を含有する層といった感光層などの上に塗布後、乾燥することにより形成される。また、前もって連鎖重合性官能基を有する化合物をある程度反応させて得た硬化物を溶剤中に分散または溶解させた溶液を、塗布後、乾燥したものとすることも可能である。
【００５４】
溶液を塗布する方法としては、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及びスピンコーティング法などが挙げられる。
【００５５】
本発明においては、このようにして形成された表面層を有する被照射体に対して、電子線を特定の条件を満足するように照射するのである。
【００５６】
電子線を照射するための加速器としては、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、パルス型及びラミナー型などいずれの形式も使用することができる。
【００５７】
本発明の電子写真感光体を作成する際に用いることができる好ましい電子線照射装置の概略構成の例を図１に示す。
【００５８】
図１に示すように、本発明に用いられる電子線照射装置は、電子線を発生させる電子線発生部１１と、電子写真感光体に電子線を照射する照射室２０、電子線発生部１１及び発生した電子線を照射室２０に導入するための照射窓部３０とを備える。
【００５９】
電子線発生部１１は、電子線を発生するターミナル１２と、ターミナル１２で発生した電子線を真空空間で加速する加速管１４とを有するものである。また、電子線発生部１１の内部は、電子が気体分子と衝突してエネルギーを失うことを防ぐため、図示しない油拡散ポンプなどにより１０^−４〜１０^−６Ｐａの真空に保たれている。
【００６０】
ターミナル１２は、熱電子を放出する線状のフィラメント１２ａと、フィラメント１２ａを備えたガン構造体１２ｂと、フィラメント１２ａで発生した熱電子をコントロールするグリッド１２ｃとを有する。フィラメント１２ａ及びグリッド１２ｃの図面の奥行き方向の長さを、少なくとも被照射体１’の電子線が照射されるべき部分の長手方向の長さよりも長くすれば、被照射体１’の長手方向は１回の電子線照射で全体を照射することができる。
【００６１】
また、電子線発生部１１には、フィラメント１２ａを加熱して熱電子を放出するための不図示の加熱用電源と、フィラメント１２ａとグリッド１２ｃとの間に電圧を印加する同じく不図示の制御用直流電源と、グリッド１２ｃと照射窓部３０に設けられた窓箔３２との間に電圧を印加する加速用直流電源とが設けられている。
【００６２】
照射室２０は、被照射体１’表面に電子線を照射する照射空間２２を含むものである。後述の実施例のように、電子写真感光体の表面層を硬化させる場合には、硬化を安定させるために照射室内部を脱酸素の雰囲気としている。また、被照射体１’は、照射室２０の中をコンベアなどの搬送手段により矢印Ａの方向に搬送され、照射部で電子線が照射される。本発明においては、電子線が照射される際に被照射体１’を回転することが好ましい。照射終了後、被照射体１’は再び矢印Ａの方向に搬送され、外部に搬出される。
【００６３】
電子線発生部１１及び照射室２０の周囲は電子線照射時に二次的に発生するＸ線が外部に漏出しないように、鉛遮蔽されている。
【００６４】
照射窓部３０は、金属箔からなる窓箔３２と、窓箔３２を冷却するとともに窓箔３２を支持する窓枠構造体３４とを有するものである。窓箔３２は、電子線発生部１０内の真空雰囲気と照射室２０内の雰囲気とを仕切り、窓箔３２を介して照射室２０内に電子線を取り出すものである。
【００６５】
加熱用電源によりフィラメント１２ａに電流を流して加熱すると、フィラメント１２ａは熱電子を放出し、この熱電子はフィラメント１２ａとグリッド１２ｃとの間に印加された制御用直流電源の制御電圧によって四方八方に引き寄せられる。このうちグリッド１２ｃを通過したものだけが電子線として有効に取り出される。そして、このグリッド１２ｃから取り出された電子線は、グリッド１２ｃと窓箔３２との間に印加された加速用直流電源の加速電圧により加速管１４内の加速空間で加速された後、照射窓部３０の窓箔３２を突き抜け、照射室２０内を搬送される被照射体１’に照射される。なお、通常は加熱用電源と加速用直流電源とを所定の値に設定し、制御用直流電源を可変にすることで、電子線の電流の調整を可能にしている。
【００６６】
本発明が規定する電子線の照射における被照射体表面での電子線吸収線量率は１×１０^３〜２×１０^７Ｇｙ／ｓｅｃであり、好ましくは１×１０^４〜２×１０^６Ｇｙ／ｓｅｃである。この電子線吸収線量率は、被照射体表面での電子線密度分布において、そのピーク位置が１／ｅ以上であるような有効電子線照射幅内での電子線吸収線量を被照射体表面が有効電子線照射幅内に存在する時間で除したものである。吸収線量は、汎用のフィルム線量計、例えばＦＷＴ−６０（ＦａｒＷｅｓｔ Ｔｅｃｈｎｏｌｏｇｙ社製）により測定することができる（但し、直接測定できる吸収線量は１×１０^５Ｇｙ以下であり、それを超える場合は１×１０^５Ｇｙ以下の吸収線量を測定した時の電流値（あるいは時間）より概算する）。電子線吸収線量率は、電子線の吸収線量、加速電圧、照射時間及び被照射体表面の移動速度などによって制御することができる。
【００６７】
本発明においては、電子線の吸収線量は１×１０^３〜５×１０^５Ｇｙであることが好ましく、更に好ましくは５×１０^３〜３×１０^５Ｇｙが好ましい。吸収線量が１×１０^３Ｇｙに満たないと表面層を十分に硬化しにくくなり、５×１０^５Ｇｙを超えると感度や残留電位の特性が悪化し易くなる。
【００６８】
なお、電子線の吸収線量率及び吸収線量については、上述のように公知の測定手段用いて被照射体表面における値を測定すればよいが、本発明では被照射体表面での吸収線量を必ずしも測定する必要はなく、被照射体への照射線量から被照射体表面における吸収線量を算出することもできる。即ち、被照射体表面における電子線の吸収線量率及び吸収線量は、電子線照射装置の出力調整によって制御することができる。
【００６９】
また、本発明においては、電子線吸収線量率が同じでも、電子線が照射されている時間が短い（電子線吸収線量が大きい）方が好ましい。なぜならば、電子線により生じたラジカルなどの重合あるいは架橋反応に寄与する活性種は、時間が経つにつれて失活してしまうため、反応率が落ちてしまうからである。この現象は、電子線照射時の雰囲気を不活性ガスにすることなどである程度は改善されるが、本発明においては、電子線照射時間が５秒以下であることが好ましく、特には２秒以下であることが好ましい。
【００７０】
また、本発明においては、電子線の加速電圧は５×１０^４〜２×１０^５Ｖであることが好ましい。５×１０^４Ｖに満たないと表面層の硬化が膜厚方向で不均一となり易く、２×１０^５Ｖを超えると電子写真感光体の劣化が生じ易くなる。なお、本発明における加速電圧とは、図１中のタ−ミナル１２と陽極である窓箔３２の間に印加される直流電圧値のことである。
【００７１】
本発明においては、表面層に導電性粒子を含有させることもでき、用いられる導電性粒子としては、金属、金属酸化物及びカーボンブラックなどが挙げられるが、透明性の点で金属酸化物を用いることが特に好ましい。
【００７２】
金属としては、アルミニウム、亜鉛、銅、ニッケル、銀、ステンレス及びこれらの金属をプラスチックの粒子の表面に蒸着したものなどが挙げられる。金属酸化物としては、酸化亜鉛、酸化チタン、酸化スズ、酸化アンチモン、酸化インジウム、酸化ビスマス、スズをドープした酸化インジウム、アンチモンやタンタルをドープした酸化スズ及びアンチモンをドープした酸化ジルコニウムなどが挙げられる。これらは単独で用いることも、二種以上を組み合わせて用いることもできる。二種以上を組み合わせて用いる場合は、単に混合しても、固溶体や融着させた形にしてもよい。
【００７３】
また、本発明において用いられる導電性粒子の平均粒径は、表面層の透明性の点で０．３μｍ以下であることが好ましく、特には０．１μｍ以下であることが好ましい。
【００７４】
導電性粒子は、層中でできるだけ均一に分散していることが好ましく、導電性粒子と化合物との混合割合は、導電性粒子の粒径や抵抗率の組み合わせにより適宜設定される。
【００７５】
更に、本発明においては、表面層に感光体表面の滑り性などを向上させるために、フッ素原子含有樹脂粒子を分散させることが好ましい。
【００７６】
フッ素原子含有樹脂粒子としては、四フッ化エチレン樹脂、三フッ化塩化エチレン樹脂、六フッ化エチレンプロピレン樹脂、フッ化ビニル樹脂、フッ化ビニリデン樹脂、二フッ化ニ塩化エチレン樹脂及びこれらの共重合体を含むフッ素原子含有樹脂粒子の一種または二種以上を適宜選択するのが好ましいが、特に四フッ化エチレン樹脂やフッ化ビニリデン樹脂が好ましい。これらの樹脂粒子の分子量や粒径は適宜選択することができ、特に制限されるものではない。
【００７７】
本発明においては、連鎖重合性官能基を有する化合物を含有している溶液中で導電性粒子及びフッ素原子含有樹脂を凝集させないように、分散剤を用いることが好ましい。また、導電性粒子の表面をフッ素原子含有化合物で表面処理することが好ましい。表面処理を行うことにより、化合物溶液中での導電性粒子とフッ素原子含有樹脂粒子の分散性を向上させることができ、経時に伴って発生する二次粒子の形成などが生じにくく、分散安定性をより向上させることができる。
【００７８】
また、本発明においては、表面層中に酸化防止剤、紫外線吸収剤及び可塑剤などの添加剤を必要に応じ添加することもできる。
【００７９】
本発明における支持体の単位面積当たりの熱容量は、０．３５Ｊ／ｃｍ^２・Ｋ以上であり、好ましくは０．４５Ｊ／ｃｍ^２・Ｋ以上である。熱容量が０．３５Ｊ／ｃｍ^２・Ｋに満たないと電子線照射時の被照射体の温度を十分に制御することができずに、本発明の顕著な効果を得ることができない。熱容量は、支持体の組成や厚さによって制御することができる。
【００８０】
支持体の材質は、導電性を有していればいずれのものでもよく、例えばアルミニウム、ステンレス、ニッケル及び銅などの金属や合金、更には導電処理された紙やプラスチックなどが挙げられる。これらの中では、生産性、コスト、電気的特性及び安定性などの点で特にアルミニウムが好ましい。その形状は円筒状シリンダーまたはフィルムなど適用される電子写真装置に応じて任意のものとすることができるが、円筒状であることが好ましい。
【００８１】
材質がアルミニウムである場合、支持体の厚さは、１．５〜４．０ｍｍであることが好ましい。１．５ｍｍに満たないと本発明の熱容量の規定を満足しにくく、また、十分な精度を得にくくなる。逆に、４．０ｍｍを超えると支持体自体のコストの抑制といった観点以外にも、支持体の熱容量が大きくなり過ぎて、乾燥時の温度を一定以上に上げるのに時間を要するため、連続して生産しにくくなる。
【００８２】
本発明においては、支持体と感光層の間に、バリアー機能と接着機能を有する中間層を設けることができる。
【００８３】
中間層は感光層の接着性改良、塗工性改良、支持体の保護、基体上の欠陥の被覆、支持体からの電荷注入性改良、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。中間層の材料としては、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、にかわ及びゼラチンなどが挙げられる。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。中間層の膜厚は０．１〜２μｍであることが好ましい。
【００８４】
本発明において用いられる電荷発生物質としては、セレン−テルル、ピリリウム染料、チアピリリウム染料、各種の中心金属及び結晶形、具体的にはα、β、γ、ε及びＸ型などの結晶形を有するフタロシアニン顔料、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、キノシアニン顔料及びアモルファスシリコンなどが挙げられる。
【００８５】
電荷発生層は、上記電荷発生物質を質量比で０．３〜４倍量の結着樹脂及び溶剤と共にホモジナイザー、超音波分散、ボールミル、振動ボールミル、サンドミル、アトライター及びロールミルなどの方法でよく分散し、得られた分散液を塗布し、乾燥することによって形成されるか、または上記電荷発生物質を蒸着することによって形成される。電荷発生層の膜厚は５μｍ以下であることが好ましく、特には０．１〜２μｍであることが好ましい。
【００８６】
本発明において用いられる電荷輸送物質は、電荷輸送物質は電子輸送物質と正孔輸送物質に大別される。
【００８７】
電子輸送物質としては、例えば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、クロラニル及びテトラシアノキノジメタンなどの電子吸引性物質やこれらの電子吸引性物質を高分子化したものなどが挙げられる。
【００８８】
正孔輸送物質としては、ピレン及びアントラセンなどの多環芳香族化合物；カルバゾール系、インドール系、イミダゾール系、オキサゾール系、チアゾール系、オキサジアゾール系、ピラゾール系、ピラゾリン系、チアジアゾール系及びトリアゾール系化合物などの複素環化合物；ｐ−ジエチルアミノベンズアルデヒド−Ｎ，Ｎ−ジフェニルヒドラゾン及びＮ，Ｎ−ジフェニルヒドラジノ−３−メチリデン−９−エチルカルバゾールなどのヒドラゾン系化合物；α−フェニル−４'−Ｎ，Ｎ−ジフェニルアミノスチルベン及び５−［４−（ジ−ｐ−トリルアミノ）ベンジリデン］−５Ｈ−ジベンゾ［ａ，ｂ］シクロヘプテンなどのスチリル系化合物；ベンジジン系化合物；トリアリールメタン系化合物；トリフェニルアミン系化合物；及びこれらの化合物から誘導される基を主鎖または側鎖に有するポリマーなどが挙げられる。
【００８９】
これら有機の電荷輸送物質の他に、セレン、セレン−テルル、アモルファスシリコン及び硫化カドミウムなどの無機物質も用いることができる。また、これらの電荷輸送物質は単独で用いても二種以上組み合わせてもよく、更に、上記以外の電荷輸送物質を使用することも可能である。
【００９０】
電荷輸送層が表面層であり、電荷輸送物質と連鎖重合性官能基を有する化合物を電子線照射によって硬化することによって得られた樹脂を含有する場合、これらの配合割合は、樹脂１００質量部あたり電荷輸送物質を１０〜５００質量部とすることが好ましい。
【００９１】
なお、電気的特性及び機械的特性の観点からは、連鎖重合性官能基を有する化合物自体が電荷輸送機能をも有し、上述のような電荷輸送物質を用いない方が好ましい。
【００９２】
また、連鎖重合性官能基を有する化合物を電子線照射によって硬化することによって得られた樹脂以外にも、本発明の顕著な効果を得ることができる範囲で、ポリカーボネート樹脂、ポリアリレート樹脂、ポリスチレン樹脂及びポリメチルメタクリレート樹脂などの成膜性のある樹脂を含有することもできる。
【００９３】
電荷輸送層が表面層である場合は、膜厚は１〜４０μｍであることが好ましく、特には５〜３０μｍであることが好ましい。
【００９４】
電荷輸送層が表面層ではなく、電荷輸送層上に保護層が形成されている場合は、電荷輸送層は電荷輸送物質及び必要に応じてポリカーボネート樹脂、ポリアリレート樹脂、ポリスチレン樹脂及びポリメチルメタクリレート樹脂などの成膜性のある樹脂を含有する。この際の膜厚は、電荷輸送層が表面層である場合よりも薄いことが好ましく、具体的には１〜２０μｍであることが好ましく、特には５〜１５μｍであることが好ましい。
【００９５】
感光層上に形成される保護層が表面層である場合、かかる保護層は少なくとも連鎖重合性官能基を有する化合物を電子線照射によって硬化することによって得られた樹脂を含有する。
【００９６】
保護層は、電子写真特性上、何らかの電荷輸送機能を有している必要が好ましい。上述のような電荷輸送物質を保護層に含有させる場合は、電荷輸送層内に含有させる電荷輸送物質と保護層内に含有させる電荷輸送物質は、同じ物質である必要はない。但し、電荷輸送層が表面層である場合と同様、電気的特性及び機械的特性の両面から連鎖重合性官能基を有する化合物自体が電荷輸送機能をも有することが好ましい。
【００９７】
また、電荷輸送層が表面層である場合と同様、連鎖重合性官能基を有する化合物を電子線照射によって硬化することによって得られた樹脂以外にも、本発明の顕著な効果を得ることができる範囲で、ポリカーボネート樹脂、ポリアリレート樹脂、ポリスチレン樹脂及びポリメチルメタクリレート樹脂などの成膜性のある樹脂を含有することもできる。
【００９８】
保護層の膜厚は１〜１０μｍであることが好ましく、特には３〜７μｍであることが好ましい。
【００９９】
本発明の電子写真プロセスカートリッジは、複数の工程を実現することのできる手段や装置などが電子写真感光体と一体的に構成され、かつ電子写真装置本体に着脱自在に設けられるものであり、本発明の電子写真感光体を具備する構成であれば、用いる手段や装置及び部材などは任意に選択することができる。
【０１００】
また、本発明の電子写真装置は、本発明の電子写真感光体に、形成すべき画像に応じた潜像を形成し、これを現像し、普通紙やＯＨＰシートなどの、画像を表示するための記録媒体（転写材）に画像を転写するものであれば特に限定されるものではなく、上記電子写真感光体の他に、従来から知られている種々の手段、装置及び部材などを必要に応じて用いることができる。
【０１０１】
次に、本発明のプロセスカートリッジを具備する電子写真装置の概略構成の例を図２に示す。
【０１０２】
図において、１は本発明の電子写真感光体であり、矢印方向に所定の周速度で回転駆動される。電子写真感光体１はその回転過程で帯電手段２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、次いで像露光手段３により光像露光Ｌ（スリット露光・レーザービーム走査露光など）を受ける。これにより電子写真感光体１の周面に露光像に対応した静電潜像が順次形成されていく。図２においては、電子写真感光体１の均一帯電手段２として接触帯電手段であるローラー帯電器が使用されている。
【０１０３】
形成された静電潜像は、現像手段４でトナー現像され、そのトナー現像像が転写手段５により不図示の給紙部から電子写真感光体１と転写手段５との間に電子写真感光体１の回転と同期取りされて給送された転写材Ｐの面に順次転写されていく。像転写を受けた転写材Ｐは感光体面から分離されて像定着手段８へ導入されて像定着を受けて機外へプリントアウトされる。
【０１０４】
像転写後の電子写真感光体１の表面はクリーニング手段（クリーニングブレード）６にて転写残りトナーの除去を受けて清浄面化され、前露光手段７により除電処理がされて繰り返して像形成に使用される。なお、本例のように、一次帯電手段２が接触帯電手段である場合は、前露光手段７は必ずしも必要ではない。
【０１０５】
上述の電子写真感光体、帯電手段、現像手段及びクリーニング手段などの構成要素のうち、複数のものを装置ユニットとして一体に結合して構成し、このユニットを装置本体に対して着脱自在にしたものが本発明のプロセスカートリッジである。例えば、電子写真感光体１とクリーニング手段６とを一体化して一つの装置ユニットとし、装置本体のレールなどの案内部材を用いて着脱自在の構成にしてもよい。このとき上記の装置ユニットに帯電手段及び／または現像手段を伴って構成してもよい。なお、図２には、電子写真感光体１、帯電手段２、現像手段４及びクリーニング手段６を一体的かつ電子写真装置本体に着脱自在に構成されたプロセスカートリッジが示されている。本実施の形態では、支持部材９によって各手段などが所定位置に一体的に支持され、電子写真装置本体に設けられた案内部材１０によって各手段などを支持している支持部材９がプロセスカートリッジとして装置本体に対して着脱自在に設けられている。
【０１０６】
本発明における露光手段、現像手段、転写手段及びクリーニング手段などの通常の電子写真プロセスを行うために必要な手段は何ら限定されるものではなく、独立したクリーニング手段を有さない、所謂クリーナーレス方式の電子写真装置とすることも可能である。
【０１０７】
本発明は、前記本発明に関わる電子写真感光体を備えた電子写真装置として構成され、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、液晶プリンター及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。
【０１０８】
【実施例】
以下に本発明を実施例及び比較例により詳細に説明するが特にこれらに限定されるものではない。
【０１０９】
（実施例１）
Ｎ−メトキシメチル化ナイロン５部（質量部；以下同様）をメタノール９５部中に溶解し、中間層用塗料を調整した。この塗料をホーニング処理した外径φ３０ｍｍのアルミニウムシリンダー（厚さ：１．５０ｍｍ、単位面積当たりの熱容量：０．３６６Ｊ／ｃｍ^２・Ｋ）上に浸漬コーティング法によって塗布し、１００℃で２０分間乾燥することによって、膜厚０．６５μｍの中間層を形成した。
【０１１０】
ＣｕＫαのＸ線回折におけるブラック角２θ±０．２°の７．４°及び２８．２°に強いピークを有するヒドロキシガリウムフタロシアニン結晶３部、ポリビニルブチラ−ル（商品名：エスレックＢＭ２、積水化学（株）製）１．５部及びシクロヘキサノン３５部を、φ１ｍｍのガラスビ−ズを用いたサンドミル装置で２４時間分散し、その後酢酸エチル６０部を加えて電荷発生層用塗料を調製した。この塗料を前記の中間層の上に浸漬コーティング法で塗布し、１０５℃で１０分間乾燥することによって、膜厚０．１８μｍの電荷発生層を形成した。
【０１１１】
次に、電荷輸送物質として下記構造式（Ｄ−１）で示されるスチリル化合物４．５部及びビスフェノールＺ型ポリカーボネート（粘度平均分子量４５，０００）５．５部をモノクロロベンゼン３８ｇに溶解し、電荷輸送層用塗料を調製した。この塗料を前記の電荷発生層の上に浸漬コーティング法で塗布し、１００℃で６０分間乾燥することによって、膜厚１２μｍの電荷輸送層を形成した。
【０１１２】
【外１０】

【０１１３】
次いで、前記化合物例Ｎｏ．９の連鎖重合性官能基を有する正孔輸送性化合物６０部をエタノール５０部及びイソプロピルアルコール２０部の混合溶媒中に溶解し、保護層用塗料を調整した。この塗料を前記の電荷輸送層上に浸漬塗布方法で塗布し、４０℃で１０分乾燥後、図１に示す電子線照射装置を用いて電子線を照射した。
【０１１４】
被照射体は電子線照射窓部の下部までベルトコンベアーで搬送され、照射部で搬送を止め、被照射体を回転しながら電子線を照射し（照射開始時の被照射体の温度は２５℃）、照射終了後、再び搬送され外部に搬出される。このとき、電子線照射部における有効電子線照射幅（被照射体表面での電子線密度分布において、そのピーク位置の１／ｅ以上である幅）は４ｃｍであった。電子線照射条件は、電子線吸収線量率が１×１０^６Ｇｙ／ｓｅｃ（有効電子線照射幅内での電子線吸収線量／被照射体表が有効電子線照射幅内に存在する時間）で、加速電圧が１５０ｋＶで、電子線吸収線量（電子線照射工程中、有効電子線照射幅において被照射体が受ける全吸収線量）が２×１０^５Ｇｙであった。なお、電子線の照射開始から終了までの時間は１．５秒であった。以上の条件にて電子線を照射し、連鎖重合性官能基を有する化合物を硬化することによって、膜厚５μｍの保護層を形成し、電子写真感光体を得た。
【０１１５】
このようにして得られた電子写真感光体の、帯電能、感度及び残留電位の電子写真感光体長手方向でのムラを、ドラム感光体試験装置（商品名：シンシア−５９、ジェンテック社製）を用いて以下の方法で測定した。電子写真感光体の両端部から１５ｍｍ以外の残りの部分を本電子写真感光体の有効部分と考え、有効部分を長手方向に５等分した５ヶ所でそれぞれ電位を測定した。なお、浸漬コーティング時の下端部側からそれぞれの測定箇所を（ａ）、（ｂ）、（ｃ）、（ｄ）及び（ｅ）とした。
【０１１６】
まず、ＬＡＳＥＲ ＳＨＯＴ ＬＢＰ−９３０（キヤノン製）が具備するものと同様の帯電ローラーを用いて電子写真感光体を接触帯電した。この際、電子写真感光体中央部の（ｃ）の場所で、電位プローブ位置での暗部電位Ｖ_０が−６５０Ｖになるようにバイアス電圧を制御した（ドラムの回転スピードは６０ｒｐｍに設定）。光源としてはハロゲンランプを用い、フィルターで単色光（７７５ｎｍ）としたものを照射し、電子写真感光体の表面電位が−２００（Ｖ）に減少するのに必要な露光量（Ｖｌ）を求め、感度とした。
【０１１７】
次に、帯電／露光後に波長７００ｎｍの発光ダイオードにより１５μＪ／ｃｍ^２のエネルギーを与えて除電する前露光工程を入れ、前露光後の電子写真感光体の表面電位を残留電位（Ｖｒ）とした。
【０１１８】
電子写真感光体中央部の（ｃ）以外の残りの４箇所については、中央部（ｃ）で暗部電位Ｖ_０が−６５０Ｖになるように制御したのと同じバイアス電圧で帯電し、中央部（ｃ）で感度を求めたのと同じ露光量を照射後、中央部（ｃ）で残留電位を求めたのと同様な前露光を行い、各々場所における電子写真感光体の表面電位を測定、各々の電位と中央部（ｃ）との差分の絶対値をそれぞれ△Ｖ_０、△Ｖｌ及び△Ｖｓｌとした。
【０１１９】
得られた結果を表２に示す。
【０１２０】
次に、この電子写真感光体をＬＡＳＥＲ ＳＨＯＴ ＬＢＰ−９３０（キヤノン製）を現像ボリュームを可変に調整できるように改造したレーザービームプリンターに搭載し、常温常湿下（２３℃、５５％ＲＨ、Ｎ／Ｎ）で、初期暗部電位（Ｖｄ）が−６５０（Ｖ）になるように帯電条件を設定し、これに波長７８０（ｎｍ）のレーザー光を照射して−６５０（Ｖ）の電位を−１７０（Ｖ）まで下げるのに必要な光量（明部電位Ｖｌ）を測定し感度とした。更に、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。なお、その他の条件は、転写電流を＋５．５μＡ、プロセススピードを１０６ｍｍ／ｓｅｃとした。なお、電位の測定箇所は、先のドラム中央部（ｃ）のみとした。
【０１２１】
また、環境を低温低湿下（１５℃／１０％、Ｌ／Ｌ）及び高温高湿（３２℃／８０％、Ｈ／Ｈ）に変え、それぞれ初期暗部電位（Ｖｄ）が−６５０（Ｖ）になるように帯電条件を設定し、上記常温常湿下で−１７０（Ｖ）まで下げるのに必要な露光量と同じ光量を照射した際の明部電位を測定し、常温常湿下での明部電位である−１７０（Ｖ）からの変動量の絶対値を△Ｖｌとした。
【０１２２】
また、上記と同様にして作成した電子写真感光体を上記と同様のレーザービームプリンターに搭載し、常温低湿下（２３℃、１０％ＲＨ、Ｎ／Ｌ）で連続１０,０００枚の通紙耐久を行って、初期と耐久直後の暗部電位と明部電位の変動量を△Ｖｄと△Ｖｌを測定した。なお、初期の電位設定は上記と同様で、暗部電位を−６５０（Ｖ）に、明部電位を−１７０（Ｖ）にした。
【０１２３】
更に、上記通紙耐久試験によって生じた電子写真感光体の削れ量を、渦電流式膜厚計（カールフィッシャー社製）を用いて測定した。測定は電子写真感光体の長手方向の任意の１０点で行い、それらの平均値を削れ量とした。
【０１２４】
加えて、上記と同様にして作成した電子写真感光体を上記と同様のレーザービームプリンターに搭載し、常温常湿下（２３℃／５５％ＲＨ、Ｎ／Ｎ）で、暗部電位を−６５０Ｖに、明部電位を−１７０Ｖに設定し、以下のようにしてゴーストの程度を評価した。
【０１２５】
まず、初期に、適当な文字画像（５ポイント）を電子写真感光体一周分出力後、１ドット１スペースのドット密度のハーフトーン画像及び全面黒画像を出力し、ゴースト現象が生じているかどうかを確認した。次に、約２ｍｍ幅の線が縦横７ｍｍおきに存在する画像を２０００枚連続で出力した後、１ドット１スペースのドット密度の全面ハーフトーン画像及び全面黒画像を出力し、ゴースト現象が生じているかどうかを確認した。
【０１２６】
出力はレーザービームプリンターの現像ボリュームのＦ５（中心値）とＦ９（濃度薄い）で各々サンプリングした。評価基準は、Ｆ５とＦ９のいずれでもハーフトーン画像、全面黒画像ともにゴーストが生じていないものをランク５とし、Ｆ９でハーフトーン画像を出力した際にはゴーストが生じているが全面黒画像を出力した際にはゴーストが生じていないものをランク４、Ｆ５でハーフトーン画像を出力した際にはゴーストが生じているが全面黒画像を出力した際にはゴーストが生じていないものをランク３、Ｆ９で全面黒画像を出力した際にもゴーストが生じているものをランク２、Ｆ５で全面黒画像を出力した際にもゴーストが生じているものをランク１とした。
【０１２７】
それぞれの結果を以下の表３に示す。
【０１２８】
（実施例２〜１３）
以下の表１に示すように、支持体の厚さや材質を変えることによって支持体の単位面積当たりの熱容量を変化させたり、電子線照射時の被照射体の回転速度や照射時間、電子線照射時のビーム電流値や加速電圧を調整することによって電子線吸収線量率を変化させた以外は実施例１と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１２９】
（実施例１４〜２０）
実施例１の保護層に使用した化合物例Ｎｏ．９の連鎖重合性官能基を有する正孔輸送性化合物を化合物例Ｎｏ．１２の化合物に代え、更に上記実施例２〜１３で行ったように支持体の単位面積当たりの熱容量や、電子線吸収線量率を変化させた以外は実施例１と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３０】
（実施例２１〜２２）
表面を鏡面仕上げした肉厚の異なるアルミニウム素管のそれぞれについて、脱脂剤（キザイ（株）製、商品名ＮＧ−＃３０）３０ｇを水１０００ｇに溶解させた溶液中にて６０℃、５分間脱脂洗浄を行った。次いで、各アルミニウム素管を水洗し、７％硝酸に２５℃で１分間浸漬し、更に水洗を行った。その後、１８０ｇ／ｌの硫酸電解液中（溶存アルミニウムイオン濃度７ｇ／ｌ）で１．２Ａ／ｄｍ^２の電流密度で処理を行い、平均膜厚７μｍの陽極酸化膜を形成した。次いで水洗後、酢酸ニッケルを主成分とする高温封孔剤（奥野製薬工業（株）製、商品名トップシールＤＸ−５００）１０ｇを水１ｌに溶解させた水溶液に９５℃で３０分間浸し、封孔処理した。更に超音波洗浄処理し、乾燥した。
【０１３１】
このようにして得た支持体を用いた以外は実施例１４と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３２】
（実施例２３）
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、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部及びシリコーン化合物（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のガラスビーズを用いたサンドミル装置で２時間分散して調整した。
【０１３３】
支持体として外径φ３０ｍｍのアルミニウム素管（単位面積当たりの熱容量：０．４８６Ｊ／ｃｍ^２・Ｋ）を用い、得られた導電層用塗料を支持体上に浸漬塗布方法で塗布し、１５０℃で３０分乾燥して、膜厚１２μｍの導電層を形成し、形成した導電層上に中間層を設ける以外は実施例１４と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３４】
（実施例２４）
電子線照射開始時の被照射体の温度を４０℃にした以外は実施例３と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３５】
（実施例２５）
電子線照射開始時の被照射体の温度を７０℃にした以外は実施例３と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３６】
（実施例２６）
実施例３の保護層で使用した化合物例Ｎｏ．９の連鎖重合性官能基を有する正孔輸送性化合物６０部を化合物例Ｎｏ．１５の化合物４５部及び化合物例Ｎｏ．３４の化合物１５部に代えた以外は実施例３と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３７】
（実施例２７〜２８）
実施例２〜１３と同様な方法で、表１に示したように電子線吸収線量率を変化させた以外は実施例３と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３８】
（実施例２９〜３０）
実施例２〜１３と同様な方法で、表１に示したように電子線吸収線量率及び加速電圧を変化させた以外は実施例１４と同様にして電子写真感光体を作成し、評価した。結果を表２及び表３に示す。
【０１３９】
【表１】

【０１４０】
【表２】

【０１４１】
【表３】

【０１４２】
【表４】

【０１４３】
【表５】

【０１４４】
【表６】

【０１４５】
（比較例１〜７）
以下の表６に示すように、支持体の膜厚や材質を変えることによって支持体の単位面積当たりの熱容量を変化させたり、電子線照射時の被照射体の回転速度や照射時間、電子線照射時のビーム電流値や加速電圧を調整することによって電子線吸収線量率を変化させた以外は実施例１と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
【０１４６】
（比較例８〜９）
以下の表４に示すように、支持体の単位面積当たりの熱容量及び電子線吸収線量率を変化させた以外は実施例１４と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
【０１４７】
（比較例１０）
電子線吸収線量率を１×１０^８Ｇｙ／ｓｅｃに変えた以外は実施例２１と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
【０１４８】
（比較例１１）
支持体の単位面積当たりの熱容量を０．３３５Ｊ／ｃｍ^２・Ｋに変えた以外は実施例２３と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
【０１４９】
（比較例１２）
電子線吸収線量率を１×１０^８Ｇｙ／ｓｅｃに変えた以外は実施例２３と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
（比較例１３）
電子線吸収線量率を７×１０^２Ｇｙ／ｓｅｃに変えた以外は実施例２９と同様にして電子写真感光体を作成し、評価した。結果を表５及び表６に示す。
【０１５０】
【表７】

【０１５１】
【表８】

【０１５２】
【表９】

【０１５３】
（実施例３１）
アルコール可溶性共重合ナイロン（商品名：アミランＣＭ−８０００、東レ（株）製）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。この塗料を切削加工した外径φ３０ｍｍのアルミニウムシリンダー（厚さ：１．５０ｍｍ、単位面積当たりの熱容量：０．３６６Ｊ／ｃｍ^２・Ｋ）上に浸漬コーティング法によって塗布し、１２０℃で６０分間乾燥することによって、膜厚０．８μｍの中間層を形成した。
【０１５４】
ＣｕＫαのＸ線回折におけるブラック角２θ±０．２°の９．０°、１４．２°、２３．９°及び２８．２°に強いピークを有するオキシチタニウムフタロシアニン結晶１．２部、ポリビニルブチラ−ル（商品名：エスレックＢＸ−１、積水化学（株）製）１．０部及びシクロヘキサノン３５部、φ１ｍｍのガラスビ−ズを用いたサンドミル装置で３時間分散して、その後テトラヒドロフラン６０部を加えて電荷発生層用塗料を調製した。この塗料を前記の中間層の上に浸漬塗布方法で塗布し、１０５℃で１０分間乾燥することによって、膜厚０．１５μｍの電荷発生層を形成した。
【０１５５】
次に、電荷輸送物質として化合物例Ｎｏ．１８の化合物６０部をクロロベンゼン４０部及びジクロロメタン１０部に溶解し、電荷輸送層用塗料を作製した。この液を前記電荷発生層上に浸漬塗布し、５０℃で１５分間乾燥後、前記実施例１と同様な電子線照射装置を用いて電子線を照射した。照射条件は表７に示す。
【０１５６】
また、得られた電子写真感光体を実施例１と同様にして評価した。結果を表８及び表９に示す。
【０１５７】
（実施例３２〜３９）
以下の表７に示すように、支持体の膜厚を変えることによって支持体の単位面積当たりの熱容量を変化させたり、電子線照射時の被照射体の回転速度や照射時間、電子線照射時のビーム電流値や加速電圧を調整することによって電子線吸収線量率を変化させた以外は実施例３１と同様にして電子写真感光体を作成し、評価した。結果を表８及び表９に示す。
【０１５８】
（実施例４０）
実施例３１の電荷発生層を以下のようにして形成した以外は実施例３１と同様にして電子写真感光体を作成し、評価した。結果を表８及び表９に示す。
【０１５９】
下記構造式（Ｐ−１）で示されるアゾ顔料３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３００００）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１５時間分散し、これに８０部のテトラヒドロフランを加え希釈した。得られた溶液を中間層上に浸漬コーティング法により塗布し、乾燥することによって、膜厚が０．１５μｍの電荷発生層を形成した。
【０１６０】
【外１１】

【０１６１】
（実施例４１）
支持体の単位面積当たりの熱容量を０．６０８Ｊ／ｃｍ^２・Ｋに変えた以外は実施例４０と同様にして電子写真感光体を作成し、評価した。結果を表８及び表９に示す。
【０１６２】
（実施例４２）
実施例３５の吸収線量率を以下の表７に示すように変えた以外は実施例３５と同様にして電子写真感光体を作成し、評価した。結果を表８及び表９に示す。
【０１６３】
【表１０】

【０１６４】
【表１１】

【０１６５】
【表１２】

【０１６６】
（比較例１４〜１８）
以下の表１０に示すように、支持体の膜厚を変えることによって支持体の単位面積当たりの熱容量を変化させたり、電子線照射時の被照射体の回転速度、電子線照射時のビーム電流値や加速電圧を調整することによって電子線吸収線量率を変化させた以外は実施例３１と同様にして電子写真感光体を作成し、評価した。結果を表１１及び１２に示す。
【０１６７】
（比較例１９）
支持体の単位面積当たりの熱容量を０．２９２Ｊ／ｃｍ^２・Ｋに変えた以外は実施例３９と同様にして電子写真感光体を作成し、評価した。結果を表１１及び１２に示す。
【０１６８】
（比較例２０）
支持体の単位面積当たりの熱容量を０．２９２Ｊ／ｃｍ^２・Ｋに変えた以外は実施例４０と同様にして電子写真感光体を作成し、評価した。結果を表１１及び１２に示す。
【０１６９】
（比較例２１）
電子線吸収線量率を５×１０^７Ｇｙ／ｓｅｃに変えた以外は比較例２０と同様にして電子写真感光体を作成し、評価した。結果を表１１及び１２に示す。
【０１７０】
（比較例２２）
電子線吸収線量率を５×１０^２Ｇｙ／ｓｅｃに変えた以外は実施例４２と同様にして電子写真感光体を作成し、評価した。結果を表１１及び１２に示す。
【０１７１】
【表１３】

【０１７２】
【表１４】

【０１７３】
【表１５】

【０１７４】
【発明の効果】
以上のように、本発明によれば、優れた機械的耐久性を有するだけではなく、優れた感度を有し、残留電位の上昇、感度ムラ、帯電ムラ、各種メモリー及び繰り返し使用時における電位変動などの電子写真特性の変化が生じにくい、極めて優れた特性を有する電子写真感光体、かかる電子写真感光体を具備するプロセスカートリッジ及び電子写真装置を提供することが可能となった。
【図面の簡単な説明】
【図１】本発明の電子写真感光体を作成する際に用いられる電子線照射装置の概略構成の例を示す図である。
【図２】本発明のプロセスカートリッジを具備する電子写真装置の概略構成の例を示す図である。
【符号の説明】
１ 本発明の電子写真感光体
１’ 被照射体
２ 帯電手段
３ 像露光手段
４ 現像手段
５ 転写手段
６ クリーニングブレード
７ 前露光手段
８ 像定着手段
９ 転写材搬送装置
１０ 支持部材
１０’ 案内部材
１１ 電子線発生部
１２ ターミナル
１２ａ フィラメント
１２ｂ ハウス
１２ｃ グリッド
１４ 加速管
２０ 照射室
２２ 照射空間
３０ 照射窓部
３２ 窓箔
３４ 窓枠構造体
１００ 支持部材
１１０ 案内部材
Ｌ 光像露光
Ｐ 転写材[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.
[0002]
[Prior art]
2. Description of the Related Art In recent years, organic compounds have been widely used as materials for electrophotographic photoreceptors due to advantages such as a wide latitude in molecular design and high productivity.
[0003]
On the other hand, as a matter of course, the electrophotographic photosensitive member is required to have sensitivity, electrical characteristics, mechanical characteristics, and even optical characteristics according to the electrophotographic process to be applied. In particular, since various electrical and mechanical external forces such as charging, exposure, development, transfer, and cleaning are directly applied to the surface of the electrophotographic photoreceptor that is repeatedly used, durability against the external force is required.
[0004]
Specifically, durability against the occurrence of surface wear and scratches due to rubbing, surface degradation due to electrification (for example, a decrease in transfer efficiency and slipperiness), and degradation against electrical characteristics such as sensitivity reduction and potential reduction are also observed. Required.
[0005]
Since the surface of a photoreceptor using an organic compound is generally a thin resin layer, the characteristics of the resin are very important, and acrylic resins and polycarbonate resins have been put to practical use as resins satisfying the above-mentioned various conditions to some extent. . However, in order to further increase the durability of the electrophotographic photoreceptor, it is difficult to say that the film hardness obtained even with these resins is sufficiently high, and that the surface layer is worn when repeatedly used, and further damage is caused. There was a problem that occurred.
[0006]
In addition, if a relatively large amount of a low molecular weight compound such as a charge transport material is added to the photosensitive layer for the purpose of further increasing the sensitivity of the electrophotographic photoreceptor, the mechanical strength is remarkably reduced, resulting in repeated use. In addition, problems such as abrasion and scratching of the surface layer are easily generated, and low molecular weight components are precipitated when the electrophotographic photoreceptor is stored for a long period of time to cause layer separation.
[0007]
On the other hand, by using a curable resin as the resin for the charge transport layer, the mechanical strength of the layer is increased, and the abrasion resistance and scratch resistance during repeated use are improved. No., for example. However, even if a curable resin is used, the low-molecular-weight components such as the charge transport substance still function as a plasticizer in the binder resin, and the problems of precipitation and layer separation as described above are fundamental. Has not been resolved. In a charge transport layer composed of a charge transport material and a binder resin, the charge transport ability depends on the resin used. For example, when a curable resin having sufficiently high hardness is used, sufficient charge transport is performed. However, it has not been possible to satisfy both mechanical durability and charge transporting ability at a high level.
[0008]
Further, JP-A-5-216249 and JP-A-7-72640 disclose that a monomer having a carbon-carbon double bond reacts with a carbon-carbon double bond of a charge transporting substance by heat or light energy. The formation of a charge transport layer by curing is disclosed. However, the portion having the charge transporting ability is merely fixed in a pendant manner to the main skeleton of the polymer, and the plastic action such as the charge transporting material as described above cannot be sufficiently eliminated. Target strength is not enough. Further, when the concentration of the portion having the charge transporting ability is increased to improve the charge transporting ability, the crosslink density becomes low, and sufficient mechanical strength cannot be secured. Furthermore, there is a concern that the initiators required for polymerization may affect the electrophotographic properties.
[0009]
As another solution, JP-A-8-248649 and the like disclose forming a charge transport layer using a thermoplastic resin having a group having a charge transport ability introduced into a main chain. . However, as compared with the conventional molecular dispersion type charge transport layer, it is effective for precipitation and layer separation, and although the mechanical strength is improved, since it is a thermoplastic resin to the last, its mechanical strength is There was a limit, and handling and productivity including the solubility of the resin were not sufficient.
[0010]
Therefore, the present inventors have disclosed that the above technical problems can be greatly improved by crosslinking / curing a compound having a chain polymerizable functional group by irradiation with radiation, as disclosed in JP-A-11-265085 and JP-A-2000-2000. 066425, JP-A-2000-206715, JP-A-2000-206716, JP-A-2000-258932 and JP-A-2001-166514.
[0011]
[Patent Document 1]
JP-A-2-127652
[Patent Document 2]
JP-A-5-216249
[Patent Document 3]
JP-A-7-72640
[Patent Document 4]
JP-A-11-265085
[Patent Document 5]
JP 2000-066425 A
[Patent Document 6]
JP 2000-206715 A
[Patent Document 7]
JP 2000-206716 A
[Patent Document 8]
JP 2000-258932 A
[Patent Document 9]
JP 2001-166514 A
[0012]
[Problems to be solved by the invention]
However, since radiation having a high energy is applied to the electrophotographic photoreceptor, the characteristics of the electrophotographic photoreceptor may greatly change depending on conditions such as irradiation. For example, in order to increase the crosslink density by promoting the polymerization / crosslinking reaction of the chain-polymerizable functional group as much as possible to improve mechanical properties such as abrasion resistance, high-intensity radiation is required to some extent. When the strength is increased, deterioration of each material in the photosensitive layer is promoted, and various electrical characteristics such as sensitivity, residual potential, potential fluctuation during durability, and ghost of the electrophotographic photosensitive member may be deteriorated. In addition, sensitivity unevenness, charging unevenness, shaving unevenness, and the like may occur.
[0013]
The object of the present invention is not only to have excellent mechanical durability, but also to have excellent sensitivity, electrophotographic properties such as increase in residual potential, uneven sensitivity, uneven charging, various memories and potential fluctuations when used repeatedly. It is an object of the present invention to provide an electrophotographic photoreceptor which hardly causes a change and can exhibit stable performance not only in the initial stage but also in repeated use.
[0014]
It is another object of the present invention to provide a process cartridge and an electrophotographic apparatus having such an electrophotographic photosensitive member.
[0015]
[Means for Solving the Problems]
That is, the present invention is an electrophotographic photoreceptor having a photosensitive layer on a support, having a surface layer containing a resin obtained by curing a compound having a chain polymerizable functional group by electron beam irradiation. In the electrophotographic photosensitive member, the heat capacity per unit area of the support is 0.35 J / cm. ² An electron beam absorption dose rate of 1 × 10 on the surface of the irradiation object in the irradiation of the electron beam which is not less than K ³ ~ 2 × 10 ⁷ Gy / sec.
[0016]
Further, the present invention is a process cartridge and an electrophotographic apparatus provided with such an electrophotographic photosensitive member.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
As described above, in the present invention, when forming a surface layer of an electrophotographic photoreceptor, a compound having a chain polymerizable functional group is irradiated with an electron beam to polymerize and / or crosslink and cure the compound. However, the present inventors have found that the irradiation conditions of the electron beam and the heat capacity of the irradiated object are very important in achieving a high level of both the electrical characteristics and durability of the obtained electrophotographic photosensitive member. Was found. Among these, the most important conditions were the electron beam absorbed dose rate (electron beam absorption amount per unit time) on the surface of the irradiation object at the time of electron beam irradiation and the heat capacity per unit area of the support. In the present invention, by paying attention to these factors and defining them in a specific range, it is extremely excellent that satisfies all of the electrical characteristics such as sensitivity, residual potential and sensitivity unevenness and durability performance such as surface hardness and abrasion property. It has become possible to manufacture electrophotographic photoreceptors.
[0018]
The object to be irradiated in the present invention is a support on which a layer to be irradiated with an electron beam is formed. Specifically, an intermediate layer or a photosensitive layer may be provided on a support having a specific heat capacity as necessary. Is formed, and a layer containing a compound having a chain polymerizable functional group is provided thereon as a surface layer.
[0019]
The polymerization or cross-linking reaction of the chain polymerizable functional group by electron beam irradiation can be influenced by the electron beam absorption dose rate on the surface of the object to be irradiated during electron beam irradiation and the temperature of the object to be irradiated during electron beam irradiation. For example, the higher the electron beam absorbed dose rate is, the higher the temperature is, and the higher the temperature is, the more these reactions are promoted. However, in parallel with this, side reactions such as decomposition are also promoted. In particular, since the electron beam used in the present invention has a relatively large energy, not only the material used for the surface layer containing the compound having a chain polymerizable functional group is deteriorated, but also the charge transport layer below the surface layer, Even various materials used for the layers such as the generation layer and the intermediate layer are easily deteriorated. When the deterioration occurs, characteristics such as chargeability, sensitivity, residual potential, potential fluctuation during durability, and memory characteristics such as ghost deteriorate.
[0020]
Conversely, if the electron beam absorption dose rate is reduced or the temperature is lowered, side reactions such as deterioration can be suppressed, but the polymerization or cross-linking reaction of the compound having a chain polymerizable functional group tends not to proceed sufficiently. By forming a high hardness surface layer, which is one of the major objects of the present invention, it becomes difficult to provide an electrophotographic photosensitive member having extremely excellent printing durability and scratch resistance.
[0021]
As for the temperature, the higher the temperature, the more easily the material contained in the layer below the surface layer migrates to the surface layer before electron beam irradiation. The migrated material inhibits the polymerization or cross-linking reaction of the compound having a chain polymerizable functional group, thereby deteriorating the electrical characteristics and durability of the obtained electrophotographic photosensitive member. Even small amounts of this migration can have a significant effect on properties.
[0022]
When forming a surface layer containing a compound having a chain polymerizable functional group on a photosensitive layer that is currently commonly used, select a solvent that does not mix as much as possible with the lower layer as a solvent used for the surface layer. Even so, it is preferable that the temperature at the time of electron beam irradiation is not as high as possible, and it is preferable that the temperature is room temperature, and at most 60 ° C. or less in consideration of productivity. If the lower layer is cured before forming the surface layer so that the lower layer material does not migrate to the surface layer, the temperature may be higher than the previous temperature and the curing reaction may be performed. However, as described below, it is not preferable from the viewpoint of temperature unevenness.
[0023]
The energy of the electron beam irradiation contributes to the generation of active species such as radical species that cause the polymerization or cross-linking reaction of the chain polymerizable functional group, while being converted to heat and increasing the temperature of the irradiation target. At that time, temperature unevenness easily occurs regardless of the temperature of the irradiation target at the start of the electron beam irradiation, and the curability of the surface layer and the above-described deterioration of the various materials partially occur differently. As a result, the electrical characteristics of the electrophotographic photosensitive member such as charging unevenness and sensitivity unevenness are deteriorated, and the durability of the electrophotographic photosensitive member is deteriorated such that the surface layer is easily scraped or scratched. The higher the temperature at the time of electron beam irradiation, the more difficult it is to control the uniformity of the temperature. Therefore, it is preferable that the temperature at the time of electron beam irradiation is not as high as possible, and irradiation at 60 ° C. or less, particularly at room temperature, is preferable. preferable.
[0024]
The present inventors control the electron beam absorption dose rate and the heat capacity per unit area of the support at the surface of the irradiation object at the time of electron beam irradiation, thereby preventing the temperature unevenness occurring at the time of electron beam irradiation. This led to the invention of the present application.
[0025]
Next, 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 high molecular substance is largely divided into chain polymerization and sequential polymerization. (New Edition) ”(published on July 25, 1995 (1st edition, 8th edition) by Gihodo Publishing Co., Ltd.), p. 24, the reaction proceeds mainly through intermediates such as radicals or ions. It refers to unsaturated polymerization, ring-opening polymerization, isomerization polymerization and the like. The chain polymerizable functional group means a functional group capable of performing the above-described reaction mode, and in the present invention, unsaturated polymerization is particularly preferable.
[0026]
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. Most. Particularly preferred unsaturated polymerizable functional groups for use in the present invention are represented by the following formula (1).
[0027]
[Outside 1]

[0028]
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 that may have a substituent; Aryl groups such as benzyl group, phenethyl group, naphthylmethyl group, furfuryl group and thienyl group, and optionally substituted aryl groups such as phenyl group, naphthyl group, anthryl group, pyrenyl group, thiophenyl group and furyl group , A methoxy group, an ethoxy group, a propoxy group and other alkoxy groups, a CN group, a nitro group, -COOR ¹ Or CONR ² R ³ Is shown.
[0029]
W is 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-,- CH ₂ -, -O-, -OO-, -S- or -CONR ⁴ Indicated by-.
[0030]
R ¹ , R ² , R ³ And R ⁴ Is 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 An aryl group such as a phenyl group, a naphthyl group and an anthryl group which may have a substituent, ² And R ³ May be the same or different. F indicates 0 or 1.
[0031]
E, W and R ^1-4 Examples of the substituent which may have a halogen atom such as fluorine, chlorine, bromine and iodine, a nitro group, a cyano group, a hydroxyl group, an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a methoxy group, Alkoxy groups such as ethoxy group and propoxy group, aryloxy groups such as phenoxy group and naphthoxy group, benzyl group, phenethyl group, aralkyl group such as naphthylmethyl group, furfuryl group and thienyl group or phenyl group, naphthyl group, anthryl group and And an aryl group such as a pyrenyl group.
[0032]
Preferred examples of the unsaturated polymerizable functional group represented by the above formula (1) are shown below, but are not limited thereto.
[0033]
[Outside 2]

[0034]
In the above formula, 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, a naphthylmethyl group, and a furfuryl group. And an aralkyl group such as 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.
[0035]
Examples of the substituent which R may have include a halogen atom such as fluorine, chlorine, bromine and iodine, a nitro group, a cyano group, a hydroxyl group, an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, and a methoxy group. , An alkoxy group such as an ethoxy group and a propoxy group, an aryloxy group such as a phenoxy group and a naphthoxy group, an aralkyl group such as a benzyl group, a phenethyl group, a naphthylmethyl group, a furfuryl group and a thienyl group, or a phenyl group, a naphthyl group and an anthryl group. And an aryl group such as a pyrenyl group.
[0036]
Among these, groups represented by the following formulas (2) to (6) are preferable, and acryloyloxy groups of the formula (2) and methacryloyloxy groups of the formula (3) are particularly preferable in terms of polymerization rate and the like.
[0037]
[Outside 3]

[0038]
The compound having an unsaturated polymerizable functional group represented by the formula (1) in the present invention is roughly classified into a monomer and an oligomer by repeating its structural unit. The monomer is a monomer having a relatively small molecular weight without repeating the structural unit having an unsaturated polymerizable functional group represented by the formula (1), and the oligomer is an unsaturated polymerizable compound represented by the formula (1). It is a polymer in which the number of repeating structural units having a functional group is about 2 to 20. Further, a macromer having an unsaturated polymerizable functional group represented by the formula (1) only at the terminal of the polymer or oligomer can be used as the compound for the surface layer of the electrophotographic photoreceptor of the present invention.
[0039]
In the present invention, it is preferable to use a monomer from the viewpoint of satisfying both the electrical characteristics and durability of the electrophotographic photosensitive member. Even when an oligomer or macromer having an unsaturated polymerizable functional group represented by the formula (1) is used, it is preferable to use a mixture with a monomer. Further, monomers having an unsaturated polymerizable functional group represented by the above formula (1) can be further classified according to the number of functional groups in one molecule, and those having one functional group in one molecule are called monofunctional monomers. In the case of two or more, it is called a polyfunctional monomer. In the present invention, it is preferable to use a polyfunctional monomer in order to sufficiently secure the hardness of the photoconductor surface layer.
[0040]
When a compound having a chain polymerizable functional group is used in the form of a solution, as the solvent, in addition to aromatic solvents such as toluene, xylene and monochlorobenzene, dioxane, tetrahydrofuran, ethers such as tetrahydropyran and methylcellosolve, Ketones such as methyl ethyl ketone and methyl butyl ketone, and alcohols such as methanol, ethanol, butanol and propanol can be used.
[0041]
The compound having an unsaturated polymerizable functional group in the present invention is described, for example, in "Ultraviolet Curing System" by Kiyomi Kato (published on February 28, 1989 by Sogo Gijutsu Center), pages 177 to 192. Oligomers having an acryl or methacryl group, and monomers having an acryl or methacryl group described on pages 259 to 302. Further, as the compound having an unsaturated polymerizable functional group in the present invention, a compound having a charge transporting function is preferable from the viewpoint of achieving both durability and electrical characteristics of the electrophotographic photosensitive member. Among them, a hole transporting compound is preferable.
[0042]
Examples of the hole transportable compound having an unsaturated polymerizable functional group include a known hole transportable compound having an unsaturated polymerizable functional group, and an unsaturated polymerizable functional group Any compound may be used as long as it is a compound to which is added. The charge transport material is preferably a hydrazone compound, a pyrazoline compound or a triphenylamine compound as described in the detailed description of the charge transport layer, but is not particularly limited thereto. Any compound having a function can be used.
[0043]
However, in the present invention, in order to sufficiently secure the hardness of the surface layer, even in a compound having an unsaturated polymerizable functional group and having a charge transport function, a plurality of unsaturated polymerizable functional groups may be present in one molecule. It preferably has a group. Specific examples of such compounds are disclosed in, for example, JP-A-2001-175016.
[0044]
Preferred examples of the compound having an unsaturated polymerizable functional group are shown in the following table, but the present invention is not limited to these compounds.
[0045]
[Outside 4]

[0046]
[Outside 5]

[0047]
[Outside 6]

[0048]
[Outside 7]

[0049]
[Outside 8]

[0050]
[Outside 9]

[0051]
Among these, Compound Example No. Compounds (9), (11), (12), (13), (17) and (19) are preferred, and in particular, Compound Examples No. The compounds of (9), (11), (12) and (17) are preferred, and further, Compound Example Nos. Compounds (11) and (12) are preferred, and Compound Examples No. The compound (12) is most preferred.
[0052]
In the present invention, when a surface layer of an electrophotographic photosensitive member having a photosensitive layer on a support is formed by curing a compound having a chain polymerizable functional group by electron beam irradiation, the heat capacity per unit area is reduced. 0.35J / cm ² Using a support of K or more, and making the electron beam absorbed dose rate on the surface of the irradiation object 1 × 10 ³ ~ 2 × 10 ⁷ Gy / sec.
[0053]
The surface layer before being irradiated with the electron beam may be a solution in which the compound having the chain polymerizable functional group is dissolved, a support, an intermediate layer formed on the support as necessary, or an intermediate layer or a support. After coating on a photosensitive layer such as a charge generating layer containing a charge generating substance formed thereon, a charge transporting layer containing a charge transporting substance, or a layer containing both a charge generating substance and a charge transporting substance, drying is performed. It is formed by doing. Alternatively, a solution in which a cured product obtained by reacting a compound having a chain-polymerizable functional group to some extent in advance in a solvent may be dried after coating is applied.
[0054]
Examples of the method for applying the solution include a dip coating method, a spray coating method, a curtain coating method, and a spin coating method.
[0055]
In the present invention, the irradiation target having the surface layer formed as described above is irradiated with an electron beam so as to satisfy a specific condition.
[0056]
As an accelerator for irradiating an electron beam, any type such as a scanning type, an electro-curtain type, a broad beam type, a pulse type, and a laminar type can be used.
[0057]
FIG. 1 shows an example of a schematic configuration of a preferable electron beam irradiation apparatus that can be used for producing the electrophotographic photosensitive member of the present invention.
[0058]
As shown in FIG. 1, the electron beam irradiation apparatus used in the present invention includes an electron beam generator 11 for generating an electron beam, an irradiation chamber 20 for irradiating an electrophotographic photosensitive member with an electron beam, an electron beam generator 11, An irradiation window 30 for introducing the generated electron beam into the irradiation chamber 20 is provided.
[0059]
The electron beam generator 11 has a terminal 12 for generating an electron beam and an acceleration tube 14 for accelerating the electron beam generated in the terminal 12 in a vacuum space. In order to prevent electrons from colliding with gas molecules and losing energy, the inside of the electron beam generator 11 is controlled by an oil diffusion pump (not shown) or the like. ^-4 -10 ^-6 The vacuum of Pa is maintained.
[0060]
The terminal 12 has a linear filament 12a for emitting thermoelectrons, a gun structure 12b having the filament 12a, and a grid 12c for controlling thermoelectrons generated by the filament 12a. If the length of the filament 12a and the grid 12c in the depth direction in the drawing is longer than at least the length of the portion of the irradiation target 1 'to be irradiated with the electron beam, the longitudinal direction of the irradiation target 1' The whole can be irradiated by one electron beam irradiation.
[0061]
The electron beam generator 11 includes a heating power supply (not shown) for heating the filament 12a to emit thermoelectrons, and a control power supply (not shown) for applying a voltage between the filament 12a and the grid 12c. A DC power supply and an acceleration DC power supply for applying a voltage between the grid 12c and the window foil 32 provided on the irradiation window 30 are provided.
[0062]
The irradiation chamber 20 includes an irradiation space 22 for irradiating the surface of the irradiation target 1 ′ with an electron beam. When the surface layer of the electrophotographic photosensitive member is cured as in the examples described below, the interior of the irradiation chamber is set to a deoxidizing atmosphere in order to stabilize the curing. Further, the irradiation target 1 ′ is transported in the direction of the arrow A by a transporting means such as a conveyor in the irradiation chamber 20, and is irradiated with an electron beam by the irradiation unit. In the present invention, it is preferable to rotate the irradiation target 1 ′ when the electron beam is irradiated. After the irradiation is completed, the irradiation target 1 'is transported again in the direction of the arrow A and is taken out.
[0063]
The periphery of the electron beam generator 11 and the irradiation chamber 20 is shielded by lead so that X-rays that are generated secondarily during electron beam irradiation do not leak outside.
[0064]
The irradiation window portion 30 has a window foil 32 made of a metal foil, and a window frame structure 34 that cools the window foil 32 and supports the window foil 32. The window foil 32 separates the vacuum atmosphere in the electron beam generator 10 from the atmosphere in the irradiation chamber 20, and takes out the electron beam into the irradiation chamber 20 through the window foil 32.
[0065]
When a current is applied to the filament 12a by the heating power supply to heat the filament 12a, the filament 12a emits thermoelectrons. The thermoelectrons are distributed in all directions by the control voltage of the control DC power supply applied between the filament 12a and the grid 12c. Gravitate. Of these, only those that have passed through the grid 12c are effectively extracted as electron beams. The electron beam extracted from the grid 12c is accelerated in an acceleration space in the accelerating tube 14 by an accelerating voltage of a DC power supply for acceleration applied between the grid 12c and the window foil 32. Irradiation is performed on the irradiation target 1 ′ that is conveyed through the irradiation chamber 20 through the window foil 32. Normally, the heating power supply and the acceleration DC power supply are set to predetermined values, and the control DC power supply is made variable, whereby the current of the electron beam can be adjusted.
[0066]
The electron beam absorbed dose rate on the surface of the irradiation object in the irradiation of the electron beam defined by the present invention is 1 × 10 ³ ~ 2 × 10 ⁷ Gy / sec, preferably 1 × 10 ⁴ ~ 2 × 10 ⁶ Gy / sec. This electron beam absorbed dose rate is obtained by calculating the electron beam absorbed dose within the effective electron beam irradiation width such that the peak position is 1 / e or more in the electron beam density distribution on the object surface. It is divided by the time within the effective electron beam irradiation width. The absorbed dose can be measured by a general-purpose film dosimeter, for example, FWT-60 (manufactured by FarWest Technology) (however, the absorbed dose that can be directly measured is 1 × 10 ⁵ Gy or less, and 1 × 10 when exceeding Gy ⁵ Estimate from the current value (or time) when measuring the absorbed dose of Gy or less). The electron beam absorbed dose rate can be controlled by the absorbed dose of the electron beam, the acceleration voltage, the irradiation time, the moving speed of the surface of the irradiation object, and the like.
[0067]
In the present invention, the absorbed dose of the electron beam is 1 × 10 ³ ~ 5 × 10 ⁵ Gy, more preferably 5 × 10 ³ ~ 3 × 10 ⁵ Gy is preferred. Absorbed dose is 1 × 10 ³ If it is less than Gy, it becomes difficult to sufficiently cure the surface layer, and 5 × 10 ⁵ If it exceeds Gy, the characteristics of sensitivity and residual potential tend to deteriorate.
[0068]
As for the absorbed dose rate and absorbed dose of the electron beam, the value on the surface of the irradiation target may be measured using the known measuring means as described above, but in the present invention, the absorption dose on the surface of the irradiation target is not necessarily calculated. It is not necessary to measure, and the absorbed dose on the surface of the irradiation target can be calculated from the irradiation dose on the irradiation target. That is, the absorbed dose rate and absorbed dose of the electron beam on the surface of the irradiation target can be controlled by adjusting the output of the electron beam irradiation device.
[0069]
Further, in the present invention, it is preferable that the irradiation time of the electron beam is short (the electron beam absorption dose is large) even if the electron beam absorption dose rate is the same. This is because active species that contribute to polymerization or cross-linking reaction such as radicals generated by an electron beam are deactivated over time, and the reaction rate is reduced. This phenomenon can be improved to some extent by, for example, changing the atmosphere during electron beam irradiation to an inert gas. However, in the present invention, the electron beam irradiation time is preferably 5 seconds or less, and particularly 2 seconds or less. It is preferable that
[0070]
In the present invention, the acceleration voltage of the electron beam is 5 × 10 ⁴ ~ 2 × 10 ⁵ V is preferred. 5 × 10 ⁴ If it is less than V, the curing of the surface layer tends to be uneven in the film thickness direction, and 2 × 10 ⁵ If it exceeds V, deterioration of the electrophotographic photoreceptor tends to occur. The accelerating voltage in the present invention is a DC voltage applied between the terminal 12 and the window foil 32 as an anode in FIG.
[0071]
In the present invention, the surface layer may contain conductive particles, and the conductive particles used include metals, metal oxides, carbon black, and the like, but use a metal oxide in terms of transparency. Is particularly preferred.
[0072]
Examples of the metal include aluminum, zinc, copper, nickel, silver, stainless steel, and those obtained by vapor-depositing these metals on the surfaces of plastic particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony and tantalum-doped tin oxide, and antimony-doped zirconium oxide. . These can be used alone or in combination of two or more. When two or more kinds are used in combination, they may be simply mixed, a solid solution or a fused form.
[0073]
Further, the average particle size of the conductive particles used in the present invention is preferably 0.3 μm or less, particularly preferably 0.1 μm or less from the viewpoint of the transparency of the surface layer.
[0074]
The conductive particles are preferably dispersed as uniformly as possible in the layer, and the mixing ratio of the conductive particles and the compound is appropriately set according to the combination of the particle size and resistivity of the conductive particles.
[0075]
Further, in the present invention, it is preferable to disperse fluorine atom-containing resin particles in the surface layer in order to improve the slipperiness and the like of the photoreceptor surface.
[0076]
Examples of the fluorine atom-containing resin particles include ethylene tetrafluoride resin, ethylene trifluoride chloride resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin, ethylene difluoride ethylene chloride resin, and copolymers thereof. It is preferable to appropriately select one kind or two or more kinds of the fluorine atom-containing resin particles containing the union, and particularly preferable are a tetrafluoroethylene resin and a vinylidene fluoride resin. The molecular weight and particle size of these resin particles can be appropriately selected and are not particularly limited.
[0077]
In the present invention, it is preferable to use a dispersant so that the conductive particles and the fluorine atom-containing resin are not aggregated in a solution containing a compound having a chain polymerizable functional group. Further, it is preferable that the surface of the conductive particles is surface-treated with a fluorine atom-containing compound. By performing the surface treatment, it is possible to improve the dispersibility of the conductive particles and the fluorine atom-containing resin particles in the compound solution, and it is difficult to form secondary particles generated with the lapse of time, and the dispersion stability is improved. Can be further improved.
[0078]
In the present invention, additives such as an antioxidant, an ultraviolet absorber, and a plasticizer can be added to the surface layer as needed.
[0079]
The heat capacity per unit area of the support in the present invention is 0.35 J / cm. ² -K or more, preferably 0.45 J / cm ² -It is K or more. Heat capacity is 0.35 J / cm ² If the temperature is less than K, the temperature of the object to be irradiated during electron beam irradiation cannot be sufficiently controlled, and the remarkable effect of the present invention cannot be obtained. The heat capacity can be controlled by the composition and thickness of the support.
[0080]
The material of the support may be any material as long as it has conductivity, and examples thereof include metals and alloys such as aluminum, stainless steel, nickel, and copper, and paper and plastic that have been subjected to conductive treatment. Among these, aluminum is particularly preferable in terms of productivity, cost, electrical characteristics, stability, and the like. The shape can be arbitrary depending on the electrophotographic apparatus to be applied, such as a cylindrical cylinder or a film, but is preferably cylindrical.
[0081]
When the material is aluminum, the thickness of the support is preferably 1.5 to 4.0 mm. If it is less than 1.5 mm, it is difficult to satisfy the heat capacity of the present invention, and it is difficult to obtain sufficient accuracy. Conversely, if the thickness exceeds 4.0 mm, the heat capacity of the support becomes excessively large and it takes time to raise the temperature during drying to a certain level or more, in addition to the viewpoint of suppressing the cost of the support itself. Makes it difficult to produce.
[0082]
In the present invention, an intermediate layer having a barrier function and an adhesive function can be provided between the support and the photosensitive layer.
[0083]
The intermediate layer is formed for the purpose of improving the adhesiveness of the photosensitive layer, improving the coating properties, protecting the support, covering defects on the substrate, improving the charge injection property from the support, protecting the photosensitive layer against electrical breakdown, etc. You. Examples of the material of the intermediate layer include polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, glue, and gelatin. These are dissolved in a suitable solvent and applied onto a support. The thickness of the intermediate layer is preferably from 0.1 to 2 μm.
[0084]
Examples of the charge generating material used in the present invention include selenium-tellurium, pyrylium dyes, thiapyrylium dyes, various central metals and crystal forms, specifically, phthalocyanines having crystal forms such as α, β, γ, ε, and X types. Pigment, anthantrone pigment, dibenzopyrene quinone pigment, pyranthrone pigment, trisazo pigment, disazo pigment, monoazo pigment, indigo pigment, quinacridone pigment, asymmetric quinocyanine pigment, quinocyanine pigment, amorphous silicon and the like.
[0085]
The charge generating layer is well dispersed with a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill, and the like together with the binder resin and the solvent in a mass ratio of 0.3 to 4 times by mass of the charge generation material. Then, the resultant dispersion is formed by applying and drying the dispersion, or by depositing the above-described charge generating substance. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.1 to 2 μm.
[0086]
The charge transport material used in the present invention is roughly classified into an electron transport material and a hole transport material.
[0087]
Examples of the electron transporting substance include electron-withdrawing substances such as 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, chloranil, and tetracyanoquinodimethane, and these electron-withdrawing substances. Polymerized ones are exemplified.
[0088]
Polycyclic aromatic compounds such as pyrene and anthracene; carbazole, indole, imidazole, oxazole, thiazole, oxadiazole, pyrazole, pyrazoline, thiadiazole, and triazole compounds as hole transport materials Heterocyclic compounds such as p-diethylaminobenzaldehyde-N, N-diphenylhydrazone and N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole; α-phenyl-4′-N, N Styryl compounds such as -diphenylaminostilbene and 5- [4- (di-p-tolylamino) benzylidene] -5H-dibenzo [a, b] cycloheptene; benzidine compounds; triarylmethane compounds; triphenylamine compounds And this Such as a polymer having a group derived from a compound in the main chain or side chain.
[0089]
In addition to these organic charge transport materials, inorganic materials such as selenium, selenium-tellurium, amorphous silicon, and cadmium sulfide can be used. In addition, these charge transporting substances may be used alone or in combination of two or more kinds, and further, a charge transporting substance other than those described above may be used.
[0090]
When the charge transporting layer is a surface layer and contains a resin obtained by curing a charge transporting substance and a compound having a chain polymerizable functional group by electron beam irradiation, the mixing ratio of these is per 100 parts by mass of the resin. It is preferable that the amount of the charge transporting material is 10 to 500 parts by mass.
[0091]
From the viewpoint of electrical and mechanical properties, it is preferable that the compound having a chain polymerizable functional group itself also has a charge transporting function, and that the above-described charge transporting substance is not used.
[0092]
Further, besides the resin obtained by curing a compound having a chain polymerizable functional group by electron beam irradiation, a polycarbonate resin, a polyarylate resin, and a polystyrene resin, as long as the remarkable effects of the present invention can be obtained. And a film-forming resin such as polymethyl methacrylate resin.
[0093]
When the charge transport layer is a surface layer, the thickness is preferably from 1 to 40 μm, and particularly preferably from 5 to 30 μm.
[0094]
When the charge transport layer is not a surface layer but a protective layer is formed on the charge transport layer, the charge transport layer may include a charge transport material and, if necessary, a polycarbonate resin, a polyarylate resin, a polystyrene resin, and a polymethyl methacrylate resin. It contains a film-forming resin. The film thickness at this time is preferably smaller than that in the case where the charge transport layer is the surface layer, specifically, it is preferably 1 to 20 μm, and particularly preferably 5 to 15 μm.
[0095]
When the protective layer formed on the photosensitive layer is a surface layer, the protective layer contains a resin obtained by curing at least a compound having a chain polymerizable functional group by electron beam irradiation.
[0096]
It is preferable that the protective layer has some kind of charge transport function in terms of electrophotographic characteristics. When the above-described charge transport material is contained in the protective layer, the charge transport material contained in the charge transport layer and the charge transport material contained in the protective layer need not be the same. However, as in the case where the charge transport layer is a surface layer, it is preferable that the compound having a chain polymerizable functional group itself also has a charge transport function in terms of both electrical and mechanical properties.
[0097]
Further, as in the case where the charge transport layer is the surface layer, the remarkable effects of the present invention can be obtained in addition to the resin obtained by curing the compound having a chain polymerizable functional group by electron beam irradiation. Within the range, a film-forming resin such as a polycarbonate resin, a polyarylate resin, a polystyrene resin, and a polymethyl methacrylate resin may be contained.
[0098]
The thickness of the protective layer is preferably from 1 to 10 μm, and particularly preferably from 3 to 7 μm.
[0099]
In the electrophotographic process cartridge of the present invention, means and devices capable of realizing a plurality of steps are integrally formed with the electrophotographic photosensitive member, and are provided detachably in the electrophotographic apparatus main body. As long as the configuration includes the electrophotographic photoreceptor of the present invention, the means, apparatus and members to be used can be arbitrarily selected.
[0100]
Further, the electrophotographic apparatus of the present invention forms a latent image corresponding to an image to be formed on the electrophotographic photoreceptor of the present invention, develops the latent image, and displays an image such as plain paper or an OHP sheet. There is no particular limitation as long as the image can be transferred to a recording medium (transfer material). In addition to the above-described electrophotographic photosensitive member, various conventionally known means, devices and members are required. It can be used accordingly.
[0101]
Next, FIG. 2 shows an example of a schematic configuration of an electrophotographic apparatus including the process cartridge of the present invention.
[0102]
In the figure, reference numeral 1 denotes an electrophotographic photosensitive member of the present invention, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow. The electrophotographic photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on the peripheral surface thereof by a charging means 2 during the rotation process, and then is exposed to a light image L (slit exposure, laser beam scanning exposure, etc.) by an image exposure means 3. Receive. As a result, an electrostatic latent image corresponding to the exposure image is sequentially formed on the peripheral surface of the electrophotographic photosensitive member 1. In FIG. 2, a roller charger as a contact charging means is used as the uniform charging means 2 of the electrophotographic photosensitive member 1.
[0103]
The formed electrostatic latent image is developed with toner by a developing unit 4, and the developed toner image is transferred between the electrophotographic photosensitive member 1 and the transfer unit 5 from a feeding unit (not shown) by a transfer unit 5. The transfer material P is sequentially transferred onto the surface of the transfer material P fed in synchronization with one rotation. The transfer material P having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing to be printed out of the apparatus.
[0104]
The surface of the electrophotographic photoreceptor 1 after image transfer is cleaned and cleaned by a cleaning means (cleaning blade) 6 to remove transfer residual toner, and is subjected to static elimination processing by a pre-exposure means 7 to be repeatedly used for image formation. Is done. When the primary charging unit 2 is a contact charging unit as in this example, the pre-exposure unit 7 is not necessarily required.
[0105]
Among the above-mentioned components such as the electrophotographic photosensitive member, the charging unit, the developing unit, and the cleaning unit, a plurality of components are integrally combined as a device unit, and this unit is detachably attached to the device body. Is a process cartridge of the present invention. For example, the electrophotographic photoreceptor 1 and the cleaning means 6 may be integrated into one apparatus unit, and may be configured to be detachable using a guide member such as a rail of the apparatus body. At this time, the above-mentioned device unit may be configured with a charging unit and / or a developing unit. FIG. 2 shows a process cartridge in which the electrophotographic photosensitive member 1, the charging means 2, the developing means 4 and the cleaning means 6 are integrally formed and detachably mounted on the main body of the electrophotographic apparatus. In the present embodiment, each member is integrally supported at a predetermined position by a support member 9, and the support member 9 supporting each member by a guide member 10 provided in the electrophotographic apparatus main body is a process cartridge. It is provided detachably with respect to the apparatus main body.
[0106]
The means necessary for performing a normal electrophotographic process such as the exposure means, the development means, the transfer means and the cleaning means in the present invention is not limited at all, and has no independent cleaning means, so-called cleanerless system. It is also possible to use an electrophotographic apparatus.
[0107]
The present invention is configured as an electrophotographic apparatus provided with the electrophotographic photosensitive member according to the present invention, and is used not only for an electrophotographic copying machine but also for a laser beam printer, a CRT printer, an LED printer, a liquid crystal printer, a laser plate making, and the like. Can be widely used in electrophotographic applications.
[0108]
【Example】
Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not particularly limited thereto.
[0109]
(Example 1)
5 parts of N-methoxymethylated nylon (parts by mass; the same applies hereinafter) was dissolved in 95 parts of methanol to prepare an intermediate layer coating. An aluminum cylinder having an outer diameter of φ30 mm obtained by honing this paint (thickness: 1.50 mm, heat capacity per unit area: 0.366 J / cm) ² -An intermediate layer having a film thickness of 0.65 μm was formed by applying a dip coating method on K) and drying it at 100 ° C. for 20 minutes.
[0110]
3 parts of hydroxygallium phthalocyanine crystal having strong peaks at 7.4 ° and 28.2 ° of black angle 2θ ± 0.2 ° in X-ray diffraction of CuKα, polyvinyl butyral (trade name: Eslek BM2, Sekisui Chemical) 1.5 parts and 35 parts of cyclohexanone were dispersed in a sand mill using a φ1 mm glass bead for 24 hours, and then 60 parts of ethyl acetate was added to prepare a coating for a charge generation layer. This paint was applied on the above-mentioned intermediate layer by a dip coating method and dried at 105 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.18 μm.
[0111]
Next, 4.5 parts of a styryl compound represented by the following structural formula (D-1) and 5.5 parts of a bisphenol Z-type polycarbonate (viscosity average molecular weight: 45,000) are dissolved in 38 g of monochlorobenzene as a charge transporting substance, A coating for the transport layer was prepared. This paint was applied on the charge generation layer by dip coating and dried at 100 ° C. for 60 minutes to form a charge transport layer having a thickness of 12 μm.
[0112]
[Outside 10]

[0113]
Then, the above Compound Example No. 60 parts of a hole transporting compound having a chain polymerizable functional group of No. 9 were dissolved in a mixed solvent of 50 parts of ethanol and 20 parts of isopropyl alcohol to prepare a coating for a protective layer. This paint was applied on the charge transport layer by a dip coating method, dried at 40 ° C. for 10 minutes, and then irradiated with an electron beam using an electron beam irradiation apparatus shown in FIG.
[0114]
The irradiation object is conveyed to a lower portion of the electron beam irradiation window by a belt conveyor, stopped at the irradiation section, and irradiated with the electron beam while rotating the irradiation object (the temperature of the irradiation object at the start of irradiation is 25 ° C.). ), After the irradiation is completed, it is again conveyed and carried out. At this time, the effective electron beam irradiation width in the electron beam irradiation part (the width of 1 / e or more of the peak position in the electron beam density distribution on the surface of the irradiation object) was 4 cm. The electron beam irradiation condition is such that the electron beam absorbed dose rate is 1 × 10 ⁶ Gy / sec (electron beam absorbed dose within the effective electron beam irradiation width / time during which the surface of the irradiated object is within the effective electron beam irradiation width), the acceleration voltage is 150 kV, and the electron beam absorbed dose (electron beam irradiation process) Medium, the total absorbed dose received by the irradiated object in the effective electron beam irradiation width) is 2 × 10 ⁵ Gy. The time from the start to the end of electron beam irradiation was 1.5 seconds. By irradiating an electron beam under the above conditions and curing the compound having a chain polymerizable functional group, a protective layer having a thickness of 5 μm was formed, and an electrophotographic photosensitive member was obtained.
[0115]
The drum photoreceptor test device (trade name: Cynthia-59, manufactured by Gentec Co., Ltd.) was used to measure unevenness in the longitudinal direction of the electrophotographic photoreceptor in the electrophotographic photoreceptor thus obtained. Was measured by the following method. The remaining portion other than 15 mm from both ends of the electrophotographic photoreceptor was considered to be an effective portion of the electrophotographic photoreceptor, and the potential was measured at five locations where the effective portion was equally divided in the longitudinal direction. The measurement points from the lower end side during the dip coating were (a), (b), (c), (d) and (e).
[0116]
First, the electrophotographic photoreceptor was contact-charged using the same charging roller as that included in LASER SHOT LBP-930 (manufactured by Canon). At this time, at the position (c) in the center of the electrophotographic photosensitive member, the dark portion potential V at the potential probe position ₀ Was controlled to −650 V (the rotation speed of the drum was set to 60 rpm). Using a halogen lamp as a light source, irradiating monochromatic light (775 nm) with a filter, and calculating an exposure amount (Vl) necessary for reducing the surface potential of the electrophotographic photosensitive member to -200 (V), Sensitivity.
[0117]
Next, after charging / exposure, a light emitting diode having a wavelength of 700 nm ² A pre-exposure step of removing the electricity by giving the energy was performed, and the surface potential of the electrophotographic photoreceptor after the pre-exposure was defined as a residual potential (Vr).
[0118]
For the remaining four portions other than (c) in the center of the electrophotographic photosensitive member, the dark portion potential V in the center (c). ₀ Is charged at the same bias voltage as was controlled so as to be -650 V, and after irradiating the same exposure amount as obtained for the sensitivity at the center (c), the residual potential was obtained at the center (c). The same pre-exposure is performed, the surface potential of the electrophotographic photosensitive member at each location is measured, and the absolute value of the difference between each potential and the central part (c) is determined by ΔV ₀ , ΔVl and ΔVsl.
[0119]
Table 2 shows the obtained results.
[0120]
Next, this electrophotographic photoreceptor was mounted on a laser beam printer modified with LASER SHOT LBP-930 (manufactured by Canon) so that the development volume could be adjusted variably, and was subjected to normal temperature and normal humidity (23 ° C., 55% RH, N / N), the charging condition is set so that the initial dark portion potential (Vd) becomes -650 (V), and a laser beam having a wavelength of 780 (nm) is applied thereto to reduce the potential of -650 (V) to-. The light amount (bright portion potential Vl) required to reduce the voltage to 170 (V) was measured and defined as sensitivity. Furthermore, 20 (μJ / cm ² The initial characteristics were measured with the potential when the light amount of (1) was applied as the residual potential (Vr). In the other conditions, the transfer current was +5.5 μA, and the process speed was 106 mm / sec. The potential was measured only at the drum center (c).
[0121]
The environment was changed to low temperature and low humidity (15 ° C./10%, L / L) and high temperature and high humidity (32 ° C./80%, H / H), and the initial dark portion potential (Vd) became -650 (V). The charging conditions were set so that the light amount was the same as the amount of exposure required to lower the voltage to -170 (V) under the normal temperature and normal humidity. The absolute value of the amount of change from -170 (V), which is the partial potential, was defined as ΔVl.
[0122]
Further, the electrophotographic photoreceptor prepared in the same manner as above was mounted on the same laser beam printer as above, and the continuous paper endurance of 10,000 sheets under normal temperature and low humidity (23 ° C., 10% RH, N / L) was carried out. △ Vd and △ Vl were measured for the amount of change in the dark portion potential and the bright portion potential at the initial stage and immediately after the endurance. The initial potential setting was the same as above, with the dark part potential set to -650 (V) and the light part potential set to -170 (V).
[0123]
Further, the shaving amount of the electrophotographic photosensitive member caused by the paper passing durability test was measured using an eddy current film thickness meter (manufactured by Karl Fischer). The measurement was performed at arbitrary 10 points in the longitudinal direction of the electrophotographic photosensitive member, and the average value thereof was defined as the amount of shaving.
[0124]
In addition, the electrophotographic photosensitive member prepared in the same manner as above was mounted on the same laser beam printer as above, and the dark area potential was set to -650 V under normal temperature and normal humidity (23 ° C./55% RH, N / N). The bright part potential was set to -170 V, and the degree of ghost was evaluated as follows.
[0125]
First, after outputting an appropriate character image (5 points) for one round of the electrophotographic photoreceptor, a halftone image having a dot density of 1 dot and 1 space and an entire black image are output to determine whether a ghost phenomenon has occurred. confirmed. Next, after continuously outputting an image in which a line having a width of about 2 mm is present every 7 mm in length and width, a halftone image and a full black image with a dot density of one dot and one space are output, and a ghost phenomenon occurs. I checked whether it was.
[0126]
The output was sampled at F5 (center value) and F9 (light density) of the developing volume of the laser beam printer, respectively. The evaluation criterion is that in both F5 and F9, the halftone image and the entire black image in which no ghost is generated are ranked 5, and when the halftone image is output in F9, the ghost is generated but the entire black image is evaluated. When output, no ghost was generated, rank 4 was given. When a halftone image was output at F5, ghost was generated, but when a full black image was output, no ghost was output rank 3. , F9 when a ghost image was generated even when a full black image was output, and F5 when a ghost image was generated even when a full black image was output was ranked 1.
[0127]
The results are shown in Table 3 below.
[0128]
(Examples 2 to 13)
As shown in Table 1 below, the heat capacity per unit area of the support is changed by changing the thickness and the material of the support, and the rotation speed and irradiation time of the object to be irradiated at the time of electron beam irradiation, and electron beam irradiation are performed. An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the electron beam absorption dose rate was changed by adjusting the beam current value and the acceleration voltage at the time. The results are shown in Tables 2 and 3.
[0129]
(Examples 14 to 20)
Compound No. used in the protective layer of Example 1 Compound No. 9 having a hole-transporting compound having a chain polymerizable functional group Electrophotographic photoreceptor in the same manner as in Example 1 except that the heat capacity per unit area of the support and the electron beam absorption dose rate were changed as in Examples 2 to 13 in place of the compound of Example 12. Was created and evaluated. The results are shown in Tables 2 and 3.
[0130]
(Examples 21 to 22)
For each of the aluminum pipes having different thicknesses whose surfaces are mirror-polished, 30 g of a degreasing agent (trade name: NG- # 30, manufactured by Kizai Co., Ltd.) is dissolved in 1000 g of water at 60 ° C. for 5 minutes. Washing was performed. Next, each aluminum tube was washed with water, immersed in 7% nitric acid at 25 ° C. for 1 minute, and further washed with water. Then, in a 180 g / l sulfuric acid electrolyte (dissolved aluminum ion concentration: 7 g / l), 1.2 A / dm ² And an anodic oxide film having an average film thickness of 7 μm was formed. Then, after washing with water, immersed in an aqueous solution in which 10 g of a high-temperature sealing agent containing nickel acetate as a main component (Top Seal DX-500, manufactured by Okuno Pharmaceutical Co., Ltd.) was dissolved in 1 liter of water at 95 ° C. for 30 minutes, and sealed. The holes were treated. Further, it was subjected to an ultrasonic cleaning treatment and dried.
[0131]
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 14, except that the thus obtained support was used. The results are shown in Tables 2 and 3.
[0132]
(Example 23)
The paint for the conductive layer was prepared in the following procedure. 50 parts of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide, 25 parts of phenolic resin, 20 parts of methyl cellosolve, 5 parts of methanol, and a silicone compound (polydimethylsiloxane polyoxyalkylene copolymer, average 0.002 parts of (molecular weight: 3000) were dispersed and adjusted by a sand mill using glass beads having a diameter of 1 mm for 2 hours.
[0133]
Aluminum base tube with an outer diameter of φ30 mm as a support (heat capacity per unit area: 0.486 J / cm ² Using K), the obtained coating material for a conductive layer is applied on a support by a dip coating method, and dried at 150 ° C. for 30 minutes to form a 12 μm-thick conductive layer. An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 14 except that an intermediate layer was provided. The results are shown in Tables 2 and 3.
[0134]
(Example 24)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 3, except that the temperature of the object to be irradiated at the start of electron beam irradiation was 40 ° C. The results are shown in Tables 2 and 3.
[0135]
(Example 25)
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 3 except that the temperature of the object to be irradiated at the start of electron beam irradiation was 70 ° C. The results are shown in Tables 2 and 3.
[0136]
(Example 26)
Compound No. used in the protective layer of Example 3 Compound Example No. 9 was prepared using 60 parts of a hole transporting compound having a chain polymerizable functional group of Compound No. Compound No. 15 and Compound Example No. 15 An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 3, except that 15 parts of Compound 34 was used. The results are shown in Tables 2 and 3.
[0137]
(Examples 27 to 28)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Examples 2 to 13 except that the electron beam absorption dose rate was changed as shown in Table 1. The results are shown in Tables 2 and 3.
[0138]
(Examples 29 to 30)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Examples 2 to 13 except that the electron beam absorption dose rate and the acceleration voltage were changed as shown in Table 1. The results are shown in Tables 2 and 3.
[0139]
[Table 1]

[0140]
[Table 2]

[0141]
[Table 3]

[0142]
[Table 4]

[0143]
[Table 5]

[0144]
[Table 6]

[0145]
(Comparative Examples 1 to 7)
As shown in Table 6 below, the heat capacity per unit area of the support is changed by changing the film thickness and the material of the support, and the rotation speed, irradiation time, An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the electron beam absorption dose rate was changed by adjusting the beam current value and the acceleration voltage during irradiation. The results are shown in Tables 5 and 6.
[0146]
(Comparative Examples 8 to 9)
As shown in Table 4 below, an electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 14 except that the heat capacity per unit area of the support and the electron beam absorption dose rate were changed. The results are shown in Tables 5 and 6.
[0147]
(Comparative Example 10)
1 × 10 electron beam absorbed dose rate ⁸ An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 21 except that Gy / sec was changed. The results are shown in Tables 5 and 6.
[0148]
(Comparative Example 11)
The heat capacity per unit area of the support is 0.335 J / cm ² An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 23 except that K was changed. The results are shown in Tables 5 and 6.
[0149]
(Comparative Example 12)
1 × 10 electron beam absorbed dose rate ⁸ An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 23 except that Gy / sec was changed. The results are shown in Tables 5 and 6.
(Comparative Example 13)
7 × 10 electron beam absorbed dose rate ² An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 29 except that Gy / sec was changed. The results are shown in Tables 5 and 6.
[0150]
[Table 7]

[0151]
[Table 8]

[0152]
[Table 9]

[0153]
(Example 31)
5 parts of alcohol-soluble copolymerized nylon (trade name: Amilan CM-8000, manufactured by Toray Industries, Inc.) was dissolved in 95 parts of methanol to prepare a coating for an intermediate layer. An aluminum cylinder with an outer diameter of φ30 mm obtained by cutting this paint (thickness: 1.50 mm, heat capacity per unit area: 0.366 J / cm) ² -An intermediate layer having a thickness of 0.8 μm was formed by applying a dip coating method on K) and drying it at 120 ° C. for 60 minutes.
[0154]
1.2 parts of oxytitanium phthalocyanine crystal having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 28.2 ° of black angle 2θ ± 0.2 ° in X-ray diffraction of CuKα, polyvinyl butyrate Lar (trade name: ESLEC BX-1, manufactured by Sekisui Chemical Co., Ltd.) 1.0 part and cyclohexanone 35 parts were dispersed for 3 hours by a sand mill using a φ1 mm glass bead, and then 60 parts of tetrahydrofuran was added. In addition, a paint for a charge generation layer was prepared. This paint was applied on the above-mentioned intermediate layer by a dip coating method, and dried at 105 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.15 μm.
[0155]
Next, Compound Example No. 1 was used as a charge transport material. 60 parts of the compound No. 18 were dissolved in 40 parts of chlorobenzene and 10 parts of dichloromethane to prepare a charge transport layer coating. This liquid was applied onto the charge generation layer by dip coating, dried at 50 ° C. for 15 minutes, and then irradiated with an electron beam using the same electron beam irradiation apparatus as in Example 1. The irradiation conditions are shown in Table 7.
[0156]
Further, the obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. The results are shown in Tables 8 and 9.
[0157]
(Examples 32-39)
As shown in Table 7 below, the heat capacity per unit area of the support is changed by changing the film thickness of the support, and the rotation speed and irradiation time of the irradiation target at the time of electron beam irradiation, and at the time of electron beam irradiation, An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 31, except that the electron beam absorption dose rate was changed by adjusting the beam current value and the acceleration voltage. The results are shown in Tables 8 and 9.
[0158]
(Example 40)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 31, except that the charge generation layer of Example 31 was formed as described below. The results are shown in Tables 8 and 9.
[0159]
3 parts of an azo pigment represented by the following structural formula (P-1) and 2 parts of a polyvinyl butyral resin (butyralization degree: 65 mol%, number average molecular weight: 30,000) were added to 80 parts of cyclohexanone, and dispersed together with glass beads by a sand mill for 15 hours. The mixture was diluted with 80 parts of tetrahydrofuran. The obtained solution was applied on the intermediate layer by a dip coating method, and dried to form a charge generation layer having a thickness of 0.15 μm.
[0160]
[Outside 11]

[0161]
(Example 41)
The heat capacity per unit area of the support is 0.608 J / cm. ² An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 40 except that K was changed to K. The results are shown in Tables 8 and 9.
[0162]
(Example 42)
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 35 except that the absorbed dose rate in Example 35 was changed as shown in Table 7 below. The results are shown in Tables 8 and 9.
[0163]
[Table 10]

[0164]
[Table 11]

[0165]
[Table 12]

[0166]
(Comparative Examples 14 to 18)
As shown in Table 10 below, the heat capacity per unit area of the support was changed by changing the film thickness of the support, the rotation speed of the irradiated object during electron beam irradiation, and the beam current during electron beam irradiation. An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 31 except that the electron beam absorption dose rate was changed by adjusting the value and the acceleration voltage. The results are shown in Tables 11 and 12.
[0167]
(Comparative Example 19)
The heat capacity per unit area of the support is 0.292 J / cm ² An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 39 except that K was changed. The results are shown in Tables 11 and 12.
[0168]
(Comparative Example 20)
The heat capacity per unit area of the support is 0.292 J / cm ² An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 40 except that K was changed to K. The results are shown in Tables 11 and 12.
[0169]
(Comparative Example 21)
5 × 10 electron beam absorbed dose rate ⁷ An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Comparative Example 20, except that Gy / sec was changed. The results are shown in Tables 11 and 12.
[0170]
(Comparative Example 22)
5 × 10 electron beam absorbed dose rate ² An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 42 except that Gy / sec was changed. The results are shown in Tables 11 and 12.
[0171]
[Table 13]

[0172]
[Table 14]

[0173]
[Table 15]

[0174]
【The invention's effect】
As described above, according to the present invention, not only has excellent mechanical durability, but also has excellent sensitivity, increase in residual potential, uneven sensitivity, uneven charging, various memories, and potential fluctuation during repeated use. It has become possible to provide an electrophotographic photoreceptor having extremely excellent characteristics, in which changes in electrophotographic characteristics are unlikely to occur, a process cartridge including the electrophotographic photoreceptor, and an electrophotographic apparatus.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a schematic configuration of an electron beam irradiation apparatus used when producing an electrophotographic photosensitive member of the present invention.
FIG. 2 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge of the present invention.
[Explanation of symbols]
1. Electrophotographic photoreceptor of the present invention
1 'Irradiated object
2 Charging means
3. Image exposure means
4 Developing means
5 transfer means
6 Cleaning blade
7 Pre-exposure means
8 Image fixing means
9 Transfer material transfer device
10 Supporting members
10 'guide member
11 Electron beam generator
12 Terminal
12a filament
12b house
12c grid
14 Accelerator tube
20 Irradiation room
22 Irradiation space
30 Irradiation window
32 window foil
34 Window frame structure
100 support members
110 Guide member
L Light image exposure
P transfer material

Claims (8)

An electrophotographic photoreceptor having a photosensitive layer on a support, wherein the electrophotographic photoreceptor has a surface layer containing a resin obtained by curing a compound having a chain polymerizable functional group by electron beam irradiation, The heat capacity per unit area of the support is 0.35 J / cm ² · K or more, and the electron beam absorption dose rate on the surface of the irradiation object in irradiation with the electron beam is 1 × 10 ³ to 2 × 10 ^7. An electrophotographic photosensitive member characterized by Gy / sec. 2. The electrophotographic photoreceptor according to claim 1, wherein the electron beam absorbed dose rate is 1 × 10 ⁴ to 2 × 10 ⁶ Gy / sec. 3. The electrophotographic photoreceptor according to claim 1, wherein the heat capacity per unit area of the support is 0.45 J / cm ² · K or more. The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the absorbed dose of the electron beam is 1 x 10 ^{3 to} 5 x 10 ⁵ Gy. The electrophotographic photosensitive member according to claim 1, wherein an acceleration voltage of the electron beam is 5 × 10 ⁴ to 2 × 10 ⁵ V. The electrophotographic photosensitive member according to claim 1, wherein the irradiation time of the electron beam is 5 seconds or less. An electrophotographic photosensitive member according to any one of claims 1 to 6, and at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit are integrally supported, and are detachably attached to an electrophotographic apparatus main body. A process cartridge, comprising: An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an exposing unit, a developing unit, and a transferring unit.

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