JP3823852B2 - Electrophotographic photosensitive member manufacturing method, electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus - Google Patents

Description

【００９１】
上記の式（１）〜（６）中、クロロガリウムフタロシアニンとしては、Cukα線を用いたX線回折スペクトルにおいて、ブラッグ角度(2θ±0.2°)の値が7.4°,16.6°,25.5°,28.3°である位置に回折ピークを少なくとも有するものが好ましい。また、チタニルフタロシアニンとしては、Cukα線を用いたX線回折スペクトルにおいて、ブラッグ角度(2θ±0.2°)の値が9.6°,24.1°,27.3°である位置に回折ピークを少なくとも有し、最大ピークを27.3°に有するものが好ましい。
【００９２】
また、下記式（１）〜（６）に示されるフタロシアニン顔料以外に、式（４）の配位中心となるＧａに結合しているＣｌ原子を−ＯＨ基に置換したヒドロキシガリウムフタロシアニンも好ましい。このようなヒドロキシガリウムフタロシアニンとしては、Cukα線を用いたX線回折スペクトルにおいて、ブラッグ角度(2θ±0.2°)の値が7.5°,9.9°,12.5°,16.3°,18.6°, 25.1°,28.1°である位置に回折ピークを少なくとも有するものが好ましい。
【００９３】
更に、このような顔料は、公知の方法で製造される顔料結晶を、自動乳鉢、遊星ミル、振動ミル、CFミル、ローラーミル、サンドミル、ニーダー等で機械的に乾式粉砕するか、乾式粉砕後、溶剤と共にボールミル、乳鉢、サンドミル、ニーダー等を用いて湿式粉砕処理を行うことによって製造することができる。
【００９４】
上記の湿式粉砕処理において使用される溶剤としては、芳香族類(トルエン、クロロベンゼン等)、アミド類(ジメチルホルムアミド、N-メチルピロリドン等)、脂肪族アルコール類(メタノール、エタノール、ブタノール等)、脂肪族多価アルコール類(エチレングリコール、グリセリン、ポリエチレングリコール等)、芳香族アルコール類(ベンジルアルコール、フェネチルアルコール等)、エステル類(酢酸エステル、酢酸ブチル等)、ケトン類(アセトン、メチルエチルケトン等)、ジメチルスルホキシド、エーテル類(ジエチルエーテル、テトラヒドロフラン等)、さらには数種の混合系、水とこれら有機溶剤の混合系が挙げられる。
【００９５】
また、この溶剤は、顔料結晶に対して、１〜２００質量部、好ましくは１０〜１００質量部の範囲で使用する。更に、処理温度は、０℃〜溶剤の沸点、好ましくは１０〜６０℃の範囲で行う。また、粉砕の際に食塩、ぼう硝等の磨砕助剤を用いることもできる。
【００９６】
そして磨砕助剤は顔料に対し0.5〜20倍、好ましくは1〜10倍用いればよい。また、公知の方法で製造される顔料結晶を、アシッドペースティングあるいはアシッドペースティングと前述したような乾式粉砕あるいは湿式粉砕を組み合わせることにより、結晶制御することもできる。
【００９７】
アシッドペースティングに用いる酸としては、硫酸が好ましく、濃度（質量パーセント濃度）７０〜１００%、好ましくは９５〜１００%のものが使用され、溶解温度は、−２０〜１００℃好ましくは−２０〜６０℃の範囲に設定される。濃硫酸の量は、顔料結晶の重量に対して、１〜１００倍、好ましくは３〜５０倍の範囲に設定される。析出させる溶剤としては、水あるいは、水と有機溶剤の混合溶剤、アンモニア水等が任意の量で用いられる。析出させる温度については特に制限はないが、発熱を防ぐために、氷等で冷却することが好ましい。
【００９８】
また、顔料の含有量は、電荷発生層１の全質量に対して、１０〜９０質量％であることが好ましく、４０〜７０質量％であることがより好ましい。顔料の含有量がそれぞれ上記の数値範囲の下限値未満となると、十分な感度が得られにくくなる。一方、顔料の含有量がそれぞれ上記の数値範囲の上限値を超えると、帯電性の低下、感度の低下などの弊害が発生する傾向が大きくなる。
【００９９】
電荷発生層１に含有されるバインダー樹脂は、絶縁性樹脂であれば特に限定されるものではなく、広範な絶縁性樹脂から選択して使用することができる。例えば、好ましいバインダー樹脂としては、ポリビニルアセタール樹脂、ポリアリレート樹脂(ビスフェノールAとフタル酸の重縮合体等)、ポリカーボネート樹脂、ポリエステル樹脂、フェノキシ樹脂、塩化ビニル-酢酸ビニル共重合体、ポリアミド樹脂、アクリル樹脂、ポリアクリルアミド樹脂、ポリビニルピリジン樹脂、セルロース樹脂、ウレタン樹脂、エポキシ樹脂、カゼイン、ポリビニルアルコール樹脂、ポリビニルピロリドン樹脂等の絶縁性樹脂をあげることができる。
【０１００】
電荷発生層１用のバインダー樹脂としては、顔料の分散性の観点から、特にポリビニルアセタール樹脂及び塩化ビニル−酢酸ビニル共重合体が好ましく用いられる。なお、上記のバインダー樹脂は、単独あるいは2種以上を混合して用いてもよい。
【０１０１】
また、顔料とバインダー樹脂との配合比(質量比)は、電荷発生層１の場合、10:1〜1:10の範囲が好ましい。顔料の質量に対してバインダー樹脂の質量が上記の配合比で示される値未満となると、成膜性が悪くなる等の弊害が発生する傾向が大きくなる。一方、顔料の質量に対してバインダー樹脂の質量が上記の配合比で示される値を超えると、膜中の含有量が相対的に少なくなるため十分な感度が得られなくなる傾向が大きくなる。
【０１０２】
更に、電荷発生層１を形成するための塗布液に含まれる有機溶剤は、バインダー樹脂を溶かす事ができる溶剤であり、かつ、顔料（電荷発生物質）の結晶型を変化させる影響を及ぼさないものであれば特に限定されるものではなく、公知の有機溶剤を使用することができる。
【０１０３】
例えば、アルコール系、芳香族系、ハロゲン化炭化水素系、ケトン系、ケトンアルコール系、エーテル系、エステル系等から任意で選択することができる。具体的には、例えば、メタノール、エタノール、n-プロパノール、iso-プロパノール、n-ブタノール、ベンジルアルコール、メチルセルソルブ、エチルセルソルブ、アセトン、メチルエチルケトン、シクロヘキサノン、酢酸メチル、酢酸エチル、酢酸n-ブチル、ジオキサン、テトラヒドロフラン、メチレンクロライド、クロロホルム、クロロベンゼン、トルエン等の通常の有機溶剤を用いることができる。そして、これらの有機溶剤は単独あるいは2種以上混合して用いることができる。
【０１０４】
この電荷発生層１には、その電気特性の向上、画質向上などのために下引層４の説明において記載したものと同じ他の添加剤を添加することもできる。
【０１０５】
更に、電荷発生層１の層厚は、良好な電気特性と画質を与えるために、０．０５〜５μｍであることが好ましく、０．１〜１μｍであることがより好ましい。電荷発生層１の厚みが０．０５μｍ未満であると、十分な感度を与えることができない。一方、電荷発生層１の厚みが５μｍを超えると、帯電性の不良などの弊害を生じさせ易い。
【０１０６】
電荷発生層１は、顔料（電荷発生物質）、有機溶剤、バインダー樹脂、添加剤（例えば、顔料の分散助剤等）等を混合して塗布液を調製し、これを下引層４上に塗布して更に乾燥させることにより形成することができる。また、電荷発生層１は、電荷発生物質を下引層４上に真空蒸着することによっても形成することができる。
【０１０７】
電荷発生層１の形成用の塗布液を調製するには、顔料、バインダー樹脂、有機溶剤、その他の添加剤（例えば、顔料の分散助剤等）等とともに混合する。顔料を液中に高分散させる方法としては、ロールミル、ボールミル、振動ボールミル、アトライター、サンドミル、コロイドミル、ペイントシェーカーなどの分散方法を用いることができる。
【０１０８】
更に、成膜性の観点から、電荷発生層１を形成するための塗布液に含まれる顔料などの分散粒子の粒子径は、0.5μm以下であることが好ましく、0.3μm以下であることがより好ましく、0.15μm以下であることが更に好ましい。分散粒子の粒子径が0.5μmを超えると、電荷発生層１の成膜性が悪くなり、画質欠陥を生じ易い。
【０１０９】
電荷発生層１の形成用の塗布液を下引層４上に塗布する場合の塗布方法としては、ブレードコーティング法、ワイヤーバーコーティング法、スプレーコーティング法、浸漬コーティング法、ビードコーティング法、エアーナイフコーティング法、カーテンコーティング法等の通常の方法を用いることができる。
【０１１０】
次に電荷輸送層２について説明する。電荷輸送層２に含有される電荷輸送物質は、特に限定されるものではなく、公知の物質を使用することができる。
【０１１１】
例えば、2,5-ビス(p-ジエチルアミノフェニル)-1,3,4-オキサジアゾール等のオキサジアゾール誘導体、1,3,5-トリフェニル-ピラゾリン、1-[ピリジル-(2)]-3-(p-ジエチルアミノスチリル)-5-(p-ジエチルアミノスチリル)ピラゾリン等のピラゾリン誘導体、トリフェニルアミン、トリ(P-メチル)フェニルアミン、N,N’-ビス(3,4-ジメチルフェニル)ビフェニル-4-アミン、ジベンジルアニリン、9,9-ジメチル-N,N’-ジ(p-トリル)フルオレノン-2-アミン等の芳香族第3級アミノ化合物、N,N’-ジフェニル-N,N’-ビス(3-メチルフェニル)-[1,1-ビフェニル]-4,4’-ジアミン等の芳香族第3級ジアミノ化合物、3-(4’ジメチルアミノフェニル)-5,6-ジ-(4’-メトキシフェニル)-1,2,4-トリアジン等の1,2,4-トリアジン誘導体、4-ジエチルアミノベンズアルデヒド-1,1-ジフェニルヒドラゾン、4-ジフェニルアミノベンズアルデヒド-1,1-ジフェニルヒドラゾン、[p-(ジエチルアミノ)フェニル](1-ナフチル)フェニルヒドラゾンなどのヒドラゾン誘導体、2-フェニル-4-スチリル-キナゾリン等のキナゾリン誘導体、6-ヒドロキシ-2,3-ジ(p-メトキシフェニル)-ベンゾフラン等のベンゾフラン誘導体、p-(2,2-ジフェニルビニル)-N,N’-ジフェニルアニリン等のα-スチルベン誘導体、エナミン誘導体、N-エチルカルバゾール等のカルバゾール誘導体、ポリ-N-ビニルカルバゾール及びその誘導体等の正孔輸送物質、クロラニル、ブロモアニル、アントラキノン等のキノン系化合物、テトラシアノキノジメタン系化合物、2,4,7-トリニトロフルオレノン、2,4,5,7-テトラニトロ-9-フルオレノン等のフルオレノン化合物、2-(4-ビフェニル)-5-(4-t-ブチルフェニル)-1,3,4-オキサジアゾール、2,5-ビス(4-ナフチル)-1,3,4-オキサジアゾール、2,5-ビス(4-ジエチルアミノフェニル)1,3,4オキサジアゾール等のオキサジアゾール系化合物、キサントン系化合物、チオフェン化合物、3,3',5,5'テトラ-t-ブチルジフェノキノン等のジフェノキノン化合物などの電子輸送物質等が挙げられる。
【０１１２】
更には、電荷輸送物質は、以上例示した化合物の基本構造を主鎖又は側鎖に有する重合体等も挙げられる。そして、これらの電荷輸送材料は、1種又は2種以上を組み合せて使用することもできる。
【０１１３】
また、電荷輸送層２に含有されるバインダー樹脂は特に限定されるものではなく、公知のものを使用することができるが、電機絶縁性のフィルムを形成することが可能な樹脂が好ましい。
【０１１４】
例えば、ポリカーボネート樹脂、ポリエステル樹脂、メタクリル樹脂、アクリル樹脂、ポリ塩化ビニル樹脂、ポリ塩化ビニリデン樹脂、ポリスチレン樹脂、ポリビニルアセテート樹脂、スチレンーブタジエン共重合体、塩化ビニリデンーアクリロニトリル共重合体、塩化ビニル-酢酸ビニル共重合体、塩化ビニル-酢酸ビニル-無水マレイン酸共重合体、シリコン樹脂。シリコン−アルキッド樹脂、フェノールーホルムアルデヒド樹脂、スチレンーアルキッド樹脂、ポリ−Ｎ−カルバゾール、ポリビニルブチラール、ポリビニルフォルマール、ポリスルホン、カゼイン、ゼラチン、ポリビニルアルコール、エチルセルロース、フェノール樹脂、ポリアミド、カルボキシーメチルセルロース、塩化ビニリデン系ポリマーワックス、ポリウレタン等が挙げられる。
【０１１５】
そして、これらのバインダー樹脂は、単独又は2種類以上混合して用いることができる。特に、ポリカーボネート樹脂、ポリエステル樹脂、メタクリル樹脂、アクリル樹脂が電荷輸送物質との相溶性、溶剤への溶解性、強度の点で優れているので好ましく用いられる。
【０１１６】
また、バインダー樹脂と電荷輸送物質との配合比(質量比)は電気特性低下、膜強度低下に考慮しつつ任意に設定することができる。この電荷輸送層２の層厚は5〜50μmであることが好ましく、10〜35μmであることがより好ましい。が適当である。
【０１１７】
電荷輸送層２は、電荷輸送物質、有機溶剤、バインダー樹脂等を混合して塗布液を調製し、これを電荷発生層１上に塗布して更に乾燥させることにより形成することができる。
【０１１８】
電荷輸送層２の形成用の塗布液を調製するには、電荷輸送物質、有機溶剤、バインダー樹脂等とともに混合する。電荷輸送物質を液中に高分散させる方法としては、ロールミル、ボールミル、振動ボールミル、アトライター、サンドミル、コロイドミル、ペイントシェーカーなどの分散方法を用いることができる。
【０１１９】
更に、成膜性の観点から、電荷輸送層２を形成するための塗布液に含まれる顔料などの分散粒子の粒子径は、0.5μm以下であることが好ましく、0.3μm以下であることがより好ましく、0.15μm以下であることが更に好ましい。分散粒子の粒子径が0.5μmを超えると、電荷輸送層２の成膜性が悪くなり、画質欠陥を生じ易い。
【０１２０】
更に、電荷輸送層２の形成用の塗布液に用いる溶剤としては、ジオキサン、テトラヒドロフラン、メチレンクロライド、クロロホルム、クロロベンゼン、トルエン等の通常の有機溶剤を単独あるいは2種以上混合して用いることができる。
【０１２１】
電荷輸送層２の塗布方法としては、ブレードコーティング法、ワイヤーバーコーティング法、スプレーコーティング法、浸漬コーティング法、ビードコーティング法、エアーナイフコーティング法、カーテンコーティング法等の通常の方法を用いることができる。
【０１２２】
［第二実施形態］
図２は、本発明の電子写真感光体の第二実施形態を示す断面図である。図２に示す電子写真感光体１１０は、感光層６を単層構造とした以外は図１に示した電子写真感光体１００と同様の構成を有する。
【０１２３】
図２に示す感光層６は、図１に示した電荷発生層１と電荷輸送層２に含有される電荷発生物質と電荷輸送物質をはじめとする物質を合わせて含有する層である。
【０１２４】
感光層６がこのように単層型の場合には、顔料の含有量は、感光層６の全質量に対して、０．１〜５０質量％であることが好ましく、１〜２０質量％であることがより好ましい。また、顔料の含有量が上記の数値範囲の下限値未満となると、十分な感度が得られにくくなる。一方、顔料の含有量が上記の数値範囲の上限値を超えると、帯電性の低下、感度の低下などの弊害が発生する傾向が大きくなる。
【０１２５】
また、このように感光層６が単層型の場合、バインダー樹脂としては、正孔輸送性材料との相溶性の観点から、特にポリカーボネート樹脂及びメタクリル樹脂が好ましく用いられる。更に、これらの樹脂のポリ-N-ビニルカルバゾール、ポリビニルアントラセン、ポリビニルピレン、ポリシランなどの有機光導電性ポリマーの中から選択して使用してもよい。なお、上記のバインダー樹脂は、単独あるいは2種以上を混合して用いてもよい。
【０１２６】
この感光層６も、上述した電荷輸送物質、上述した電荷輸送物質、上述した有機溶剤、バインダー樹脂等を混合して塗布液を調製し、上述と同様の方法により導電性支持体層３上に塗布して更に乾燥させることにより形成することができる。
【０１２７】
［第三実施形態］
図３は、本発明の電子写真感光体の第三実施形態を示す断面図である。図３に示す電子写真感光体１２０は、感光層６上に保護層５を備えること以外は図１に示した電子写真感光体１００と同様の構成を有する。
【０１２８】
保護層５は、電子写真感光体１２０の帯電時の電荷輸送層２の化学的変化を防止したり、感光層６の機械的強度をさらに改善する為に用いられる。この保護層５は、導電性材料を適当なバインダー樹脂中に含有させた塗布液を感光層６上に塗布することにより形成される。
【０１２９】
この導電性材料は特に限定されるものではなく、例えば、N,N'-ジメチルフェロセン等のメタロセン化合物、N,N'-ジフェニル-N,N'-ビス(3-メチルフェニル)-[1,1'-ビフェニル]-4,4'-ジアミン等の芳香族アミン化合物、酸化モリブデン、酸化タングステン、酸化アンチモン、酸化錫、酸化チタン、酸化インジウム、酸化錫とアンチモン、硫酸バリウムと酸化アンチモンとの固溶体の担体、上記金属酸化物の混合物、酸化チタン、酸化スズ、酸化亜鉛又は硫酸バリウムの単一粒子中に上記の金属酸化物を混合したもの、或いは、酸化チタン、酸化スズ、酸化亜鉛又は硫酸バリウムの単一粒子中に上記の金属酸化物を被覆したものが挙げられる。
【０１３０】
この保護層５に用いるバインダー樹脂としては、ポリアミド樹脂、ポリビニルアセタール樹脂、ポリウレタン樹脂、ポリエステル樹脂、エポキシ樹脂、ポリケトン樹脂、ポリカーボネート樹脂、ポリビニルケトン樹脂、ポリスチレン樹脂、ポリアクリルアミド樹脂、ポリイミド樹脂、ポリアミドイミド樹脂等の公知の樹脂が用いられる。また、これらは必要に応じて互いに架橋させて使用することもできる。
【０１３１】
保護層５の厚みは１〜２０μmであることが好ましく、２〜１０μmであることがより好ましい。この保護層５を形成するための塗布液の塗布方法としては、ブレードコーティング法、ワイヤーバーコーティング法、スプレーコーティング法、浸漬コーティング法、ビードコーティング法、エアーナイフコーティング法、カーテンコーティング法等の通常の方法を用いることができる。
【０１３２】
また、保護層５を形成するための塗布液に用いる溶剤としては、ジオキサン、テトラヒドロフラン、メチレンクロライド、クロロホルム、クロロベンゼン、トルエン等の通常の有機溶剤を単独あるいは2種以上混合して用いることができるが、できるだけこの塗布液が塗布される感光層６を溶解しにくい溶剤を用いることが好ましい。
【０１３３】
［第四実施形態］
図４は、本発明の電子写真感光体の第二実施形態を示す断面図である。図４に示す電子写真感光体１３０は、感光層６を単層構造とし、感光層６上に保護層５を備える以外は図２に示した電子写真感光体１１０と同様の構成を有する。
【０１３４】
［第五実施形態］
図５は、本発明の電子写真感光体の第五実施形態を示す断面図である。図５に示す電子写真感光体１４０は、感光層６と下引層４との間に中間層４２を備える以外は図１に示した電子写真感光体１００と同様の構成を有する。この中間層４２は、感光体１４０の電気特性の向上、画質の向上、感光層６の接着性向上のために設けられている。
【０１３５】
この中間層４２の構成材料は特に限定されず、合成樹脂、有機物質或いは無機物質の粉末、電子輸送性物質等から任意に選択することができる。
【０１３６】
中間層４２の合成樹脂としては、ポリビニルブチラールなどのアセタール樹脂、ポリビニルアルコール樹脂、カゼイン、ポリアミド樹脂、セルロース樹脂、ゼラチン、ポリウレタン樹脂、ポリエステル樹脂、メタクリル樹脂、アクリル樹脂、ポリ塩化ビニル樹脂、ポリビニルアセテート樹脂、塩化ビニル-酢酸ビニル-無水マレイン酸樹脂、シリコーン樹脂、シリコーン-アルキッド樹脂、フェノール-ホルムアルデヒド樹脂、メラミン樹脂等の高分子樹脂化合物、ジルコニウムキレート化合物、チタニウムキレート化合物、アルミニウムキレート化合物、チタニウムアルコキシド化合物、有機チタニウム化合物、シランカップリング剤等の公知の材料を用いることができる。
【０１３７】
そして、これらの化合物は単独にあるいは複数の化合物の混合物あるいは重縮合物として用いることができる。更にこれらの中でも、ジルコニウムキレート化合物、シランカップリング剤は残留電位が低く環境による電位変化が少なく、また繰り返し使用による電位の変化が少ないなど性能上優れている。
【０１３８】
上記のシランカップリング剤の例としてはビニルトリメトキシシラン、γ-メタクリルオキシプロピル-トリス(β-メトキシエトキシ)シラン、β-(3,4-エポキシシクロヘキシル)エチルトリメトキシシラン、γ-グリシドキシプロピルトリメトキシシラン、ビニルトリアセトキシシラン、γ-メルカプトプロピルトリメトキシシラン、γ-アミノプロピルトリエトキシシラン、N-β-(アミノエチル)-γ-アミノプロピルトリメトキシシラン、N-β-(アミノエチル)-γ-アミノプロピルメチルメトキシシラン、N,N-ビス(β-ヒドロキシエチル)-γ-アミノプロピルトリエトキシシラン、γ-クロルプロピルトリメトキシシランなどが挙げられる。
【０１３９】
これらの中でも特に好ましく用いられるシリコン化合物としては、ビニルトリエトキシシラン、ビニルトリス(2-メトキシエトキシシラン)、3-メタクリロキシプロピルトリメトキシシラン、3-グリシドキシプロピルトリメトキシシラン、2-(3,4-エポキシシクロヘキシル)エチルトリメトキシシラン、N-2-(アミノエチル)3-アミノプロピルトリメトキシシラン、N-2-(アミノエチル)3-アミノプロピルメチルジメトキシシラン、3-アミノプロピルトリエトキシシラン、N-フェニル-3-アミノプロピルトリメトキシシラン、3-メルカプトプロピルトリメトキシシラン、3-クロロプロピルトリメトキシシラン等のシランカップリング剤が挙げられる。
【０１４０】
ジルコニウムキレート化合物としては、ジルコニウムブトキシド、ジルコニウムアセト酢酸エチル、ジルコニウムトリエタノールアミン、アセチルアセトネートジルコニウムブトキシド、アセト酢酸エチルジルコニウムブトキシド、ジルコニウムアセテート、ジルコニウムオキサレート、ジルコニウムラクテート、ジルコニウムホスホネート、オクタン酸ジルコニウム、ナフテン酸ジルコニウム、ラウリン酸ジルコニウム、ステアリン酸ジルコニウム、イソステアリン酸ジルコニウム、メタクリレートジルコニウムブトキシド、ステアレートジルコニウムブトキシド、イソステアレートジルコニウムブトキシド等が挙げられる。
【０１４１】
チタニウムキレート化合物としては、テトライソプロピルチタネート、テトラノルマルブチルチタネート、ブチルチタネートダイマー、テトラ(2-エチルヘキシル)チタネート、チタンアセチルアセトネート、ポリチタンアセチルアセトネート、チタンオクチレングリコレート、チタンラクテートアンモニウム塩、チタンラクテート、チタンラクテートエチルエステル、チタントリエタノールアミネート、ポリヒドロキシチタンステアレート等が挙げられる。
【０１４２】
アルミニウムキレート化合物としては、アルミニウムイソプロピレート、モノブトキシアルミニウムジイソプロピレート、アルミニウムブチレート、ジエチルアセトアセテートアルミニウムジイソプロピレート、アルミニウムトリス(エチルアセトアセテート)等が挙げられる。
【０１４３】
中間層４２中には、電気特性の向上や光散乱性の向上などの目的により、各種の有機化合物の微粉末もしくは無機化合物の微粉末を添加することができる。特に、酸化チタン、酸化亜鉛、亜鉛華、硫化亜鉛、鉛白、リトポン等の白色顔料やアルミナ、炭酸カルシウム、硫酸バリウム等の体質顔料としての無機顔料やテフロン樹脂粒子、ベンゾグアナミン樹脂粒子、スチレン樹脂粒子などが有効である。
【０１４４】
添加微粉末の粒径は０．０１〜２μｍのものが用いられる。微粉末は必要に応じて添加されるが、その添加量は中間層４２の固形分の総質量に対して、質量比で１０〜９０質量％であることが好ましく、３０〜８０質量％であることがより好ましい。
【０１４５】
また、中間層４２中には、先に説明した電子輸送性物質、電子輸送性顔料等を含有させることも低残留電位化や環境安定性の観点から有効である。更に、中間層４２の厚みは０．０１〜３０μｍであることが好ましく、０．０５〜２５μｍであることがより好ましい。
【０１４６】
また、中間層４２を形成するための塗布液の調製する際に、微粉末状の物質を添加する場合には樹脂成分を溶解した溶液中に添加して分散処理が行われる。この分散処理方法としては、ロールミル、ボールミル、振動ボールミル、アトライター、サンドミル、コロイドミル、ペイントシェーカーなどの方法を用いることができる。
【０１４７】
更に、この中間層４２は導電性支持体層３上に中間層４２を形成するための塗布液を塗布し、乾燥させることにより形成することができる。このときの塗布方法としては、ブレードコーティング法、ワイヤーバーコーティング法、スプレーコーティング法、浸漬コーティング法、ビードコーティング法、エアーナイフコーティング法、カーテンコーティング法等の通常の方法を用いることができる。
【０１４８】
［第六実施形態］
図６は、本発明の電子写真感光体の第六実施形態を示す断面図である。図６に示す電子写真感光体１５０は、感光層６を単層構造とし、感光層６と下引層４との間に中間層４２を備える以外は図１に示した電子写真感光体１００と同様の構成を有する。
【０１４９】
そして、中間層４２は、上述の図５に示した感光体１４０と同様の構成を有する。
【０１５０】
［第七実施形態］
図７は、本発明の電子写真感光体の第七実施形態を示す断面図である。
【０１５１】
図７に示す電子写真感光体１６０は、感光層６上に保護層５を設け、感光層６と下引層４との間に中間層４２を備える以外は図１に示した電子写真感光体１００と同様の構成を有する。
【０１５２】
そして、中間層４２は、上述の図５に示した感光体１４０の中間層４２と同様の構成を有する。また、保護層５も上述の図３に示した感光体１２０の保護層５と同様の構成を有する。
【０１５３】
［第八実施形態］
図８は、本発明の電子写真感光体の第七実施形態を示す断面図である。
【０１５４】
図８に示す電子写真感光体１７０は、感光層６上に保護層５を設け、感光層６を単層構造とし、感光層６と下引層４との間に中間層４２を備える以外は図１に示した電子写真感光体１００と同様の構成を有する。
【０１５５】
そして、中間層４２は、上述の図５に示した感光体１４０の中間層４２と同様の構成を有する。また、保護層５も上述の図３に示した感光体１２０の保護層５と同様の構成を有する。更に、感光層６も上述の図２（ｂ）に示した感光体１１０の感光層６と同様の構成を有する。
【０１５６】
以上、本発明の電子写真感光体の好適な実施形態について詳細に説明したが、本発明の電子写真感光体は上記実施形態に限定されるものではない。
【０１５７】
例えば、本発明の電子写真感光体の感光層には、図１、図３及び図５に示した感光体１００、１２０及び１３０のように２層からなる構成の場合、図２、図２（ｂ）及び図６に示した感光体１１０、１３０及び１５０のように単層構造の場合の何れにおいても、電子写真装置中で発生するオゾンや酸化性ガス、あるいは光・熱による感光体の劣化を防止する目的で、酸化防止剤・光安定剤・熱安定剤などの添加剤を添加してもよい。
【０１５８】
例えば、酸化防止剤としてはヒンダードフェノール、ヒンダードアミン、パラフェニレンジアミン、アリールアルカン、ハイドロキノン、スピロクロマン、スピロインダノン及びそれらの誘導体、有機硫黄化合物、有機燐化合物などが挙げられる。
【０１５９】
酸化防止剤の具体的な化合物例として、フェノール系酸化防止剤では2,6-ジ-t-ブチル-4-メチル フェノール、スチレン化フェノール、n-オクタデシル-3-(3',5'-ジ-t-ブチル 4'-ヒドロキシフェニル)-プロピオネート、2,2'-メチレン-ビス-(4-メチル-6-t-ブチル フェノール)、2-t-ブチル-6-(3'-t-ブチル-5'-メチル-2'-ヒドロキシベンジル)-4-メチルフェニル アクリレート、4,4'-ブチリデン-ビス-(3-メチル-6-t-ブチル-フェノール)、4,4'-チオ-ビス-(3-メチル 6-t-ブチルフェノール)、1,3,5-トリス(4-t-ブチル-3-ヒドロキシ-2,6-ジメチル ベンジル)イソシアヌレート、テトラキス-[メチレン-3-(3',5'-ジ-t-ブチル-4'-ヒドロキシ-フェニル)プロピオネート]-メタン、3,9-ビス[2-[3-(3-t-ブチル-4-ヒドロキシ-5-メチル フェニル)プロピオニルオキシ]-1,1-ジメチル エチル]-2,4,8,10-テトラオキサスピロ[5,5]ウンデカンなどが挙げられる。
【０１６０】
ヒンダードアミン系化合物としては、ビス(2,2,6,6-テトラメチル-4-ピペリジル)セバケート、ビス(1,2,2,6,6-ペンタメチル-4-ピペリジル)セバケート、1-[2-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオニルオキシ]エチル]-4-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオニルオキシ]-2,2,6,6-テトラメチルピペリジン、8-ベンジル-7,7,9,9-テトラメチル-3-オクチル-1,3,8-トリアザスピロ[4,5]ウンデカン-2,4-ジオン、4-ベンゾイルオキシ-2,2,6,6-テトラメチルピペリジン、コハク酸ジメチル-1-(2-ヒドロキシエチル)-4-ヒドロキシ-2,2,6,6-テトラメチルピペリジン重縮合物、ポリ[[6-(1,1,3,3-テトラメチルブチル)イミノ-1,3,5-トリアジン-2,4-ジイミル][(2,2,6,6-テトラメチル-4-ピペリジル)イミノ]ヘキサメチレン[(2,3,6,6-テトラメチル-4-ピペリジル)イミノ]]、2-(3,5-ジ-t-ブチル-4-ヒドロキシベンジル)-2-n-ブチルマロン酸ビス(1,2,2,6,6-ペンタメチル-4-ピペリジル)、N,N'-ビス(3-アミノプロピル)エチレンジアミン-2,4-ビス[N-ブチル-N-(1,2,2,6,6,-ペンタメチル-4ピペリジル)アミノ]-6-クロロ-1,3,5-トリアジン縮合物などが挙げられる。
【０１６１】
有機イオウ系酸化防止剤としては、ジラウリル-3,3'-チオジプロピオネート、ジミリスチル-3,3'-チオジプロピオネート、ジステアリル-3,3'-チオジプロピオネート、ペンタエリスリトール-テトラキス-(β-ラウリル-チオプロピオネート)、ジトリデシル-3,3'-チオジプロピオネート、2-メルカプト ベンズイミダゾールなどが挙げられる。有機燐系酸化防止剤としてトリスノニルフェニル フォスフィート、トリフェニル フォスフィート、トリス(2,4-ジ-t-ブチル フェニル)-フォスフィートなどが挙げられる。
【０１６２】
有機硫黄系および有機燐系酸化防止剤は2次酸化防止剤と言われフェノール系あるいはアミン系などの1次酸化防止剤と併用することにより相乗効果を得ることができる。
【０１６３】
光安定剤としては、ベンゾフェノン系、ベンゾトリアゾール系、ジチオカルバメート系、テトラメチルピペリジン系などの誘導体が挙げられる。例えば、ベンゾフェノン系光安定剤としては、2-ヒドロキシ-4-メトキシ ベンゾフェノン、2-ヒドロキシ-4-オクトキシ ベンゾフェノン、2,2'-ジ-ヒドロキシ-4-メトキシ ベンゾフェノンなどが挙げられる。
【０１６４】
ベンゾトリアゾール系系光安定剤としては、2-(-2'-ヒドロキシ-5'メチル フェニル-)-ベンゾトリアゾール、2-[2'-ヒドロキシ-3'-(3'',4'',5'',6''-テトラ-ヒドロフタルイミド-メチル)-5'-メチルフェニル]-ベンゾトリアゾール、2-(-2'-ヒドロキシ-3'-t-ブチル 5'-メチルフェニル-)-5-クロロ ベンゾトリアゾール、2-(2'-ヒドロキシ-3'-t-ブチル 5'-メチルフェニル-)-5-クロロ ベンゾトリアゾール、2-(2'-ヒドロキシ-3',5'-t-ブチルフェニル-)-ベンゾトリアゾール、2-(2'-ヒドロキシ-5'-t-オクチル フェニル)-ベンゾトリアゾール、2-(2'-ヒドロキシ 3',5'-ジ-t-アミル フェニル-)-ベンゾトリアゾールなどが挙げられる。
【０１６５】
その他の化合物としては、2,4,ジ-t-ブチルフェニル 3',5'-ジ-t-ブチル-4'-ヒドロキシベンゾエート、ニッケル ジブチル-ジチオカルバメートなどがある。
【０１６６】
また、感光層６には、感度の向上、残留電位の低減、繰り返し使用時の疲労低減等を目的として少なくとも1種の電子受容性物質を含有させることができる。
【０１６７】
使用可能な電子受容性物質としては、例えば無水琥珀酸、無水マレイン酸、ジブロム無水マレイン酸、無水フタル酸、テトラブロム無水フタル酸、テトラシアノエチレン、テトラシアノキノジメタン、o-ジニトロベンゼン、ｍ−ジニトロベンゼン、クロラニル、ジニトロアントラキノン、トリニトロフルオレノン、ピクリン酸、o-ニトロ安息香酸、p-ニトロ安息香酸、フタル酸などが挙げられる。
【０１６８】
これらのうち、フルオレノン系、キノン系や、−Cl,−CN,−NO₂等の電子吸引性置換基を有するベンゼン誘導体が特に好ましく用いられる。更に、本発明の感光層形成用塗布液には、塗膜の平滑性向上のためのレベリング剤としてシリコーンオイルを微量添加することもできる。
【０１６９】
以上説明した本発明の本発明の電子写真感光体は、近赤外光もしくは可視光に発光するレーザービームプリンター、デイジタル複写機、LEDプリンター、レーザーファクシミリなどの電子写真装置や、このような電子写真装置に備えれられるプロセスカートリッジに搭載することができる。また、本発明の電子写真感光体は一成分系、二成分系の正規現像剤あるいは反転現像剤とも合わせて用いることができる。また本発明の電子写真感光体は帯電ローラーや帯電ブラシを用いた接触帯電方式の電子写真装置に搭載されても電流リークの発生が少ない良好な特性が得られる。
【０１７０】
次に、本発明の本発明の電子写真感光体を搭載した電子写真装置及びプロセスカートリッジについて説明する。
【０１７１】
図９は、本発明の電子写真装置の好適な一実施形態の基本構成を概略的に示す断面図である。図９に示す電子写真装置２００は、電子写真感光体７と、電子写真感光体７をコロナ放電方式により帯電させるコロトロンやスコロトロンなどの帯電手段８と、帯電手段８に接続された電源９と、帯電手段８により帯電される電子写真感光体７を露光して静電潜像を形成する露光手段１０と、露光手段１０により形成された静電潜像をトナーにより現像してトナー像を形成する現像手段１１と、現像手段１１により形成されたトナー像を被転写媒体に転写する転写手段１２と、クリーニング装置１３と、除電器１４と、定着装置１５とを備える。
【０１７２】
また、図１０は、図９に示す本発明の電子写真装置の別の実施形態の基本構成を概略的に示す断面図である。
【０１７３】
図１０に示す電子写真装置２１０は、電子写真感光体７を接触方式により帯電させる帯電手段８を備えていること以外は、図９に示した電子写真装置２００と同様の構成を有する。特に、直流電圧に交流電圧を重畳した接触式の帯電手段を採用する電子写真装置においては、優れた耐摩耗性を有するため、好ましく使用できる。なお、この場合には、除電器１４が設けられていないものもある。
【０１７４】
帯電手段（帯電用部材）８は、感光体７の表面に接触するように配置され、感光体に電圧を均一に印加し、感光体表面を所定の電位に帯電させるものである。帯電手段８にはアルミニウム、鉄、銅などの金属、ポリアセチレン、ポリピロール、ポリチオフェンなどの導電性高分子材料、ポリウレタンゴム、シリコーンゴム、エピクロロヒドリンゴム、エチレンプロピレンゴム、アクリルゴム、フッソゴム、スチレンーブタジエンゴム、ブタジエンゴム等のエラストマー材料にカーボンブラック、沃化銅、沃化銀、硫化亜鉛、炭化けい素、金属酸化物などの金属酸化物粒子を分散したものなどを用いることができる。
【０１７５】
この金属酸化物の例としてはZｎO、SnO₂、TiO₂、In₂O₃、MoO₃等、あるいはこれらの複合酸化物が挙げられる。また、帯電手段８にはエラストマー材料中に過塩素酸塩を含有させて導電性を付与したものを使用しても良い。
【０１７６】
更に、帯電手段８にはその表面に被覆層を設けてもよい。被覆層を形成する材料としては、N-アルコキシメチル化ナイロン、セルロース樹脂、ビニルピリジン樹脂、フェノール樹脂、ポリウレタン、ポリビニルブチラール、メラミン等が単独、あるいは併用して用いられる。また、エマルジョン樹脂系材料、たとえば、アクリル樹脂エマルジョン、ポリエステル樹脂エマルジョン、ポリウレタン、特にソープフリーのエマルジョン重合により合成されたエマルジョン樹脂を用いることも出来る。
【０１７７】
これらの樹脂にはさらに抵抗率を調整するために、導電剤粒子を分散してもよいし、劣化を防止するために酸化防止剤を含有させることもできる。また、被覆層を形成する時の成膜性を向上させるために、エマルジョン樹脂にレベリング剤または界面活性剤を含有させることもできる。また、この接触帯電用部材の形状としては、ローラー型、ブレード型、ベルト型、ブラシ型、などが挙げられる。
【０１７８】
さらに、帯電手段８の電気抵抗値は、好ましくは10²〜10¹⁴Ωcm、さらに好ましくは10²〜10¹²Ωcmの範囲が良い。また、この接触帯電用部材への印加電圧は、直流、交流いずれも用いることができる。又、直流＋交流の形で印加することもできる。
【０１７９】
図１１は図９に示す本発明の電子写真装置の更に別の実施形態の基本構成を概略的に示す断面図である。図１１に示す電子写真装置２２０は中間転写方式の電子写真装置であり、ハウジング４００内において４つの電子写真感光体４０１ａ〜４０１ｄが中間転写ベルト４０９に沿って相互に並列に配置されている。
【０１８０】
ここで、電子写真装置２２０に搭載されている電子写真感光体４０１ａ〜４０１ｄは、それぞれ本発明の電子写真感光体である。例えば、先に述べた電子写真感光体１００、電子写真感光体１１０、電子写真感光体１２０、電子写真感光体１３０、電子写真感光体１４０、電子写真感光体１５０、電子写真感光体１６０、電子写真感光体１７０のいずれかが搭載されていてもよい。
【０１８１】
電子写真感光体１ａ〜４０１ｄのそれぞれは所定の方向（紙面上は反時計回り）に回転可能であり、その回転方向に沿って帯電ロール４０２ａ〜４０２ｄ、現像装置４０４ａ〜４０４ｄ、１次転写ロール４１０ａ〜４１０ｄ、クリーニングブレード１５ａ〜１５ｄが配置されている。現像装置４０４ａ〜４０４ｄのそれぞれにはトナーカートリッジ４０５ａ〜４０５ｄに収容されたブラック、イエロー、マゼンタ、シアンの４色のトナーが供給可能であり、また、１次転写ロール４１０ａ〜４１０ｄはそれぞれ中間転写体９を介して電子写真感光体１ａ〜４０１ｄに当接している。
【０１８２】
更に、ハウジング４００内の所定の位置にはレーザ光源（露光手段）４０３が配置されており、レーザ光源４０３から出射されたレーザー光を帯電後の電子写真感光体１ａ〜４０１ｄの表面に照射することが可能となっている。これにより、電子写真感光体１ａ〜４０１ｄの回転工程において帯電、露光、現像、１次転写、クリーニングの各工程が順次行われ、各色のトナー像が中間転写ベルト４０９上に重ねて転写される。
【０１８３】
中間転写ベルト４０９は駆動ロール４０６、バックアップロール４０８及びテンションロール４０７により所定の張力をもって支持されており、これらのロールの回転によりたわみを生じることなく回転可能となっている。また、２次転写ロール４１３は、中間転写体９を介してバックアップロール４０８と当接するように配置されている。バックアップロール４０８と２次転写ロール４１３との間を通った中間転写ベルト４０９はクリーニングブレード１４により清浄面化された後、次の画像形成プロセスに繰り返し供される。
【０１８４】
また、ハウジング４００内の所定の位置にはトレイ（被転写媒体トレイ）４１１が設けられており、トレイ４１１内の紙などの被転写媒体が移送ロール４１２により中間転写ベルト４０９と２次転写ロール４１３との間、さらには相互に当接する２個の定着ロール４１４の間に順次移送された後、ハウジング４００の外部に排紙される。
【０１８５】
更に、図１２は、本発明のプロセスカートリッジの好適な一実施形態の基本構成を概略的に示す断面図である。プロセスカートリッジ３００は、電子写真感光体７とともに、帯電手段８、現像手段１１、クリーニング装置（クリーニング手段）１３、露光のための開口部１８、及び除電器１４を取り付けレール１６を用いて組み合せ、そして一体化したものである。
【０１８６】
そして、このプロセスカートリッジ３００は、転写手段１２と、定着装置１５と、図示しない他の構成部分とからなる電子写真装置本体に対して着脱自在としたものであり、電子写真装置本体とともに電子写真装置を構成するものである。
【０１８７】
【実施例】
以下、実施例及び比較例を挙げて本発明の内容をさらに詳しく説明するが、本発明はこれらの実施例に何ら限定されるものではない。
【０１８８】
以下に示す手順により図１に示した電子写真感光体１００と同様の構成を有する実施例１〜実施例４、比較例１〜比較例６の電子写真感光体を作製した。
【０１８９】
なお、各電子写真感光体の下引層を作製する際、金属酸化物粒子Ａの蛍光Ｘ線分析は蛍光Ｘ線分析装置（商品名：システム３３７０Ｅ，理学電気社製）を用いて以下の条件で行った。すなわち、Ｘ線源のターゲット：Ｒｈ，Ｘ線源への印加電圧：５０ｋＶ，電流値：５０ｍＡとし、光学系の分光結晶には、測定対象となる金属酸化物粒子Ａ中の検出元素の種類に応じてＬｉＦ，ＴＡＰ，ＰＥＴ，Ｇｅを使用した。また、検出器はシンチレーションカウンターとフォトカウンターを用いた。更に、分光器の走査はスキップスキャン法を用い、１ステップあたり０．０５度の角度に設定して特性Ｘ線強度の測定を行った。
【０１９０】
また、金属酸化物粒子Ｂ或いは金属酸化物粒子Ａの比表面積の測定は、流動式比表面積自動測定装置フローソーブII２３００型（島津製作所社製）を用い、測定対象となる金属酸化物粒子２００ｍｇを２００℃、３０分脱ガス処理を行った後、ＢＥＴ１点法にて比表面積値を測定した。
【０１９１】
（実施例１）
以下の手順にて図１に示した電子写真感光体１００と同様の構成を有する感光体を作製した。
【０１９２】
酸化スズ（商品名：Ｓ１，三菱マテリアル製，比表面積：５０ｍ²／ｇ）：１００質量部をトルエン５００質量部と攪拌混合し、シランカップリング剤（商品名：Ａ１１００，日本ユニカー社製）：１５質量部を添加し、５時間攪拌した。その後、トルエンを減圧蒸留にて留去し、１００℃で２時間焼き付けを行った。
【０１９３】
得られた表面処理後の酸化スズに対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｓｎの特性Ｘ線強度Ｉ２」は２．０×１０^-4であった。また、表面処理後の酸化スズの比表面積は６０ｍ²／ｇであった。
【０１９４】
次に、表面処理後の酸化スズ：３５質量部と、硬化剤（ブロック化イソシアネート スミジュール3175，住友バイエルンウレタン社製） ：１５質量部と、ブチラール樹脂 BM-1 (積水化学社製)：６質量部と、メチルエチルケトン：４４質量部とを混合し、1mmφのガラスビーズを用いてサンドミルにて２時間の分散を行い分散液を得た。
【０１９５】
得られた分散液に触媒としてジオクチルスズジラウレート：０．００５質量部と、シリコーンオイルＳＨ２９ＰＡ（東レダウコーニングシリコーン社製）：０．０１質量部とを添加し、下引層用塗布液を得た。この塗布液を浸漬塗布法にて直径３０ｍｍ、長さ３４０ｍｍ、厚さ１ｍｍのアルミニウム基材（導電性支持体層）上に塗布し、１６０℃、１００分の乾燥硬化を行い厚さ２０μｍの下引層を形成した。
【０１９６】
次に、下引層上に２層構造の感光層を形成した。まず、電荷発生物質としてのCukα線を用いたＸ線回折スペクトルのブラッグ角度(２θ±０．２°)が少なくとも７．４゜，１６．６゜，２５．５゜，２８．３゜の位置に回折ピークを有する塩化ガリウムフタロシアニン：１５質量部、バインダー樹脂となる塩化ビニル・酢酸ビニル共重合体樹脂（ＶＭＣＨ、日本ユニカー社製）１０質量部、ｎ-ブチルアセテート：３００質量部からなる混合物を、1mmφのガラスビーズを用いてサンドミルにて４時間分散した。
【０１９７】
得られた分散液を電荷発生層形成用の塗布液として下引層上に浸漬塗布し、乾燥して、層厚が０．２μｍの電荷発生層を形成した。
【０１９８】
さらに、N,N'-ジフェニル-N,N'-ビス(3-メチルフェニル)-[1、1']ビフェニル-4,4'-ジアミン：４質量部と、ビスフェノールＺポリカーボネート樹脂（粘度平均分子量４万）：６質量部とをクロロベンゼン：８０質量部に加えて溶解した。得られた分散液を電荷輸送層形成用の塗布液として電荷発生層上に浸漬塗布し、１３０℃、４０分の乾燥を行うことにより層厚が２５μmの電荷輸送層を形成した。
【０１９９】
（実施例２）
以下の手順にて図１に示した電子写真感光体１００と同様の構成を有する感光体を作製した。
【０２００】
酸化チタン（商品名：TAF５００J，富士チタン社製，比表面積：１８ｍ²／ｇ）：１００質量部をミキサ中で攪拌しながら、これにトルエン１０質量部とシランカップリング剤（商品名：KBM503，信越化学社製）：２質量部との混合液を添加し、１０分間攪拌した。その後、トルエンを減圧蒸留にて留去し、１７０℃で２時間焼き付けを行った。
【０２０１】
得られた表面処理後の酸化チタンに対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｔｉの特性Ｘ線強度Ｉ２」は２．０×１０^-4であった。また、表面処理後の酸化スズの比表面積は２０ｍ²／ｇであった。
【０２０２】
次に、表面処理後の酸化チタン：５０質量部と、硬化剤（ブロック化イソシアネート スミジュール3175，住友バイエルンウレタン社製） ：１５質量部と、ブチラール樹脂 BM-1 (積水化学社製)：６質量部と、メチルエチルケトン：６０質量部とを混合し、1mmφのガラスビーズを用いてサンドミルにて４時間の分散を行い分散液を得た。
【０２０３】
得られた分散液に触媒としてジオクチルスズジラウレート：０．００５質量部と、シリコーンオイルＳＨ２９ＰＡ（東レダウコーニングシリコーン社製）：０．０１質量部とを添加し、下引層用塗布液を得た。この塗布液を浸漬塗布法にて直径３０ｍｍ、長さ３４０ｍｍ、厚さ１ｍｍのアルミニウム基材（導電性支持体層）上に塗布し、１６０℃、１００分の乾燥硬化を行い厚さ２０μｍの下引層を形成した。
【０２０４】
次に、実施例１と同様の手順で電荷発生層と電荷輸送層とを順次形成し、電子写真感光体を作製した。
【０２０５】
（実施例３）
以下の手順にて図１に示した電子写真感光体１００と同様の構成を有する感光体を作製した。
【０２０６】
酸化亜鉛（平均粒子径７０ｎｍ，テイカ社製試作品，比表面積：１５ｍ²／ｇ）：１００質量部をトルエン５００質量部と撹拌混合し、これにシランカップリング剤（商品名：KBM６０３，信越化学社製）：１．５質量部を添加し、２時間攪拌した。その後、トルエンを減圧蒸留にて留去し、１５０℃で２時間焼き付けを行った。
【０２０７】
得られた表面処理後の酸化亜鉛に対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｚｎの特性Ｘ線強度Ｉ２」は１．５×１０^-5であった。また、表面処理後の酸化スズの比表面積は１５ｍ²／ｇであった。
【０２０８】
次に、表面処理後の酸化亜鉛：６０質量部と、硬化剤（ブロック化イソシアネート スミジュール3175，住友バイエルンウレタン社製） ：１５質量部と、ブチラール樹脂 BM-1 (積水化学社製)：１５質量部と、メチルエチルケトン：８５質量部とを混合した。得られた液：８質量部とメチルエチルケトン：２５質量部とを混合し、1mmφのガラスビーズを用いてサンドミルにて２時間の分散を行い分散液を得た。
【０２０９】
得られた分散液に触媒としてジオクチルスズジラウレート：０．００５質量部と、シリコーンオイルＳＨ２９ＰＡ（東レダウコーニングシリコーン社製）：０．０１質量部とを添加し、下引層用塗布液を得た。この塗布液を浸漬塗布法にて直径３０ｍｍ、長さ３４０ｍｍ、厚さ１ｍｍのアルミニウム基材（導電性支持体層）上に塗布し、１６０℃、１００分の乾燥硬化を行い厚さ２０μｍの下引層を形成した。
【０２１０】
次に、下引層上に２層構造の感光層を形成した。まず、電荷発生物質としてのCukα線を用いたＸ線回折スペクトルのブラッグ角度(２θ±０．２°)が少なくとも７．３゜，１６．０゜，２４．９゜，２８．０゜の位置に回折ピークを有するヒドロキシガリウムフタロシアニン：１５質量部、バインダー樹脂となる塩化ビニル・酢酸ビニル共重合体樹脂（ＶＭＣＨ、日本ユニカー社製）１０質量部、ｎ-ブチルアセテート：３００質量部からなる混合物を、1mmφのガラスビーズを用いてサンドミルにて４時間分散した。
【０２１１】
得られた分散液を電荷発生層形成用の塗布液として下引層上に浸漬塗布し、乾燥して、層厚が０．２μｍの電荷発生層を形成した。次に、実施例１と同様の手順で電荷輸送層を形成し、電子写真感光体を作製した。
【０２１２】
（実施例４）
以下の手順にて図１に示した電子写真感光体１００と同様の構成を有する感光体を作製した。
【０２１３】
酸化亜鉛（商品名：ＭＺ３００，テイカ社製，比表面積：４０ｍ²／ｇ）：１００質量部をトルエン５００質量部と攪拌混合し、これにシランカップリング剤（商品名：KBM４０３，信越化学社製）：５質量部を添加し、２時間攪拌した。その後、トルエンを減圧蒸留にて留去し、１５０℃で２時間焼き付けを行った。
【０２１４】
得られた表面処理後の酸化亜鉛に対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｚｎの特性Ｘ線強度Ｉ２」は５．０×１０^-5であった。また、表面処理後の酸化スズの比表面積は３０ｍ²／ｇであった。
【０２１５】
次に、表面処理後の酸化亜鉛：６０質量部と、硬化剤（ブロック化イソシアネート スミジュール3175，住友バイエルンウレタン社製） ：１５質量部と、ブチラール樹脂 BM-1 (積水化学社製)：１５質量部と、メチルエチルケトン：８５質量部とを混合した。得られた液：３８質量部とメチルエチルケトン：２５質量部とを混合し、1mmφのガラスビーズを用いてサンドミルにて２時間の分散を行い分散液を得た。
【０２１６】
得られた分散液に触媒としてジオクチルスズジラウレート：０．００５質量部と、シリコーンオイルＳＨ２９ＰＡ（東レダウコーニングシリコーン社製）：０．０１質量部とを添加し、下引層用塗布液を得た。この塗布液を浸漬塗布法にて直径３０ｍｍ、長さ３４０ｍｍ、厚さ１ｍｍのアルミニウム基材（導電性支持体層）上に塗布し、１６０℃、１００分の乾燥硬化を行い厚さ２０μｍの下引層を形成した。
【０２１７】
次に、下引層上に２層構造の感光層を形成した。まず、電荷発生物質としてのCukα線を用いたＸ線回折スペクトルのブラッグ角度(２θ±０．２°)が少なくとも２７．３゜の位置に回折ピークを有するオキシチタニルフタロシアニン：１５質量部、バインダー樹脂となる塩化ビニル・酢酸ビニル共重合体樹脂（ＶＭＣＨ、日本ユニカー社製）１０質量部、ｎ-ブチルアセテート：３００質量部からなる混合物を、1mmφのガラスビーズを用いてサンドミルにて４時間分散した。
【０２１８】
得られた分散液を電荷発生層形成用の塗布液として下引層上に浸漬塗布し、乾燥して、層厚が０．２μｍの電荷発生層を形成した。次に、実施例１と同様の手順で電荷輸送層を形成し、電子写真感光体を作製した。
【０２１９】
（比較例１）
実施例１で用いた金属酸化物微粒子を表面処理しないで使用したこと以外は、実施例１と同様にして電子写真感光体を作製した。
【０２２０】
（比較例２）
実施例２で用いた金属酸化物微粒子を表面処理しないで使用したこと以外は、実施例２と同様にして電子写真感光体を作製した。
【０２２１】
（比較例３）
実施例３で用いた金属酸化物微粒子を表面処理しないで使用したこと以外は、実施例３と同様にして電子写真感光体を作製した。
【０２２２】
（比較例４）
実施例４で用いた金属酸化物微粒子を表面処理しないで使用したこと以外は、実施例４と同様にして電子写真感光体を作製した。
【０２２３】
（比較例５）
実施例３で用いたシランカップリング剤（商品名：KBM503，信越化学社製）の添加量を３０質量部にかえたこと以外は、実施例３と同様にして電子写真感光体を作製した。
【０２２４】
得られた表面処理後の酸化亜鉛に対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｚｎの特性Ｘ線強度Ｉ２」は２．０×１０^-3であった。また、表面処理後の酸化スズの比表面積は１５ｍ²／ｇであった。
【０２２５】
（比較例６）
実施例４で用いたシランカップリング剤（商品名：KBM503，信越化学社製）の添加量を０．０５質量部にかえたこと以外は、実施例４と同様にして電子写真感光体を作製した。
【０２２６】
得られた表面処理後の酸化亜鉛に対して上述の蛍光Ｘ線分析をおこなった結果、「Ｓｉの特性Ｘ線強度Ｉ１／Ｚｎの特性Ｘ線強度Ｉ２」は５．０×１０^-8であった。また、表面処理後の酸化スズの比表面積は３０ｍ²／ｇであった。
【０２２７】
［電子写真感光体の電子写真特性評価試験］
（１）使用初期の特性評価（初期電位測定）
実施例１〜実施例４及び比較例１〜比較例６の電子写真感光体を図９と同様の構造を有するレーザープリンタ−スキャナー（商品名：XP-15の改造機、富士ゼロックス社製）に搭載し、それぞれの電子写真感光体の電子写真特性を以下のように評価した。
【０２２８】
常温常湿（２０℃、４０％ＲＨ）環境下、グリッド印加電圧−７００Ｖのスコロトロン帯電器で各電子写真感光体を帯電させたときの各電子写真感光体の表面の電位Ａ［Ｖ］を測定した。次に、７８０ｎｍの半導体レーザーを用いて、帯電させてから1秒後の各電子写真感光体に１０ｍＪ/ｍ²の光を照射して放電を行わせ、このときの各電子写真感光体の表面の電位Ｂ［Ｖ］を測定した。続いて、放電させてから３秒後各電子写真感光体に５０ｍＪ/ｍ²の赤色ＬＥＤ光を照射して除電を行い、このときの各電子写真感光体の表面の電位Ｃ［Ｖ］を測定した。
【０２２９】
ここで、電位Ａの値が高いほど、電子写真感光体の受容電位が高いので、コントラストを高く取ることができることになる。また、電位Ｂの値が低いほど高感度な電子写真感光体であることになる。更に、電位Ｃの値が低いほど残留電位が少なく、画像メモリーやいわゆるかぶりが少ない電子写真感光体と評価される。これらの結果を表１に示す。
【０２３０】
（２）繰り返し使用後の特性評価
上記の操作を1万回繰り返し、帯電、露光後の電位Ａ〜電位Ｃの測定を行った。これらの結果を表１に示す。
【０２３１】
（３）使用環境の変化に対する安定性評価
上記の操作を低温低湿（10℃、15％ＲＨ）、高温高湿（28℃、85%ＲＨ）の２つの異なる環境下で行い、帯電、露光後の電位Ａ〜電位Ｃの測定を行った。そして、これらの異なる環境間での電位Ａ〜電位Ｃの値の変動量（ΔＡ、ΔＢ、ΔＣ）を測定し、使用環境の変化に対する各電子写真感光体の安定性評価を行った。これらの結果を表１に示す。
【０２３２】
（４）１万枚プリント後の画質評価
実施例１〜実施例４及び比較例１〜比較例６の電子写真感光体を図１１と同様の構造を有する接触帯電装置、中間転写装置を有するフルカラープリンター（商品名：Docu Print C620、富士ゼロックス社製）に搭載し、１万枚の紙への連続プリントテストを行った。
【０２３３】
そして、１万枚プリント後の画質を、「異常なし」；良好な画質が得られた、「全面かぶり発生」；紙面全体に微細な黒点がみられる、「黒点発生」；紙面に大きな黒点がみられる、とした評価基準のもとで評価した。これらの結果を表１に示す。
【０２３４】
【表１】

【０２３５】
【発明の効果】
以上説明したように、本発明の電子写真感光体の製造方法によれば、繰り返し使用に伴う電気特性の低下を十分に防止することのできる高い耐久性と高い解像品質を得ることができる電子写真感光体を提供することができる。そして、このような電子写真感光体を備えることにより、長期にわたり繰り返し使用しても高い解像品質を得ることのできるプロセスカートリッジ並びに電子写真装置を提供することできる。
【図面の簡単な説明】
【図１】本発明の電子写真感光体の第一実施形態を示す断面図である。
【図２】本発明の電子写真感光体の第二実施形態を示す断面図である。
【図３】本発明の電子写真感光体の第三実施形態を示す断面図である。
【図４】本発明の電子写真感光体の第四実施形態を示す断面図である。
【図５】本発明の電子写真感光体の第五実施形態を示す断面図である。
【図６】本発明の電子写真感光体の第六実施形態を示す断面図である。
【図７】本発明の電子写真感光体の第七実施形態を示す断面図である。
【図８】本発明の電子写真感光体の第八実施形態を示す断面図である。
【図９】本発明の電子写真装置の好適な一実施形態の基本構成を概略的に示す断面図である。
【図１０】図９に示す本発明の電子写真装置の別の実施形態の基本構成を概略的に示す断面図である。
【図１１】図９に示す本発明の電子写真装置の更に別の実施形態の基本構成を概略的に示す断面図である。
【図１２】本発明のプロセスカートリッジの好適な一実施形態の基本構成を概略的に示す断面図である。
【符号の説明】
１…電荷発生層、３…導電性支持体層、４…下引層、５…保護層、６…感光層、７…電子写真感光体、８…帯電手段、９…電源、１０…露光手段、１１…現像手段、１２…転写手段、１３…クリーニング装置、１４…除電器、１６…取り付けレール、１８…露光のための開口部、４２…中間層、１００，１１０，１２０，１３０，１４０，１５０，１６０，１７０…電子写真感光体、２００…電子写真装置、２１０…電子写真装置、３００…プロセスカートリッジ、４００・・・ハウジング、４０１ａ〜４０１ｄ・・・電子写真感光体、４０２ａ〜４０２ｄ・・・帯電ロール、４０３・・・レーザ光源（露光装置）、４０４ａ〜４０４ｄ・・・現像装置、４０５ａ〜４０５ｄ・・・トナーカートリッジ、４０６・・・駆動ロール、４０７・・・テンションロール、４０８・・・バックアップロール、４０９・・・中間転写ベルト、４１０ａ〜４１０ｄ・・・１次転写ロール、４１１・・・トレイ（被転写体トレイ）、４１２・・・移送ロール、４１３・・・２次転写ロール、４１４・・・定着ロール。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an electrophotographic photoreceptor, an electrophotographic photoreceptor, a process cartridge, and an electrophotographic apparatus.
[0002]
[Prior art]
In recent years, an electrophotographic photosensitive member has an advantage that high-speed and high printing quality can be obtained, and is therefore widely used in fields such as copying machines and laser beam printers. As an electrophotographic photoreceptor used in these electrophotographic apparatuses, it is less expensive and more manufacturable and safer than conventional electrophotographic photoreceptors using inorganic photoconductive materials such as selenium, selenium-tellurium alloy, selenium-arsenic alloy, cadmium sulfide. An electrophotographic photosensitive member containing an organic photoconductive material such as a phthalocyanine-based pigment having excellent advantages in terms of a charge generating substance has come to dominate.
[0003]
Among such photoreceptors, the function-separated type photoreceptor having a photosensitive layer composed of a charge generation layer that generates a charge upon exposure and a charge transport layer that transports the charge has sensitivity, chargeability, repeat stability, and the like. It is excellent in terms of electrophotographic characteristics, and various configurations have been proposed and put into practical use.
[0004]
In the case of this function-separated type photoreceptor, at present, an undercoat layer is formed on a conductive support layer such as an aluminum base, and then a charge generation layer and a charge transport layer are sequentially formed on the undercoat layer. Many.
[0005]
In particular, in recent years, in electrophotographic apparatuses, contact charging type charging apparatuses that generate less ozone have been used instead of corotron. If the charge generation material (pigment) is not uniformly dispersed in the photosensitive layer of the photoconductor mounted on the electrophotographic apparatus, the conductive support layer has irregularities or dirt on the surface, and the conductive support When the undercoat layer or photosensitive layer formed by coating on the body layer is not uniform over the entire area where the thickness is coated due to coating film unevenness, etc., or when foreign matter is mixed in the photosensitive layer When there is a local defect portion on the photoconductor, a high electric field is locally applied to the defect portion of the photoconductor during contact charging, resulting in an electrical pinhole, which becomes an image quality defect. .
[0006]
In addition, the above pinhole leak is caused when conductive foreign matter such as carbon fiber or carrier powder or dust generated from members constituting the apparatus comes into contact with or penetrates the photoconductor during operation of the electrophotographic apparatus. May also occur.
[0007]
In order to prevent the occurrence of image quality defects in the above-mentioned image and improve the stability of the image quality and the environmental stability with respect to repeated use of the photoreceptor, not only the performance of the photosensitive layer but also the undercoat layer that is the base of the photosensitive layer Therefore, it is necessary to realize an undercoat layer with less charge accumulation by repeated use.
[0008]
Therefore, in order to improve the increase in residual potential while concealing defects in the conductive support layer (base material) and obtain stable electric characteristics, the layer containing the conductive fine powder is replaced with the conductive support layer. A method for forming the photoconductor formed above has been studied.
[0009]
As such a method, for example, a layer containing a conductive fine powder is formed on a conductive support layer such as an aluminum base material, and further a conventional lower layer is formed on the layer containing the conductive fine powder. A method of forming a photoreceptor having an undercoat layer having a two-layer structure in which a layer having the same structure as the undercoat layer is proposed, for example, in Japanese Patent Laid-Open No. 3-46961. In the case of this method, the layer containing the conductive fine powder is made to conceal defects such as irregularities and dirt on the surface of the conductive support layer and the electric resistance is adjusted, and the conventional undercoat layer and A layer having the same configuration is provided with a blocking (charge injection control) function.
[0010]
As another method, only the layer containing conductive fine powder is formed on the conductive support layer as an undercoat layer, and this layer has both the blocking function and the resistance adjusting function described above. For example, such a photoconductor and a method for producing the photoconductor are disclosed in JP-A-9-258469, JP-A-9-96916, and JP-A-2001-75296. ing.
[0011]
[Problems to be solved by the invention]
However, the above-described conventional electrophotographic photosensitive member is still insufficient to obtain sufficient electric characteristics that can withstand repeated use. When the electrophotographic photosensitive member is repeatedly used, the residual potential increases on the image. There was a problem that fogging such as sunspots occurred.
[0012]
That is, since the electrophotographic photosensitive member having the undercoat layer of the two-layer structure described in JP-A-3-45961 is inferior in leakage resistance, the pinhole leakage described above is liable to occur, so that the charging property of the photosensitive member is reduced. There is a problem that the image density decreases with repeated use. Further, in this case, since the structure is a two-layer structure, it takes time and cost to manufacture the photoreceptor.
[0013]
In addition, the electrophotographic photoreceptors described in the above-mentioned JP-A-9-258469, JP-A-9-96916 and JP-A-2001-75296 have a single layer structure as the undercoat layer. Although the manufacturing process can be simplified and the cost can be reduced, it is necessary to provide a resistance control function and a charge injection control function for one layer, and there are restrictions on selecting the constituent material of the undercoat layer. was there.
[0014]
From the viewpoint of preventing the occurrence of pinhole leaks by increasing the leakage resistance of the undercoat layer, it is effective to increase the thickness of the undercoat layer (hereinafter referred to as thickening). In order to obtain good electrical characteristics, it is necessary to reduce the electrical resistance of the undercoat layer. However, when the electrical resistance is reduced, the charge blocking function is lowered and the occurrence of image quality defects such as fogging tends to increase. In addition, there is a problem that it is difficult to form an undercoat layer having a large layer thickness, and mechanical strength after the formation becomes insufficient. Further, when the thickness of the undercoat layer is increased, there is a problem that the sensitivity of the photoreceptor is lowered.
[0015]
Therefore, the layer thickness of the undercoat layer containing conductive metal oxide particles such as titanium oxide particles has been limited to the range of about 0.01 to 20 μm, for example, Japanese Patent Application Laid-Open No. 9-258469, It is said that the thickness of the undercoat layer of the electrophotographic photosensitive member described in JP-A-9-96916 and JP-A-2001-75296 is not preferably larger than 20 μm for the reasons described above.
[0016]
The present invention has been made in view of the above-described problems of the prior art, and is capable of producing an electrophotographic photosensitive member having high durability and high resolution quality that can sufficiently prevent deterioration of electrical characteristics due to repeated use. It is an object to provide a method and an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus obtained thereby.
[0017]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above object, the present inventors have found that the dispersion state of the metal oxide fine particles in the undercoat layer has a great influence on the film resistance of the undercoat layer, and the desired film resistance. It has been found that it is important to control the dispersion state of the metal oxide fine particles in order to obtain an undercoat layer having good electrical characteristics having a value.
[0018]
For example, when metal oxide fine particles are dispersed in the undercoat layer without performing the above surface treatment, the film resistance value of the undercoat layer varies greatly depending on the environment in which it is placed. The value decreases, and the membrane resistance value increases under low humidity conditions. As described above, when the film resistance value of the undercoat layer varies greatly depending on the environment in which it is placed, a serious defect is caused in the image quality, image quality maintenance, and leak resistance of the electrophotographic photosensitive member having the undercoat layer.
[0019]
Furthermore, the present inventors have found that when the metal oxide particles are surface-treated with an organometallic compound having a hydrolyzable functional group, the mixing ratio of the metal oxide particles and the organometallic compound serving as the surface treatment agent is as follows. It has been found that the dispersion state of the metal oxide fine particles in the undercoat layer has a great influence on the electrical properties of the undercoat layer and the electrophotographic photosensitive member provided with the undercoat layer.
[0020]
Then, the inventors of the present invention have provided surface-treated metal oxide particles that have not been focused on by those skilled in the art about the mixing ratio of the metal oxide particles and the organometallic compound and the electrical characteristics of the electrophotographic photosensitive member. X-ray fluorescence analysis data on the surface of the metal element, the characteristic X-ray intensity I1 of the metal element constituting the organometallic compound used for the surface treatment, and the surface treatment Zinc oxide The ratio “I1 / I2” of the characteristic X-ray intensity I2 of the metal element constituting the particle satisfies the condition of a specific range. Zinc oxide When particles (surface-treated ones) are used selectively, Zinc oxide It has been found that the dispersion state of the fine particles can be easily improved.
In this case, the environmental variation of the film resistance value of the undercoat layer can be sufficiently suppressed, and the electrical characteristics of the undercoat layer and the electrophotographic photosensitive member provided with the undercoat layer can be improved easily and with good reproducibility. The present inventors found and reached the present invention.
[0021]
That is, the present invention has a conductive support layer, a photosensitive layer containing a pigment, and an undercoat layer disposed between the conductive support layer and the photosensitive layer, and the undercoat layer. The layer was surface treated with an organometallic compound having a hydrolyzable functional group Zinc oxide A method for producing an electrophotographic photosensitive member containing particles, wherein the surface treatment satisfies the condition represented by the following formula (1): Zinc oxide There is provided a method for producing an electrophotographic photosensitive member, characterized by forming an undercoat layer using particles.
1.0 × 10 ^-6 ≦ (I1 / I2) ≦ 1.0 × 10 ^-3 ... (1)
[In Formula (1),
I1 was surface treated Zinc oxide The characteristic X-ray intensity of the metal element constituting the organometallic compound obtained from the fluorescent X-ray analysis of the particles is shown,
I2 was surface treated Zinc oxide The characteristic X-ray intensity | strength of the metal element which comprises particle | grains is shown. ]
[0022]
In the present specification, the metal oxide particles after surface treatment with an organometallic compound having a hydrolyzable functional group (hereinafter referred to as “hydrolyzable organometallic compound”) are referred to as “metal oxide”. This is referred to as “particle A”. Further, the metal oxide particles before the surface treatment is performed on the metal oxide particles A are referred to as “metal oxide particles B”. Specifically, the metal oxide particles B are zinc oxide particles. . Therefore, the metal oxide particle A is a particle in a state in which a coating using a hydrolyzable organometallic compound as a raw material is formed on part or all of the surface of the metal oxide particle B. Therefore, the characteristic X-rays of all the metal elements constituting the metal oxide particles A obtained from the fluorescent X-ray analysis performed on the metal oxide particles A include the metal elements constituting the metal oxide particles B. And the characteristic X-rays of the metal elements constituting the hydrolyzable organometallic compound.
[0023]
Here, in the present invention, “characteristic X-ray intensity I2” means characteristic X-rays of all metal elements constituting the metal oxide particles A obtained from the fluorescent X-ray analysis performed on the metal oxide particles A. Among these, the intensity | strength of the characteristic X-ray of the metal element which comprised the metal oxide particle B is shown.
[0024]
In the present invention, the “characteristic X-ray intensity I1” means the characteristic X-rays of all the metal elements constituting the metal oxide particles A obtained from the fluorescent X-ray analysis performed on the metal oxide particles A. Of these, the characteristic X-ray intensity of the metal element constituting the hydrolyzable organometallic compound is shown. In addition, when there are a plurality of metal elements constituting the hydrolyzable organometallic compound, the sum of the characteristic X-ray intensities of the metal elements becomes the characteristic X-ray intensity I1. In addition, when a plurality of types of hydrolyzable organometallic compounds are used as raw materials, the total characteristic X-ray intensity of each metal element constituting each metal oxide particle is the characteristic X-ray intensity I1. Furthermore, in the present invention, silicon is also included in the metal element constituting the hydrolyzable organometallic compound.
[0025]
According to the method for producing an electrophotographic photoreceptor of the present invention, the condition of the above formula (1) affects the composition and structure of the surface-treated metal oxide particles A that directly affect the improvement of the electrical properties of the undercoat layer. Therefore, by selectively including only the metal oxide particles A satisfying the condition of the formula (1) in the undercoat layer, the dispersion state of the metal oxide particles A in the undercoat layer can be easily and sufficiently obtained. Can be made uniform. Therefore, it is possible to configure an excellent undercoat layer that has little charge storage property with repeated use. Furthermore, by using this undercoat layer, it is possible to easily and surely produce an electrophotographic photosensitive member having high durability and high resolution quality that can sufficiently prevent deterioration of electric characteristics due to repeated use. it can.
[0026]
Until now, the composition and structure of the coating formed on a part or all of the surface of the metal oxide A have not yet been fully elucidated, so that a metal that can be uniformly dispersed when contained in the undercoat layer. The composition and structure of the oxide particles A could not be clearly determined. Therefore, in the conventional method for producing an electrophotographic photosensitive member, the results of the electrical properties of the obtained undercoat layer and the electrical properties of the electrophotographic photosensitive member are determined based on the production conditions of the metal oxide A, that is, the metal oxide particles B. Feedback was made to the surface treatment conditions (for example, the mixing ratio of the metal oxide particles B and the hydrolyzable organometallic compound, etc.), and the treatment conditions when optimum electrical characteristics were obtained were determined.
[0027]
That is, in the conventional method for producing an electrophotographic photosensitive member, only the surface treatment conditions of the metal oxide particles B are controlled, so that the metal oxide particles A that are well dispersed when contained in the undercoat layer. The undercoat layer and electrophotographic photosensitive member having desired electrical characteristics could not be produced with good reproducibility.
[0028]
In contrast, in the present invention, since the metal oxide particles A are selected and used based on the condition of the formula (1), the dispersion state of the metal oxide particles A when directly contained in the undercoat layer is directly determined. Since it can be controlled to be in a good state, an undercoat layer and an electrophotographic photosensitive member having desired electrical characteristics can be reliably produced with good reproducibility.
[0029]
Further, the fluorescent X-ray analysis of the metal oxide particles A can be performed relatively easily, and the metal oxide particles A satisfying the condition of the formula (1) can be easily selected and used. According to the manufacturing method, an undercoat layer and an electrophotographic photosensitive member having desired electrical characteristics can be easily manufactured.
[0030]
Furthermore, in the electrophotographic photosensitive member obtained by the production method of the present invention, the metal oxide fine particles A are uniformly dispersed in the undercoat layer, and the environmental fluctuation of the film resistance value of the undercoat layer can be sufficiently suppressed. The undercoat layer can be easily thickened. For example, it can be formed by adjusting the thickness of the undercoat layer to, for example, 15 μm or more. With such a thick film, it is possible to easily suppress the occurrence of pinhole leakage by increasing the leakage resistance of the undercoat layer. In addition, such a thick film effectively prevents foreign matter from adhering to the photosensitive layer during use of the electrophotographic photosensitive member and penetrating through the undercoat layer to the conductive support layer. be able to. Therefore, also from the viewpoint that such an undercoat layer can be easily thickened, according to the production method of the present invention, it is possible to sufficiently prevent deterioration in electrical characteristics due to repeated use. An electrophotographic photosensitive member having high resolution and high resolution quality can be obtained.
[0031]
Here, in the present invention, I1 / I2 is 1.0 × 10 6. ^-6 If it is less than this, it becomes impossible to suppress the charge injection from the undercoat layer to the photosensitive layer (charge generation layer), and thus it becomes impossible to prevent the occurrence of image quality defects such as fog. On the other hand, I1 / I2 is 1.0 × 10 ^-3 If it exceeds, the resistance value of the undercoat layer becomes too high, so that it is impossible to sufficiently prevent the residual potential of the undercoat layer from increasing.
[0032]
Further, the present invention is an electrophotographic photoreceptor having a conductive support layer, a photosensitive layer containing a pigment, and an undercoat layer disposed between the conductive support layer and the photosensitive layer, The undercoat layer was surface-treated with an organometallic compound having a hydrolyzable functional group. Zinc oxide Contains particles and is surface treated Zinc oxide Provided is an electrophotographic photosensitive member characterized in that the particles satisfy the condition represented by the following formula (1).
1.0 × 10 ^-6 ≦ (I1 / I2) ≦ 1.0 × 10 ^-3 ... (1)
[In Formula (1),
I1 was surface treated Zinc oxide The characteristic X-ray intensity of the metal element constituting the organometallic compound obtained from the fluorescent X-ray analysis of the particles is shown,
I2 was surface treated Zinc oxide The characteristic X-ray intensity | strength of the metal element which comprises particle | grains is shown. ]
[0033]
Since the electrophotographic photosensitive member of the present invention is manufactured by the above-described manufacturing method of the present invention, it has high durability and high resolution quality that can sufficiently prevent deterioration of electrical characteristics due to repeated use. .
[0034]
Furthermore, the present invention integrally includes the above-described electrophotographic photosensitive member of the present invention and at least one of a charging unit, a developing unit, a cleaning unit, and a charge eliminating unit, and is detachable from the main body of the electrophotographic apparatus. A process cartridge is provided.
[0035]
As a result, the process cartridge of the present invention can obtain high resolution quality without causing fogging such as black spots on the image when repeatedly used.
[0036]
Further, the present invention is an exposure for forming an electrostatic latent image by exposing the electrophotographic photosensitive member of the present invention described above, a charging unit for charging the electrophotographic photosensitive member, and the electrophotographic photosensitive member charged by the charging unit. There is provided an electrophotographic apparatus comprising: a developing unit that develops an electrostatic latent image with toner to form a toner image; and a transfer unit that transfers the toner image to a transfer medium.
[0037]
As a result, the electrophotographic apparatus of the present invention can maintain high resolution quality for a long period of time without causing fogging such as black spots on the copy image when it is used repeatedly.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.
[0039]
The method for producing an electrophotographic photosensitive member of the present invention is a formula of the metal oxide particles A obtained after the surface treatment of the metal oxide particles B in the step of forming the undercoat layer of the electrophotographic photosensitive member. The metal oxide particles A satisfying the condition (1) may be selectively used, and the procedure in the manufacturing process of other components of the electrophotographic photosensitive member other than the undercoat layer and the conditions at that time are not particularly limited. For example, a known technique can be used. Therefore, for a preferred embodiment of the method for producing an electrophotographic photosensitive member of the present invention, a description of a process of forming an undercoat layer serving as a waist portion will be given below. Undercoat layer of each embodiment of the electrophotographic photosensitive member of the present invention This will be done in the explanation of.
[0040]
[First embodiment]
FIG. 1 is a cross-sectional view showing a first embodiment of the electrophotographic photosensitive member of the present invention. As shown in FIG. 1, the electrophotographic photosensitive member 100 includes a conductive support layer 3, an undercoat layer 4, and a photosensitive layer 6. This electrophotographic photosensitive member 100 is manufactured by the above-described method for manufacturing an electrophotographic photosensitive member of the present invention.
[0041]
The conductive support layer 3 is not particularly limited as long as it has conductivity. For example, a metal drum such as aluminum, copper, iron, zinc, or nickel can be used. In addition, drums that have been conductively treated by depositing metals such as aluminum, copper, gold, silver, platinum, palladium, titanium, nickel-chromium, stainless steel, copper-indium, etc. on polymer sheets, paper, plastic, or glass Can be used in the form of a sheet, sheet or plate.
[0042]
In addition, a drum, sheet, or plate that is conductively treated by depositing a conductive metal compound such as indium oxide or tin oxide on a polymer sheet, paper, plastic, or glass, or laminating a metal foil. Can be used. In addition to this, carbon black, indium oxide, tin oxide-antimony oxide powder, metal powder, copper iodide, etc. are dispersed in a binder resin and coated on a polymer sheet, paper, plastic, or glass. A drum-like, sheet-like, or plate-like material subjected to conductive treatment can also be used.
[0043]
Here, when a metal pipe substrate is used as the conductive support layer 3, even if the surface remains as a raw tube, mirror cutting, etching, anodizing, rough cutting, centerless grinding, sand blasting, wet honing are performed in advance. It is preferable to perform a treatment such as a coloring treatment. By performing the surface treatment and roughening the surface of the base material, it is possible to prevent grain-like density spots due to interference light in the photoconductor that may occur when a coherent light source such as a laser beam is used.
[0044]
As described above, the undercoat layer 4 includes the metal oxide particles A obtained by surface-treating the metal oxide particles B using a hydrolyzable organometallic compound, and a binder resin. . The undercoat layer 4 has a function of preventing charge injection from the conductive support layer 3 to the photosensitive layer 6 when the photosensitive layer 6 is charged. The undercoat layer 4 also functions as an adhesive layer that allows the photosensitive layer 6 to be integrally adhered and held to the conductive support layer 3. Further, the undercoat layer 4 has a function of preventing light reflection of the conductive support layer 3.
[0045]
When the thickness of the undercoat layer 4 is as large as possible, it is easy to prevent the effect of the penetrating substance from the outside and the leak resistance is improved. On the other hand, a thin film having a thickness of 10 μm or less is sufficient. Does not have. As described above, according to the manufacturing method of the present invention, the undercoat layer 4 can be easily thickened. From the viewpoint of increasing the leak resistance of the undercoat layer 4 and effectively preventing the occurrence of pinhole leaks, the thickness of the undercoat layer 4 is preferably 15 to 50 μm, and more preferably 20 to 50 μm. .
Here, if the thickness of the undercoat layer 4 exceeds 50 μm, it becomes difficult to maintain good dispersibility of the contained material such as metal oxide particles, and the tendency of image quality deterioration due to an increase in residual charge increases. In this case, the tendency to make the layer thickness uniform is also increased, which may increase the manufacturing cost.
[0046]
However, if it has sufficient leakage resistance and the occurrence of the above-described leakage defect is not a concern, the thickness of the undercoat layer can be set to be thinner than 15 μm. A thin film of about 1 μm can be applied.
[0047]
The binder resin used in the undercoat layer of the electrophotographic photosensitive member of the present invention is an acetal resin such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin. , Acrylic resin, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol resin, phenol-formaldehyde resin, melamine resin, urethane resin, etc. A molecular resin compound, a charge transporting resin having a charge transporting group, a conductive resin such as polyaniline, or the like can be used.
Of these, resins insoluble in the upper coating solvent are preferably used, and phenol resins, phenol-formaldehyde resins, melamine resins, urethane resins, epoxy resins, and the like are particularly preferably used. The mixing ratio of the metal oxide fine particles B and the binder resin can be arbitrarily set within a range in which desired characteristics of the electrophotographic photosensitive member can be obtained.
[0048]
The electrical resistance value of the undercoat layer 4 is 10 ^Four -10 ¹³ Preferably it is Ωcm. ⁸ ~Ten ¹³ More preferably Ωcm, 10 ⁹ ~Ten ¹² More preferably, it is Ωcm. Resistance value is 10 ^Four If it is less than Ωcm, it tends to be difficult to obtain sufficient leak resistance. ¹³ If it exceeds Ωcm, the tendency to cause a rise in residual potential increases. The electrical resistance value of the undercoat layer 4 can be controlled by changing the electrical resistance value of the metal oxide particle A itself and its addition amount, and changing the dispersion state of the metal oxide particle A in the binder resin. it can.
[0049]
The metal oxide particles B are preferably at least one kind of particles selected from the group consisting of tin oxide, titanium oxide and zinc oxide.
[0050]
The metal oxide particles B preferably have an average particle size of 100 nm or less. In addition, a particle size here means an average primary particle size. The metal oxide particles B have a powder resistance value of 10 ² -10 ¹¹ Those having a resistance of Ωcm can be used. From the viewpoint of obtaining the excellent leak resistance of the undercoat layer 4, in particular, the powder resistance value is 10 ^Four -10 ^Ten Those having Ω · cm are preferred. 10 ² If it is less than Ωcm, sufficient leak resistance cannot be obtained. ¹¹ When it exceeds Ωcm, the residual potential tends to increase.
[0051]
Further, since the specific surface area of the metal oxide fine particles B greatly affects the electrophotographic characteristics, the specific surface area of the metal oxide fine particles B is 10 m. ² / G or more is preferable. Specific surface area value is 10m ² If it is less than / g, the tendency to easily cause the charging property of the undercoat layer 4 to decrease is increased.
[0052]
From the viewpoint of suppressing fluctuations in the electrical resistance value of the undercoat layer 4 due to fluctuations in temperature and humidity in the usage environment, the metal oxide particles B are surface-treated with a hydrolyzable organometallic compound to form metal oxide particles A. Yes. By forming the metal oxide particles A by the surface treatment, the dispersion state of the metal oxide particles having a great influence on the electric resistance of the undercoat layer 4 can be easily changed to a state suitable for obtaining the above-described preferable electric resistance value. Can be controlled.
[0053]
Here, the surface treatment refers to a treatment in which a hydrolyzable organometallic compound is adsorbed on the surface of the metal oxide particles B, and a hydrolyzable group of the hydrolyzable organometallic compound is hydrolyzed there. Further, the surface treatment of the metal oxide particles B using the hydrolyzable organometallic compound may be a process for covering the entire metal oxide fine particles B or a process for covering a part thereof.
[0054]
In the present invention, as the hydrolyzable organometallic compound, those represented by the following general formula (I) are preferable.
RpMYq (I)
[0055]
In the formula (II), R represents an organic group, M represents a metal element or silicon, Y represents a hydrolyzable functional group, p and q each represents an integer of 1 to 4, and the sum of p and q Corresponds to the valence of M.
[0056]
Examples of the organic group R include alkyl groups such as methyl, ethyl, propyl, butyl, and octyl groups, alkenyl groups such as vinyl and allyl groups, cycloalkyl groups such as cyclohexyl groups, phenyl groups, and naphthyl groups. Heterocyclic groups such as aryl group such as aryl group such as aryl group, arylalkenyl group such as benzyl group and phenylethyl group, arylalkenyl group such as styryl group, furyl group, thienyl group, pyrrolidinyl group and imidazolyl group The organic compound residue is not particularly limited. The organic group R in the hydrolyzable organometallic compound may be one type selected from the above organic compound residues, or two or more types.
[0057]
Examples of the hydrolyzable functional group Y include ether groups such as methoxy group, ethoxy group, propoxy group, butoxy group, cyclohexyloxy group, phenoxy group, benzyloxy group, acetoxy group, propionylaxyl group, acryloxy group, methacryloxy group. Groups, benzoyloxy groups, methanesulfonyloxy groups, benzenesulfonyloxy groups, ester groups such as benzyloxycarbonyl groups, halogen atoms such as chlorine atoms, and the like.
[0058]
Further, M is not particularly limited as long as it is not an alkali metal, and silicon, zirconium, titanium, aluminum, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, ruthenium, Examples include metals such as rhodium, palladium, indium, tin, and platinum.
[0059]
And as a hydrolysable organometallic compound which has said organic group R and hydrolysable functional group Y, the silane coupling agent and titanate coupling agent which substituted said organic group and hydrolysable functional group are mentioned. It is preferably at least one selected from the group consisting of an aluminate coupling agent and an organic zirconium compound, and more preferably a silane coupling agent. These hydrolyzable organometallic compounds can be used alone or in combination of two or more.
[0060]
Examples of silane coupling agents include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidoxypropyl. Trimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, and the like.
[0061]
Examples of titanate coupling agents include isopropyl triisostearoyl titanate, bis (dioctyl pyrophosphate), isopropyl tri (N-aminoethyl-aminoethyl) titanate, and the like.
[0062]
Examples of the aluminate coupling agent include acetoalkoxy aluminium diisopropylate.
[0063]
Of the hydrolyzable organometallic compounds, a silane coupling agent is preferably used, a silane coupling agent having a mercapto group is more preferably used, and γ-mercaptopropyltrimethoxysilane is preferably used.
[0064]
In addition, as described above, the amount of the hydrolyzable organic metal compound used for the surface treatment is an amount capable of obtaining the metal oxide particles A satisfying the condition of the formula (1). It is optimized and set according to the surface treatment conditions such as the combination of the metal compound and the metal oxide particles B, the temperature of the surface treatment reaction, the apparatus used for the surface treatment and the scale of the metal oxide particles A to be prepared.
[0065]
Next, a surface treatment method for the metal oxide particles B will be described. The method of surface treatment of the metal oxide particles B with a hydrolyzable organometallic compound is not particularly limited, and for example, a known method such as a dry method, a wet method, or a gas phase method may be used.
[0066]
In the present invention, for example, after the surface treatment of the metal oxide particles B, the metal oxide particles A satisfying the formula (1) may be separated from the obtained metal oxide particles A. However, for example, if possible, the surface treatment conditions of the metal oxide particles B with good reproducibility for obtaining the metal oxide particles A satisfying the condition of the formula (1) are easily optimized and grasped in advance. If it can be used, all of the metal oxide particles A obtained by the surface treatment conditions of the optimized metal oxide particles B may be used for forming the undercoat layer.
[0067]
For example, an example of a procedure for performing surface treatment based on a dry method will be described. First, before the surface treatment, the metal oxide particles B are preliminarily dried at a temperature of 100 to 150 ° C. to remove surface adsorbed water. By removing the surface adsorbed water before the treatment, the hydrolyzable organometallic compound can be uniformly adsorbed on the surface of the metal oxide particles B. At this time, the metal oxide particles B may be preliminarily dried while stirring with a mixer having a large shearing force.
[0068]
Next, the hydrolyzable organometallic compound is adsorbed on the surface of the metal oxide particles B. At this time, while stirring the metal oxide particles B with a mixer having a large shearing force, the hydrolyzable organometallic compound is sprayed with dry air or nitrogen gas, or the hydrolyzable organometallic compound is dissolved in a solvent (organic solvent, A liquid dissolved in water or the like is sprayed with dry air or nitrogen gas. Thereby, the hydrolyzable organometallic compound is uniformly adsorbed on the surface of the metal oxide particles B.
[0069]
The temperature at which the hydrolyzable organometallic compound is adsorbed on the surface of the metal oxide particles B is preferably 50 ° C or higher. Moreover, when using a solvent, it is preferable to carry out at the temperature of the boiling point vicinity of a solvent.
[0070]
Then, a baking process is performed at a temperature of 100 ° C. or higher. Thereby, the hydrolysis reaction of the hydrolyzable organometallic compound can sufficiently proceed. The baking treatment is preferably performed at a temperature of 150 to 250 ° C. If it is lower than 150 ° C., the hydrolysis reaction of the hydrolyzable organometallic compound may not be sufficiently advanced. If it exceeds 250 ° C, the hydrolyzable organometallic compound may be decomposed.
[0071]
Next, the surface-treated metal oxide particles A are pulverized as necessary. Thereby, since the aggregate of the metal oxide particles A can be pulverized, the dispersibility of the metal oxide particles in the undercoat layer 4 can be improved.
[0072]
Next, an example of a procedure for performing a surface treatment based on a wet method will be described. First, the metal oxide fine particles B are dispersed in a solvent by using an ultrasonic wave, a sand mill, an attritor, a ball mill, etc., and then a liquid containing a hydrolyzable organometallic compound is added thereto and stirred. Allow the processing reaction to proceed. Thereafter, the solvent is distilled off from this liquid by distillation. Moreover, you may bake the solid substance obtained after solvent removal at 100 degreeC or more further. Further, in this wet method as well as the dry method, the surface adsorbed water of the metal oxide fine particles B may be removed before the surface treatment. As this surface adsorbed water removal method, in addition to the removal by heating and drying as in the dry method, a method of removing with stirring and heating in the solvent used for the surface treatment, a method of removing by azeotropy with the solvent, and the like can be mentioned. .
[0073]
The undercoat layer 4 can contain other additives for improving its electrical characteristics, improving shape stability in the use environment, and improving image quality.
[0074]
For example, quinone compounds such as chloranil, bromoanil, anthraquinone, tetracyanoquinodimethane compounds, fluorenone compounds such as 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2 -(4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3,4-oxadiazole, 2 Oxadiazole compounds such as 1,5-bis (4-diethylaminophenyl) 1,3,4 oxadiazole, xanthone compounds, thiophene compounds, 3,3 ', 5,5' tetra-t-butyldiphenoquinone Electron transporting substances such as diphenoquinone compounds such as polycyclic condensation systems, electron transporting pigments such as azo systems, zirconium chelate compounds, titanium chelate compounds, aluminum chelate compounds, titanium alkoxide compounds, organic titanium compounds, etc. Can be contained.
[0075]
Examples of the titanium chelate compound include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt. , Titanium lactate, titanium lactate ethyl ester, titanium triethanolamate, polyhydroxy titanium stearate and the like.
[0076]
Examples of the aluminum chelate compound include aluminum isopropylate, monobutoxy aluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) and the like. These compounds can be used alone or as a mixture or polycondensate of a plurality of compounds.
[0077]
In addition, from the viewpoint of preventing foreign substances such as conductive powder from the outside from penetrating the photosensitive member, which contribute to current leakage during contact charging, and forming a highly durable undercoat layer 4, the undercoat layer It is effective to increase the hardness of 4, and the Vickers hardness of the undercoat layer 4 is 30 or more, preferably 35 or more, as an index of hardness.
[0078]
Further, from the viewpoint of preventing moire images, the surface roughness of the undercoat layer 4 is adjusted to 1/4 n (n is the refractive index of the upper layer) to λ when the exposure laser wavelength λ used is used. It is preferable. The surface here is the surface of the undercoat layer 4 on the photosensitive layer 6 side. Moreover, you may add the resin particle in the undercoat layer 4 for this surface roughness adjustment. As the resin particles, silicone resin particles, cross-linked polymethyl methacrylate resin (PMMA) particles, and the like can be used.
[0079]
Further, the surface of the undercoat layer 4 may be polished to adjust the surface roughness. As a polishing method, buffing, sand blasting, wet honing, grinding, or the like can be used.
[0080]
Next, a method for forming the undercoat layer 4 (a process for forming the undercoat layer 4) will be described. The undercoat layer 4 is a particle satisfying the formula (1) among the metal oxides A obtained after surface-treating the metal oxide particles B with at least one hydrolyzable metal compound. Can be formed by coating the conductive support layer 3 with a coating solution obtained by dispersing the above in the binder resin described above.
[0081]
As a solvent for adjusting the coating solution for forming the undercoat layer 4, a known organic solvent, for example, alcohol, aromatic, halogenated hydrocarbon, ketone, ketone alcohol, ether, ester, etc. Can be selected arbitrarily.
[0082]
For example, methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, Usual organic solvents such as methylene chloride, chloroform, chlorobenzene, and toluene can be used.
[0083]
These solvents used for dispersion can be used alone or in admixture of two or more. When mixing, any solvent can be used as long as it can dissolve the binder resin as the mixed solvent.
[0084]
As a method for dispersing the metal oxide particles A in the binder resin, methods such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker can be used. Furthermore, as an application method used when providing this undercoat layer, a usual method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, or a curtain coating method is used. Can be used.
[0085]
Next, the photosensitive layer 6 will be described. As shown in FIG. 1, the photosensitive layer 6 includes a charge generation layer 1 and a charge transport layer 2.
[0086]
The pigment (charge generating material) contained in the charge generation layer 1 is not particularly limited, and a known pigment can be used.
[0087]
In a photoreceptor using infrared light, for example, a phthalocyanine pigment, a squarylium pigment, a bisazo pigment, a trisazo pigment, a perylene pigment, or a dithioketopyrrolopyrrole pigment can be used. In the photoreceptor using a visible light laser, for example, a condensed polycyclic pigment, a bisazo pigment, a perylene pigment, trigonal selenium, a dye-sensitized metal oxide, or the like can be used.
[0088]
Among the pigments described above, it is preferable to use a phthalocyanine pigment because an excellent image can be obtained. This makes it easy to construct an electrophotographic photosensitive member that is particularly sensitive and can stably obtain good image quality even when used repeatedly.
[0089]
Phthalocyanine pigments generally have several crystal forms, and any of these crystal forms can be used as long as it is a crystal form capable of obtaining a sensitivity suitable for the purpose. In particular, among the phthalocyanine pigments, phthalocyanine pigments represented by the following formulas (1) to (6) are preferably used.
[0090]
[Chemical 1]

[0091]
In the above formulas (1) to (6), the chlorogallium phthalocyanine has a Bragg angle (2θ ± 0.2 °) of 7.4 °, 16.6 °, 25.5 °, 28.3 in the X-ray diffraction spectrum using Cukα rays. Those having at least a diffraction peak at a position of ° are preferable. In addition, as titanyl phthalocyanine, in the X-ray diffraction spectrum using Cukα ray, it has at least a diffraction peak at a position where the value of Bragg angle (2θ ± 0.2 °) is 9.6 °, 24.1 °, 27.3 °, and the maximum peak Is preferably 27.3 °.
[0092]
In addition to the phthalocyanine pigments represented by the following formulas (1) to (6), hydroxygallium phthalocyanine in which a Cl atom bonded to Ga serving as a coordination center in formula (4) is substituted with an —OH group is also preferable. As such hydroxygallium phthalocyanine, in the X-ray diffraction spectrum using Cukα ray, the values of Bragg angles (2θ ± 0.2 °) are 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 °, 25.1 °, 28.1. Those having at least a diffraction peak at a position of ° are preferable.
[0093]
Furthermore, such pigments can be obtained by mechanically dry-pulverizing pigment crystals produced by a known method with an automatic mortar, planetary mill, vibration mill, CF mill, roller mill, sand mill, kneader, or the like. It can be produced by wet pulverization using a ball mill, mortar, sand mill, kneader or the like together with a solvent.
[0094]
Solvents used in the above wet grinding treatment include aromatics (toluene, chlorobenzene, etc.), amides (dimethylformamide, N-methylpyrrolidone, etc.), aliphatic alcohols (methanol, ethanol, butanol, etc.), fatty acids Polyhydric alcohols (ethylene glycol, glycerin, polyethylene glycol, etc.), aromatic alcohols (benzyl alcohol, phenethyl alcohol, etc.), esters (acetic ester, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, etc.), dimethyl Examples thereof include sulfoxides, ethers (diethyl ether, tetrahydrofuran, etc.), several mixed systems, and mixed systems of water and these organic solvents.
[0095]
Moreover, this solvent is used in 1-200 mass parts with respect to a pigment crystal, Preferably it is 10-100 mass parts. Further, the treatment temperature is 0 ° C. to the boiling point of the solvent, preferably 10 to 60 ° C. In addition, grinding aids such as sodium chloride and sodium nitrate can be used during grinding.
[0096]
The grinding aid may be used 0.5 to 20 times, preferably 1 to 10 times the pigment. In addition, the pigment crystals produced by a known method can be controlled by combining acid pasting or acid pasting with dry pulverization or wet pulverization as described above.
[0097]
As an acid used for acid pasting, sulfuric acid is preferable, and a concentration (mass percent concentration) of 70 to 100%, preferably 95 to 100% is used, and a dissolution temperature is -20 to 100 ° C, preferably -20 to 20%. It is set in the range of 60 ° C. The amount of concentrated sulfuric acid is set in the range of 1 to 100 times, preferably 3 to 50 times the weight of the pigment crystals. As the solvent to be precipitated, water, a mixed solvent of water and an organic solvent, ammonia water or the like is used in an arbitrary amount. The temperature for precipitation is not particularly limited, but it is preferably cooled with ice or the like in order to prevent heat generation.
[0098]
The pigment content is preferably 10 to 90 mass%, more preferably 40 to 70 mass%, based on the total mass of the charge generation layer 1. When the pigment content is less than the lower limit of the above numerical range, it is difficult to obtain sufficient sensitivity. On the other hand, when the pigment content exceeds the upper limit of the above numerical range, there is a greater tendency for adverse effects such as a decrease in chargeability and a decrease in sensitivity.
[0099]
The binder resin contained in the charge generation layer 1 is not particularly limited as long as it is an insulating resin, and can be selected from a wide range of insulating resins. For example, preferable binder resins include polyvinyl acetal resin, polyarylate resin (polycondensate of bisphenol A and phthalic acid, etc.), polycarbonate resin, polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyamide resin, acrylic resin. Examples thereof include insulating resins such as resins, polyacrylamide resins, polyvinyl pyridine resins, cellulose resins, urethane resins, epoxy resins, caseins, polyvinyl alcohol resins, and polyvinyl pyrrolidone resins.
[0100]
As the binder resin for the charge generation layer 1, polyvinyl acetal resin and vinyl chloride-vinyl acetate copolymer are particularly preferably used from the viewpoint of dispersibility of the pigment. In addition, you may use said binder resin individually or in mixture of 2 or more types.
[0101]
In the case of the charge generation layer 1, the blending ratio (mass ratio) of the pigment and the binder resin is preferably in the range of 10: 1 to 1:10. When the mass of the binder resin with respect to the mass of the pigment is less than the value indicated by the above blending ratio, there is a greater tendency for adverse effects such as poor film formability to occur. On the other hand, when the mass of the binder resin exceeds the value indicated by the above-mentioned blending ratio with respect to the mass of the pigment, the content in the film is relatively reduced, and thus there is a tendency that sufficient sensitivity cannot be obtained.
[0102]
Further, the organic solvent contained in the coating liquid for forming the charge generation layer 1 is a solvent that can dissolve the binder resin and does not affect the crystal form of the pigment (charge generation material). If it is, it will not specifically limit, A well-known organic solvent can be used.
[0103]
For example, it can be arbitrarily selected from alcohols, aromatics, halogenated hydrocarbons, ketones, ketone alcohols, ethers, esters, and the like. Specifically, for example, methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, n-butyl acetate Ordinary organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene can be used. These organic solvents can be used alone or in combination of two or more.
[0104]
To the charge generation layer 1, other additives same as those described in the description of the undercoat layer 4 can be added for the purpose of improving the electrical characteristics and improving the image quality.
[0105]
Furthermore, the layer thickness of the charge generation layer 1 is preferably 0.05 to 5 μm, and more preferably 0.1 to 1 μm, in order to give good electrical characteristics and image quality. If the thickness of the charge generation layer 1 is less than 0.05 μm, sufficient sensitivity cannot be given. On the other hand, when the thickness of the charge generation layer 1 exceeds 5 μm, it is easy to cause problems such as poor charging properties.
[0106]
The charge generation layer 1 is prepared by mixing a pigment (charge generation material), an organic solvent, a binder resin, an additive (for example, a pigment dispersion aid), etc., and preparing a coating solution on the undercoat layer 4. It can be formed by coating and further drying. The charge generation layer 1 can also be formed by vacuum depositing a charge generation material on the undercoat layer 4.
[0107]
In order to prepare a coating solution for forming the charge generation layer 1, it is mixed with a pigment, a binder resin, an organic solvent, other additives (for example, a pigment dispersion aid) and the like. As a method for highly dispersing the pigment in the liquid, a dispersion method such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, or a paint shaker can be used.
[0108]
Furthermore, from the viewpoint of film formability, the particle diameter of the dispersed particles such as pigments contained in the coating liquid for forming the charge generation layer 1 is preferably 0.5 μm or less, more preferably 0.3 μm or less. Preferably, it is 0.15 μm or less. When the particle diameter of the dispersed particles exceeds 0.5 μm, the film forming property of the charge generation layer 1 is deteriorated and image quality defects are likely to occur.
[0109]
The coating method for applying the coating solution for forming the charge generation layer 1 onto the undercoat layer 4 is blade coating method, wire bar coating method, spray coating method, dip coating method, bead coating method, air knife coating. Ordinary methods such as a method and a curtain coating method can be used.
[0110]
Next, the charge transport layer 2 will be described. The charge transport material contained in the charge transport layer 2 is not particularly limited, and a known material can be used.
[0111]
For example, oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazoline, 1- [pyridyl- (2)] -3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazolin derivatives such as pyrazoline, triphenylamine, tri (P-methyl) phenylamine, N, N'-bis (3,4-dimethylphenyl) ) Aromatic tertiary amino compounds such as biphenyl-4-amine, dibenzylaniline, 9,9-dimethyl-N, N'-di (p-tolyl) fluorenon-2-amine, N, N'-diphenyl- Aromatic tertiary diamino compounds such as N, N'-bis (3-methylphenyl)-[1,1-biphenyl] -4,4'-diamine, 3- (4'dimethylaminophenyl) -5,6 1,2,4-triazine derivatives such as -di- (4'-methoxyphenyl) -1,2,4-triazine, 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, 4-diphenylamino Hydrazone derivatives such as benzaldehyde-1,1-diphenylhydrazone, [p- (diethylamino) phenyl] (1-naphthyl) phenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styryl-quinazoline, 6-hydroxy-2,3 Benzofuran derivatives such as -di (p-methoxyphenyl) -benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N'-diphenylaniline, enamine derivatives, carbazole such as N-ethylcarbazole Derivatives, hole transport materials such as poly-N-vinylcarbazole and its derivatives, quinone compounds such as chloranil, bromoanil, anthraquinone, tetracyanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4 , 5,7-tetranitro-9-fluorenone, 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-biolone (4-naphthyl) -1,3,4-oxadiazole, oxadiazole compounds such as 2,5-bis (4-diethylaminophenyl) 1,3,4 oxadiazole, xanthone compounds, thiophene compounds, And electron transport materials such as diphenoquinone compounds such as 3,3 ′, 5,5 ′ tetra-t-butyldiphenoquinone.
[0112]
Furthermore, examples of the charge transport material include a polymer having the basic structure of the compound exemplified above in the main chain or side chain. These charge transport materials can be used alone or in combination of two or more.
[0113]
Moreover, the binder resin contained in the charge transport layer 2 is not particularly limited, and a known resin can be used, but a resin capable of forming an electrical insulating film is preferable.
[0114]
For example, polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-acetic acid Vinyl copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin. Silicon-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-carbazole, polyvinyl butyral, polyvinyl formal, polysulfone, casein, gelatin, polyvinyl alcohol, ethyl cellulose, phenol resin, polyamide, carboxymethyl cellulose, vinylidene chloride System polymer wax, polyurethane and the like.
[0115]
These binder resins can be used alone or in combination of two or more. In particular, a polycarbonate resin, a polyester resin, a methacrylic resin, and an acrylic resin are preferably used because they are excellent in compatibility with a charge transport material, solubility in a solvent, and strength.
[0116]
Further, the blending ratio (mass ratio) of the binder resin and the charge transporting material can be arbitrarily set in consideration of a decrease in electrical characteristics and a decrease in film strength. The layer thickness of the charge transport layer 2 is preferably 5 to 50 μm, and more preferably 10 to 35 μm. Is appropriate.
[0117]
The charge transport layer 2 can be formed by preparing a coating liquid by mixing a charge transport material, an organic solvent, a binder resin, and the like, coating this on the charge generation layer 1 and further drying.
[0118]
In order to prepare a coating solution for forming the charge transport layer 2, it is mixed with a charge transport material, an organic solvent, a binder resin and the like. As a method for highly dispersing the charge transport material in the liquid, a dispersion method such as a roll mill, a ball mill, a vibrating ball mill, an attritor, a sand mill, a colloid mill, or a paint shaker can be used.
[0119]
Furthermore, from the viewpoint of film formability, the particle diameter of dispersed particles such as pigments contained in the coating liquid for forming the charge transport layer 2 is preferably 0.5 μm or less, more preferably 0.3 μm or less. Preferably, it is 0.15 μm or less. When the particle diameter of the dispersed particles exceeds 0.5 μm, the film formability of the charge transport layer 2 is deteriorated and image quality defects are likely to occur.
[0120]
Furthermore, as a solvent used for the coating liquid for forming the charge transport layer 2, ordinary organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like can be used alone or in combination.
[0121]
As a method for applying the charge transport layer 2, a normal method such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, or a curtain coating method can be used.
[0122]
[Second Embodiment]
FIG. 2 is a cross-sectional view showing a second embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 110 shown in FIG. 2 has the same configuration as the electrophotographic photoreceptor 100 shown in FIG. 1 except that the photosensitive layer 6 has a single layer structure.
[0123]
The photosensitive layer 6 shown in FIG. 2 is a layer that contains both the charge generating material and the charge transporting material contained in the charge generating layer 1 and the charge transporting layer 2 shown in FIG.
[0124]
When the photosensitive layer 6 is thus a single layer type, the pigment content is preferably 0.1 to 50% by mass, and 1 to 20% by mass with respect to the total mass of the photosensitive layer 6. More preferably. Moreover, when the pigment content is less than the lower limit of the above numerical range, it is difficult to obtain sufficient sensitivity. On the other hand, when the pigment content exceeds the upper limit of the above numerical range, the tendency for adverse effects such as a decrease in chargeability and a decrease in sensitivity increases.
[0125]
In addition, when the photosensitive layer 6 is a single layer type as described above, a polycarbonate resin and a methacrylic resin are particularly preferably used as the binder resin from the viewpoint of compatibility with the hole transporting material. Furthermore, these resins may be selected from organic photoconductive polymers such as poly-N-vinyl carbazole, polyvinyl anthracene, polyvinyl pyrene and polysilane. In addition, you may use said binder resin individually or in mixture of 2 or more types.
[0126]
The photosensitive layer 6 is also prepared by mixing the above-described charge transporting material, the above-described charge transporting material, the above-mentioned organic solvent, the binder resin, etc., and preparing a coating solution on the conductive support layer 3 by the same method as described above. It can be formed by coating and further drying.
[0127]
[Third embodiment]
FIG. 3 is a cross-sectional view showing a third embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 120 shown in FIG. 3 has the same configuration as the electrophotographic photoreceptor 100 shown in FIG. 1 except that the protective layer 5 is provided on the photosensitive layer 6.
[0128]
The protective layer 5 is used to prevent chemical change of the charge transport layer 2 when the electrophotographic photosensitive member 120 is charged or to further improve the mechanical strength of the photosensitive layer 6. The protective layer 5 is formed by applying a coating solution containing a conductive material in a suitable binder resin on the photosensitive layer 6.
[0129]
The conductive material is not particularly limited, and examples thereof include metallocene compounds such as N, N′-dimethylferrocene, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1, Aromatic amine compounds such as 1'-biphenyl] -4,4'-diamine, molybdenum oxide, tungsten oxide, antimony oxide, tin oxide, titanium oxide, indium oxide, tin oxide and antimony, solid solution of barium sulfate and antimony oxide Carrier, mixture of the above metal oxides, titanium oxide, tin oxide, zinc oxide or barium sulfate mixed in a single particle, or titanium oxide, tin oxide, zinc oxide or barium sulfate The above-mentioned metal oxide is coated on a single particle.
[0130]
The binder resin used for the protective layer 5 is polyamide resin, polyvinyl acetal resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, polyimide resin, polyamideimide resin. Known resins such as these are used. These can also be used by cross-linking each other as necessary.
[0131]
The thickness of the protective layer 5 is preferably 1 to 20 μm, and more preferably 2 to 10 μm. As a coating method of the coating liquid for forming this protective layer 5, a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, etc. are used. The method can be used.
[0132]
Moreover, as a solvent used for the coating liquid for forming the protective layer 5, normal organic solvents such as dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene and toluene can be used alone or in combination of two or more. It is preferable to use a solvent that hardly dissolves the photosensitive layer 6 to which the coating solution is applied.
[0133]
[Fourth embodiment]
FIG. 4 is a cross-sectional view showing a second embodiment of the electrophotographic photosensitive member of the present invention. The electrophotographic photoreceptor 130 shown in FIG. 4 has the same configuration as the electrophotographic photoreceptor 110 shown in FIG. 2 except that the photosensitive layer 6 has a single layer structure and the protective layer 5 is provided on the photosensitive layer 6.
[0134]
[Fifth embodiment]
FIG. 5 is a sectional view showing a fifth embodiment of the electrophotographic photosensitive member of the present invention. An electrophotographic photoreceptor 140 shown in FIG. 5 has the same configuration as the electrophotographic photoreceptor 100 shown in FIG. 1 except that an intermediate layer 42 is provided between the photosensitive layer 6 and the undercoat layer 4. The intermediate layer 42 is provided to improve the electrical characteristics of the photoreceptor 140, improve the image quality, and improve the adhesion of the photosensitive layer 6.
[0135]
The constituent material of the intermediate layer 42 is not particularly limited, and can be arbitrarily selected from synthetic resin, organic substance or inorganic substance powder, electron transporting substance, and the like.
[0136]
Synthetic resins for the intermediate layer 42 include acetal resins such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, and polyvinyl acetate resin. , Vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, polymer resin compound such as melamine resin, zirconium chelate compound, titanium chelate compound, aluminum chelate compound, titanium alkoxide compound, Known materials such as organic titanium compounds and silane coupling agents can be used.
[0137]
These compounds can be used alone or as a mixture or polycondensate of a plurality of compounds. Among these, zirconium chelate compounds and silane coupling agents are excellent in performance, such as low residual potential, little potential change due to environment, and little potential change due to repeated use.
[0138]
Examples of the above silane coupling agents include vinyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxy Propyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl ) -γ-aminopropylmethylmethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, and the like.
[0139]
Among these, silicon compounds particularly preferably used include vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, Examples include silane coupling agents such as N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane.
[0140]
Zirconium chelate compounds include zirconium butoxide, zirconium zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl acetoacetate butoxide, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octoate, naphthenic acid. Zirconium, zirconium laurate, zirconium stearate, zirconium isostearate, methacrylate zirconium butoxide, stearate zirconium butoxide, isostearate zirconium butoxide and the like.
[0141]
Titanium chelate compounds include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt, titanium Examples include lactate, titanium lactate ethyl ester, titanium triethanolamate, and polyhydroxytitanium stearate.
[0142]
Examples of the aluminum chelate compound include aluminum isopropylate, monobutoxy aluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, and aluminum tris (ethyl acetoacetate).
[0143]
In the intermediate layer 42, fine powders of various organic compounds or fine powders of inorganic compounds can be added for the purpose of improving electrical characteristics and light scattering properties. In particular, white pigments such as titanium oxide, zinc oxide, zinc white, zinc sulfide, lead white and lithopone, inorganic pigments as extender pigments such as alumina, calcium carbonate and barium sulfate, Teflon resin particles, benzoguanamine resin particles, styrene resin particles Etc. are effective.
[0144]
The added fine powder has a particle size of 0.01 to 2 μm. The fine powder is added as necessary, but the addition amount is preferably 10 to 90% by mass, and 30 to 80% by mass with respect to the total mass of the solid content of the intermediate layer 42. It is more preferable.
[0145]
In addition, it is also effective from the viewpoint of low residual potential and environmental stability to include the above-described electron transporting substance, electron transporting pigment, and the like in the intermediate layer 42. Furthermore, the thickness of the intermediate layer 42 is preferably 0.01 to 30 μm, and more preferably 0.05 to 25 μm.
[0146]
In addition, when preparing a coating liquid for forming the intermediate layer 42, when a fine powdery substance is added, it is added to a solution in which a resin component is dissolved and subjected to a dispersion treatment. As the dispersion treatment method, methods such as a roll mill, a ball mill, a vibrating ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker can be used.
[0147]
Further, the intermediate layer 42 can be formed by applying a coating solution for forming the intermediate layer 42 on the conductive support layer 3 and drying it. As a coating method at this time, usual methods such as a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, and the like can be used.
[0148]
[Sixth embodiment]
FIG. 6 is a sectional view showing a sixth embodiment of the electrophotographic photosensitive member of the present invention. An electrophotographic photoreceptor 150 shown in FIG. 6 has the same structure as the electrophotographic photoreceptor 100 shown in FIG. 1 except that the photosensitive layer 6 has a single layer structure and an intermediate layer 42 is provided between the photosensitive layer 6 and the undercoat layer 4. It has the same configuration.
[0149]
The intermediate layer 42 has a configuration similar to that of the photoreceptor 140 shown in FIG.
[0150]
[Seventh embodiment]
FIG. 7 is a sectional view showing a seventh embodiment of the electrophotographic photosensitive member of the present invention.
[0151]
The electrophotographic photoreceptor 160 shown in FIG. 7 has the protective layer 5 on the photosensitive layer 6 and the intermediate layer 42 between the photosensitive layer 6 and the undercoat layer 4. 100 has the same configuration.
[0152]
The intermediate layer 42 has the same configuration as the intermediate layer 42 of the photoreceptor 140 shown in FIG. Further, the protective layer 5 has the same configuration as the protective layer 5 of the photosensitive member 120 shown in FIG.
[0153]
[Eighth embodiment]
FIG. 8 is a cross-sectional view showing a seventh embodiment of the electrophotographic photosensitive member of the present invention.
[0154]
An electrophotographic photoreceptor 170 shown in FIG. 8 is provided with the exception that the protective layer 5 is provided on the photosensitive layer 6, the photosensitive layer 6 has a single layer structure, and the intermediate layer 42 is provided between the photosensitive layer 6 and the undercoat layer 4. The configuration is the same as that of the electrophotographic photoreceptor 100 shown in FIG.
[0155]
The intermediate layer 42 has the same configuration as the intermediate layer 42 of the photoreceptor 140 shown in FIG. Further, the protective layer 5 has the same configuration as the protective layer 5 of the photosensitive member 120 shown in FIG. Further, the photosensitive layer 6 has the same configuration as that of the photosensitive layer 6 of the photosensitive member 110 shown in FIG.
[0156]
The preferred embodiment of the electrophotographic photoreceptor of the present invention has been described in detail above, but the electrophotographic photoreceptor of the present invention is not limited to the above embodiment.
[0157]
For example, in the case where the photosensitive layer of the electrophotographic photosensitive member of the present invention has a two-layer structure such as the photosensitive members 100, 120, and 130 shown in FIGS. 1, 3, and 5, FIGS. b) In any case of a single-layer structure such as the photoconductors 110, 130, and 150 shown in FIG. 6, the photoconductor is deteriorated by ozone, oxidizing gas, or light / heat generated in the electrophotographic apparatus. Additives such as antioxidants, light stabilizers, heat stabilizers and the like may be added for the purpose of preventing odors.
[0158]
For example, examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, and organic phosphorus compounds.
[0159]
Specific examples of antioxidant compounds include 2,6-di-t-butyl-4-methylphenol, styrenated phenol, n-octadecyl-3- (3 ', 5'-dithiophene for phenolic antioxidants. -t-butyl 4'-hydroxyphenyl) -propionate, 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2-t-butyl-6- (3'-t-butyl -5'-methyl-2'-hydroxybenzyl) -4-methylphenyl acrylate, 4,4'-butylidene-bis- (3-methyl-6-t-butyl-phenol), 4,4'-thio-bis -(3-Methyl 6-t-butylphenol), 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetrakis- [methylene-3- (3 ' , 5'-Di-t-butyl-4'-hydroxy-phenyl) propionate] -methane, 3,9-bis [2- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyl Oxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspir B [5,5] undecane.
[0160]
Examples of hindered amine compounds include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy]- 2,2,6,6-tetramethylpiperidine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, succinate, Poly [[6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diimyl] [(2,2,6,6-tetramethyl-4-piperidyl ) Imino] hexamethylene [(2,3,6,6-tetramethyl-4-piperidyl) imino]], 2- (3,5-di-t-butyl- 4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), N, N'-bis (3-aminopropyl) ethylenediamine-2,4- Examples thereof include bis [N-butyl-N- (1,2,2,6,6, -pentamethyl-4piperidyl) amino] -6-chloro-1,3,5-triazine condensate.
[0161]
Organic sulfur antioxidants include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, pentaerythritol-tetrakis -(β-lauryl-thiopropionate), ditridecyl-3,3′-thiodipropionate, 2-mercaptobenzimidazole and the like. Examples of organophosphorus antioxidants include trisnonylphenyl phosfeto, triphenyl phosfeto, and tris (2,4-di-t-butylphenyl) -phosfte.
[0162]
Organic sulfur-based and organic phosphorus-based antioxidants are referred to as secondary antioxidants, and a synergistic effect can be obtained by using them together with primary antioxidants such as phenols or amines.
[0163]
Examples of the light stabilizer include benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine derivatives. For example, examples of the benzophenone light stabilizer include 2-hydroxy-4-methoxy benzophenone, 2-hydroxy-4-octoxy benzophenone, and 2,2′-di-hydroxy-4-methoxy benzophenone.
[0164]
Benzotriazole-based light stabilizers include 2-(-2'-hydroxy-5'methyl phenyl-)-benzotriazole, 2- [2'-hydroxy-3 '-(3'',4'', 5 '', 6 ''-tetra-hydrophthalimido-methyl) -5'-methylphenyl] -benzotriazole, 2-(-2'-hydroxy-3'-t-butyl 5'-methylphenyl-)-5- Chlorobenzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl-)-5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-t-butylphenyl) -)-Benzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) -benzotriazole, 2- (2'-hydroxy 3 ', 5'-di-t-amylphenyl-)-benzotriazole Etc.
[0165]
Other compounds include 2,4, di-t-butylphenyl 3 ′, 5′-di-t-butyl-4′-hydroxybenzoate, nickel dibutyl-dithiocarbamate.
[0166]
The photosensitive layer 6 can contain at least one electron accepting substance for the purpose of improving sensitivity, reducing residual potential, reducing fatigue during repeated use, and the like.
[0167]
Usable electron accepting substances include, for example, succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m- Examples include dinitrobenzene, chloranil, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, and phthalic acid.
[0168]
Of these, fluorenone, quinone, -Cl, -CN, -NO ₂ A benzene derivative having an electron-withdrawing substituent such as is particularly preferably used. Furthermore, a small amount of silicone oil can be added to the coating solution for forming a photosensitive layer of the present invention as a leveling agent for improving the smoothness of the coating film.
[0169]
The electrophotographic photosensitive member of the present invention described above is an electrophotographic apparatus such as a laser beam printer, a digital copying machine, an LED printer, or a laser facsimile that emits near-infrared light or visible light, and such an electrophotographic apparatus. It can be mounted on a process cartridge provided in the apparatus. The electrophotographic photoreceptor of the present invention can be used in combination with a one-component or two-component regular developer or reversal developer. Further, even when the electrophotographic photosensitive member of the present invention is mounted on a contact charging type electrophotographic apparatus using a charging roller or a charging brush, good characteristics with little occurrence of current leakage can be obtained.
[0170]
Next, an electrophotographic apparatus and a process cartridge equipped with the electrophotographic photosensitive member of the present invention will be described.
[0171]
FIG. 9 is a cross-sectional view schematically showing a basic configuration of a preferred embodiment of the electrophotographic apparatus of the present invention. An electrophotographic apparatus 200 shown in FIG. 9 includes an electrophotographic photosensitive member 7, a charging means 8 such as a corotron or a scorotron for charging the electrophotographic photosensitive member 7 by a corona discharge method, a power source 9 connected to the charging means 8, An exposure unit 10 that exposes the electrophotographic photosensitive member 7 charged by the charging unit 8 to form an electrostatic latent image, and a toner image is formed by developing the electrostatic latent image formed by the exposure unit 10 with toner. The image forming apparatus includes a developing unit 11, a transfer unit 12 that transfers a toner image formed by the developing unit 11 to a transfer medium, a cleaning device 13, a static eliminator 14, and a fixing device 15.
[0172]
FIG. 10 is a cross-sectional view schematically showing a basic configuration of another embodiment of the electrophotographic apparatus of the present invention shown in FIG.
[0173]
An electrophotographic apparatus 210 shown in FIG. 10 has the same configuration as that of the electrophotographic apparatus 200 shown in FIG. 9 except that it includes a charging unit 8 that charges the electrophotographic photoreceptor 7 by a contact method. In particular, an electrophotographic apparatus that employs contact-type charging means in which an AC voltage is superimposed on a DC voltage can be preferably used because it has excellent wear resistance. In this case, the static eliminator 14 may not be provided.
[0174]
The charging means (charging member) 8 is disposed so as to be in contact with the surface of the photoconductor 7 and applies a voltage uniformly to the photoconductor to charge the surface of the photoconductor to a predetermined potential. The charging means 8 includes metals such as aluminum, iron and copper, conductive polymer materials such as polyacetylene, polypyrrole and polythiophene, polyurethane rubber, silicone rubber, epichlorohydrin rubber, ethylene propylene rubber, acrylic rubber, fluorine rubber and styrene-butadiene. A material obtained by dispersing metal oxide particles such as carbon black, copper iodide, silver iodide, zinc sulfide, silicon carbide, and metal oxide in an elastomer material such as rubber and butadiene rubber can be used.
[0175]
Examples of this metal oxide are ZnO and SnO. ₂ , TiO ₂ , In ₂ O _Three , MoO _Three Or a complex oxide thereof. Further, the charging means 8 may be made by adding perchlorate in an elastomer material and imparting conductivity.
[0176]
Further, the charging means 8 may be provided with a coating layer on the surface thereof. As a material for forming the coating layer, N-alkoxymethylated nylon, cellulose resin, vinyl pyridine resin, phenol resin, polyurethane, polyvinyl butyral, melamine and the like are used alone or in combination. Also, emulsion resin-based materials such as acrylic resin emulsion, polyester resin emulsion, polyurethane, particularly emulsion resin synthesized by soap-free emulsion polymerization can be used.
[0177]
In these resins, in order to further adjust the resistivity, conductive agent particles may be dispersed, or an antioxidant may be contained in order to prevent deterioration. In addition, in order to improve the film formability when forming the coating layer, the emulsion resin may contain a leveling agent or a surfactant. Examples of the shape of the contact charging member include a roller type, a blade type, a belt type, and a brush type.
[0178]
Furthermore, the electrical resistance value of the charging means 8 is preferably 10 ² ~Ten ¹⁴ Ωcm, more preferably 10 ² ~Ten ¹² The range of Ωcm is good. Further, as the voltage applied to the contact charging member, either direct current or alternating current can be used. It can also be applied in the form of direct current + alternating current.
[0179]
FIG. 11 is a sectional view schematically showing a basic configuration of still another embodiment of the electrophotographic apparatus of the present invention shown in FIG. An electrophotographic apparatus 220 shown in FIG. 11 is an intermediate transfer type electrophotographic apparatus, and four electrophotographic photosensitive members 401 a to 401 d are arranged in parallel with each other along an intermediate transfer belt 409 in a housing 400.
[0180]
Here, the electrophotographic photoreceptors 401a to 401d mounted on the electrophotographic apparatus 220 are respectively the electrophotographic photoreceptors of the present invention. For example, the above-described electrophotographic photoreceptor 100, electrophotographic photoreceptor 110, electrophotographic photoreceptor 120, electrophotographic photoreceptor 130, electrophotographic photoreceptor 140, electrophotographic photoreceptor 150, electrophotographic photoreceptor 160, electrophotographic Any of the photoreceptors 170 may be mounted.
[0181]
Each of the electrophotographic photoreceptors 1a to 401d can be rotated in a predetermined direction (counterclockwise on the paper surface), and the charging rolls 402a to 402d, the developing devices 404a to 404d, and the primary transfer roll 410a along the rotation direction. To 410d and cleaning blades 15a to 15d are arranged. Each of the developing devices 404a to 404d can be supplied with toners of four colors, black, yellow, magenta, and cyan accommodated in toner cartridges 405a to 405d, and the primary transfer rolls 410a to 410d are respectively intermediate transfer members. 9 is in contact with the electrophotographic photoreceptors 1a to 401d.
[0182]
Further, a laser light source (exposure means) 403 is disposed at a predetermined position in the housing 400, and the surface of the electrophotographic photoreceptors 1a to 401d after charging is irradiated with laser light emitted from the laser light source 403. Is possible. Thus, the charging, exposure, development, primary transfer, and cleaning processes are sequentially performed in the rotation process of the electrophotographic photoreceptors 1a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner.
[0183]
The intermediate transfer belt 409 is supported with a predetermined tension by a drive roll 406, a backup roll 408, and a tension roll 407, and can rotate without causing deflection due to the rotation of these rolls. Further, the secondary transfer roll 413 is disposed so as to contact the backup roll 408 with the intermediate transfer body 9 interposed therebetween. The intermediate transfer belt 409 passing between the backup roll 408 and the secondary transfer roll 413 is cleaned by the cleaning blade 14 and then repeatedly used in the next image forming process.
[0184]
Further, a tray (transfer medium tray) 411 is provided at a predetermined position in the housing 400, and a transfer medium such as paper in the tray 411 is transferred to the intermediate transfer belt 409 and the secondary transfer roll 413 by the transfer roll 412. Between the two fixing rolls 414 that are in contact with each other, and then discharged to the outside of the housing 400.
[0185]
FIG. 12 is a cross-sectional view schematically showing a basic configuration of a preferred embodiment of the process cartridge of the present invention. The process cartridge 300 combines the electrophotographic photosensitive member 7 with the charging unit 8, the developing unit 11, the cleaning device (cleaning unit) 13, the opening 18 for exposure, and the static eliminator 14 using the mounting rail 16, and It is an integrated one.
[0186]
The process cartridge 300 is detachable from the main body of the electrophotographic apparatus comprising the transfer means 12, the fixing device 15, and other components not shown, and the electrophotographic apparatus together with the main body of the electrophotographic apparatus. It constitutes.
[0187]
【Example】
Hereinafter, the content of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.
[0188]
The electrophotographic photoreceptors of Examples 1 to 4 and Comparative Examples 1 to 6 having the same configuration as the electrophotographic photoreceptor 100 shown in FIG.
[0189]
When producing the undercoat layer of each electrophotographic photosensitive member, the fluorescent X-ray analysis of the metal oxide particles A is performed under the following conditions using a fluorescent X-ray analyzer (trade name: System 3370E, manufactured by Rigaku Corporation). I went there. That is, the target of the X-ray source: Rh, the applied voltage to the X-ray source: 50 kV, the current value: 50 mA, and the spectroscopic crystal of the optical system has the type of detection element in the metal oxide particles A to be measured. LiF, TAP, PET, Ge were used accordingly. The detector used was a scintillation counter and a photo counter. Further, the scanning of the spectroscope was performed by using the skip scanning method, and the characteristic X-ray intensity was measured by setting an angle of 0.05 degrees per step.
[0190]
The specific surface area of the metal oxide particle B or the metal oxide particle A is measured using a flow type specific surface area automatic measuring apparatus Flowsorb II2300 (manufactured by Shimadzu Corporation), and 200 mg of the metal oxide particle to be measured is 200 mg. After degassing at 30 ° C. for 30 minutes, the specific surface area value was measured by the BET one-point method.
[0191]
Example 1
A photoconductor having the same configuration as that of the electrophotographic photoconductor 100 shown in FIG.
[0192]
Tin oxide (trade name: S1, made by Mitsubishi Materials, specific surface area: 50m ² / G): 100 parts by mass was mixed with 500 parts by mass of toluene, and 15 parts by mass of a silane coupling agent (trade name: A1100, manufactured by Nihon Unicar Co., Ltd.) was added and stirred for 5 hours. Then, toluene was distilled off under reduced pressure and baked at 100 ° C. for 2 hours.
[0193]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained tin oxide after the surface treatment, “characteristic X-ray intensity I1 / Sn characteristic X-ray intensity I2” was 2.0 × 10. ^-Four Met. The specific surface area of the tin oxide after the surface treatment is 60 m. ² / G.
[0194]
Next, tin oxide after surface treatment: 35 parts by mass, curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 15 parts by mass, butyral resin BM-1 (manufactured by Sekisui Chemical Co., Ltd.): 6 Mass parts and 44 parts by mass of methyl ethyl ketone were mixed, and dispersion was obtained by dispersing for 2 hours with a sand mill using glass beads of 1 mmφ.
[0195]
Dioctyltin dilaurate: 0.005 parts by mass and silicone oil SH29PA (manufactured by Toray Dow Corning Silicone): 0.01 parts by mass were added as catalysts to the resulting dispersion to obtain an undercoat layer coating solution. . This coating solution is applied on an aluminum substrate (conductive support layer) having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes and a thickness of 20 μm or less. A draw layer was formed.
[0196]
Next, a photosensitive layer having a two-layer structure was formed on the undercoat layer. First, X-ray diffraction spectrum Bragg angles (2θ ± 0.2 °) using Cukα as a charge generating substance are at least 7.4 °, 16.6 °, 25.5 °, and 28.3 °. A mixture comprising 15 parts by mass of gallium chloride phthalocyanine having a diffraction peak, 10 parts by mass of vinyl chloride / vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar) serving as a binder resin, and 300 parts by mass of n-butyl acetate. 1 mmφ glass beads were used for dispersion for 4 hours in a sand mill.
[0197]
The obtained dispersion was dip-coated on the undercoat layer as a coating solution for forming a charge generation layer and dried to form a charge generation layer having a layer thickness of 0.2 μm.
[0198]
Furthermore, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine: 4 parts by mass and bisphenol Z polycarbonate resin (viscosity average molecular weight) 40,000): 6 parts by mass and chlorobenzene: 80 parts by mass were dissolved. The obtained dispersion was dip-coated on the charge generation layer as a coating solution for forming a charge transport layer, and dried at 130 ° C. for 40 minutes to form a charge transport layer having a layer thickness of 25 μm.
[0199]
(Example 2)
A photoconductor having the same configuration as that of the electrophotographic photoconductor 100 shown in FIG.
[0200]
Titanium oxide (trade name: TAF500J, manufactured by Fuji Titanium, specific surface area: 18 m ² / G): While stirring 100 parts by mass in a mixer, a mixed solution of 10 parts by mass of toluene and a silane coupling agent (trade name: KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.): 2 parts by mass is added. Stir for minutes. Then, toluene was distilled off under reduced pressure and baked at 170 ° C. for 2 hours.
[0201]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained titanium oxide after the surface treatment, “characteristic X-ray intensity I1 / Ti characteristic X-ray intensity I2” is 2.0 × 10 ^-Four Met. The specific surface area of the tin oxide after the surface treatment is 20 m. ² / G.
[0202]
Next, titanium oxide after surface treatment: 50 parts by mass, curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 15 parts by mass, butyral resin BM-1 (manufactured by Sekisui Chemical Co., Ltd.): 6 Part by mass and 60 parts by mass of methyl ethyl ketone were mixed, and dispersion was obtained by dispersing for 4 hours with a sand mill using 1 mmφ glass beads.
[0203]
Dioctyltin dilaurate: 0.005 parts by mass and silicone oil SH29PA (manufactured by Toray Dow Corning Silicone): 0.01 parts by mass were added as catalysts to the resulting dispersion to obtain an undercoat layer coating solution. . This coating solution is applied on an aluminum substrate (conductive support layer) having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes and a thickness of 20 μm or less. A draw layer was formed.
[0204]
Next, a charge generation layer and a charge transport layer were sequentially formed in the same procedure as in Example 1 to produce an electrophotographic photoreceptor.
[0205]
Example 3
A photoconductor having the same configuration as that of the electrophotographic photoconductor 100 shown in FIG.
[0206]
Zinc oxide (average particle size 70 nm , Teica prototype, specific surface area: 15m ² / G): 100 parts by weight of toluene was mixed with 500 parts by weight of toluene, and a silane coupling agent (trade name: KBM603, manufactured by Shin-Etsu Chemical Co., Ltd.): 1.5 parts by weight was added thereto and stirred for 2 hours. Thereafter, toluene was distilled off under reduced pressure and baked at 150 ° C. for 2 hours.
[0207]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained zinc oxide after the surface treatment, “Si characteristic X-ray intensity I1 / Zn characteristic X-ray intensity I2” is 1.5 × 10. ^-Five Met. The specific surface area of the tin oxide after the surface treatment is 15 m. ² / G.
[0208]
Next, zinc oxide after the surface treatment: 60 parts by mass, curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 15 parts by mass, butyral resin BM-1 (manufactured by Sekisui Chemical Co., Ltd.): 15 Part by mass and 85 parts by mass of methyl ethyl ketone were mixed. The obtained liquid: 8 parts by mass and methyl ethyl ketone: 25 parts by mass were mixed and dispersed for 2 hours in a sand mill using 1 mmφ glass beads to obtain a dispersion.
[0209]
Dioctyltin dilaurate: 0.005 parts by mass and silicone oil SH29PA (manufactured by Toray Dow Corning Silicone): 0.01 parts by mass were added as catalysts to the resulting dispersion to obtain an undercoat layer coating solution. . This coating solution is applied on an aluminum substrate (conductive support layer) having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes and a thickness of 20 μm or less. A draw layer was formed.
[0210]
Next, a photosensitive layer having a two-layer structure was formed on the undercoat layer. First, X-ray diffraction spectrum Bragg angles (2θ ± 0.2 °) using Cukα as a charge generating material are at least 7.3 °, 16.0 °, 24.9 °, and 28.0 °. A mixture of 15 parts by mass of a hydroxygallium phthalocyanine having a diffraction peak at 10 parts by mass, 10 parts by mass of vinyl chloride / vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar) serving as a binder resin, and 300 parts by mass of n-butyl acetate. 1 mmφ glass beads were used for dispersion for 4 hours in a sand mill.
[0211]
The obtained dispersion was dip-coated on the undercoat layer as a coating solution for forming a charge generation layer and dried to form a charge generation layer having a layer thickness of 0.2 μm. Next, a charge transport layer was formed in the same procedure as in Example 1 to produce an electrophotographic photoreceptor.
[0212]
Example 4
A photoconductor having the same configuration as that of the electrophotographic photoconductor 100 shown in FIG.
[0213]
Zinc oxide (trade name: MZ300, manufactured by Teika, specific surface area: 40 m ² / G): 100 parts by mass was mixed with 500 parts by mass of toluene, and 5 parts by mass of a silane coupling agent (trade name: KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) was added thereto and stirred for 2 hours. Thereafter, toluene was distilled off under reduced pressure and baked at 150 ° C. for 2 hours.
[0214]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained zinc oxide after the surface treatment, “Si characteristic X-ray intensity I1 / Zn characteristic X-ray intensity I2” is 5.0 × 10. ^-Five Met. The specific surface area of the tin oxide after the surface treatment is 30 m. ² / G.
[0215]
Next, zinc oxide after the surface treatment: 60 parts by mass, curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 15 parts by mass, butyral resin BM-1 (manufactured by Sekisui Chemical Co., Ltd.): 15 Part by mass and 85 parts by mass of methyl ethyl ketone were mixed. The obtained liquid: 38 parts by mass and methyl ethyl ketone: 25 parts by mass were mixed and dispersed in a sand mill for 2 hours using 1 mmφ glass beads to obtain a dispersion.
[0216]
Dioctyltin dilaurate: 0.005 parts by mass and silicone oil SH29PA (manufactured by Toray Dow Corning Silicone): 0.01 parts by mass were added as catalysts to the resulting dispersion to obtain an undercoat layer coating solution. . This coating solution is applied on an aluminum substrate (conductive support layer) having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm by a dip coating method, followed by drying and curing at 160 ° C. for 100 minutes and a thickness of 20 μm or less. A draw layer was formed.
[0217]
Next, a photosensitive layer having a two-layer structure was formed on the undercoat layer. First, oxytitanyl phthalocyanine having a diffraction peak at a position where the Bragg angle (2θ ± 0.2 °) of an X-ray diffraction spectrum using Cukα rays as a charge generation material is at least 27.3 °: 15 parts by mass, binder resin A mixture of 10 parts by weight of vinyl chloride / vinyl acetate copolymer resin (VMCH, manufactured by Nippon Unicar Co., Ltd.) and 300 parts by weight of n-butyl acetate was dispersed in a sand mill for 4 hours using 1 mmφ glass beads. .
[0218]
The obtained dispersion was dip-coated on the undercoat layer as a coating solution for forming a charge generation layer and dried to form a charge generation layer having a layer thickness of 0.2 μm. Next, a charge transport layer was formed in the same procedure as in Example 1 to produce an electrophotographic photoreceptor.
[0219]
(Comparative Example 1)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the metal oxide fine particles used in Example 1 were used without being surface-treated.
[0220]
(Comparative Example 2)
An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that the metal oxide fine particles used in Example 2 were used without being surface-treated.
[0221]
(Comparative Example 3)
An electrophotographic photosensitive member was produced in the same manner as in Example 3 except that the metal oxide fine particles used in Example 3 were used without being surface-treated.
[0222]
(Comparative Example 4)
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the metal oxide fine particles used in Example 4 were used without being surface-treated.
[0223]
(Comparative Example 5)
An electrophotographic photosensitive member was produced in the same manner as in Example 3 except that the amount of the silane coupling agent (trade name: KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.) used in Example 3 was changed to 30 parts by mass.
[0224]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained zinc oxide after the surface treatment, “characteristic X-ray intensity I1 / Z characteristic X-ray intensity I2” is 2.0 × 10. ^-3 Met. The specific surface area of the tin oxide after the surface treatment is 15 m. ² / G.
[0225]
(Comparative Example 6)
An electrophotographic photosensitive member was produced in the same manner as in Example 4 except that the amount of the silane coupling agent (trade name: KBM503, manufactured by Shin-Etsu Chemical Co., Ltd.) used in Example 4 was changed to 0.05 parts by mass. did.
[0226]
As a result of performing the above-mentioned fluorescent X-ray analysis on the obtained zinc oxide after the surface treatment, “Si characteristic X-ray intensity I1 / Zn characteristic X-ray intensity I2” is 5.0 × 10. ^-8 Met. The specific surface area of the tin oxide after the surface treatment is 30 m. ² / G.
[0227]
[Electrophotographic characteristic evaluation test of electrophotographic photosensitive member]
(1) Initial characteristics evaluation (initial potential measurement)
The electrophotographic photosensitive members of Examples 1 to 4 and Comparative Examples 1 to 6 were applied to a laser printer-scanner (trade name: XP-15 modified machine, manufactured by Fuji Xerox Co., Ltd.) having the same structure as FIG. The electrophotographic characteristics of each electrophotographic photosensitive member were evaluated as follows.
[0228]
Measures the surface potential A [V] of each electrophotographic photosensitive member when the electrophotographic photosensitive member is charged with a scorotron charger with a grid applied voltage of −700 V in a normal temperature and normal humidity (20 ° C., 40% RH) environment. did. Next, 10 mJ / m is applied to each electrophotographic photosensitive member 1 second after being charged using a 780 nm semiconductor laser. ² The electric potential B [V] on the surface of each electrophotographic photosensitive member at this time was measured. Subsequently, after 3 seconds from the discharge, 50 mJ / m is applied to each electrophotographic photosensitive member. ² The red LED light was irradiated to remove static electricity, and the surface potential C [V] of each electrophotographic photosensitive member at this time was measured.
[0229]
Here, the higher the value of the potential A, the higher the acceptance potential of the electrophotographic photosensitive member, so that the contrast can be increased. Further, the lower the potential B, the higher the sensitivity of the electrophotographic photosensitive member. Further, the lower the value of the potential C, the smaller the residual potential, and it is evaluated as an electrophotographic photosensitive member with less image memory and so-called fogging. These results are shown in Table 1.
[0230]
(2) Characteristic evaluation after repeated use
The above operation was repeated 10,000 times, and the potentials A to C after charging and exposure were measured. These results are shown in Table 1.
[0231]
(3) Evaluation of stability against changes in usage environment
The above operation was performed in two different environments of low temperature and low humidity (10 ° C., 15% RH) and high temperature and high humidity (28 ° C., 85% RH), and the potentials A to C after charging and exposure were measured. . Then, the fluctuation amounts (ΔA, ΔB, ΔC) of the potentials A to C between these different environments were measured, and the stability of each electrophotographic photosensitive member was evaluated against changes in the usage environment. These results are shown in Table 1.
[0232]
(4) Image quality evaluation after printing 10,000 sheets
A full-color printer (trade name: Docu Print C620, Fuji Xerox) using the electrophotographic photosensitive members of Examples 1 to 4 and Comparative Examples 1 to 6 having the same structure as that of FIG. And a continuous print test on 10,000 sheets of paper.
[0233]
Then, the image quality after printing 10,000 sheets was “no abnormality”; good image quality was obtained, “overall fogging occurred”; fine black spots were observed on the entire paper surface, “black spot generation”; large black spots on the paper surface The evaluation was made based on the evaluation criteria. These results are shown in Table 1.
[0234]
[Table 1]

[0235]
【The invention's effect】
As described above, according to the method for producing an electrophotographic photosensitive member of the present invention, an electronic device capable of sufficiently preventing deterioration in electrical characteristics due to repeated use and obtaining high durability and high resolution quality. A photographic photoreceptor can be provided. By providing such an electrophotographic photosensitive member, it is possible to provide a process cartridge and an electrophotographic apparatus that can obtain high resolution quality even when used repeatedly over a long period of time.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of an electrophotographic photosensitive member of the present invention.
FIG. 2 is a cross-sectional view showing a second embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 3 is a cross-sectional view showing a third embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 4 is a cross-sectional view showing a fourth embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 5 is a cross-sectional view showing a fifth embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 6 is a cross-sectional view showing a sixth embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 7 is a cross-sectional view showing a seventh embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 8 is a sectional view showing an eighth embodiment of the electrophotographic photosensitive member of the present invention.
FIG. 9 is a cross-sectional view schematically showing a basic configuration of a preferred embodiment of the electrophotographic apparatus of the present invention.
10 is a cross-sectional view schematically showing a basic configuration of another embodiment of the electrophotographic apparatus of the present invention shown in FIG.
11 is a cross-sectional view schematically showing a basic configuration of still another embodiment of the electrophotographic apparatus of the present invention shown in FIG.
FIG. 12 is a cross-sectional view schematically showing a basic configuration of a preferred embodiment of the process cartridge of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Charge generating layer, 3 ... Conductive support layer, 4 ... Undercoat layer, 5 ... Protective layer, 6 ... Photosensitive layer, 7 ... Electrophotographic photosensitive member, 8 ... Charging means, 9 ... Power supply, 10 ... Exposure means 11 ... developing means, 12 ... transfer means, 13 ... cleaning device, 14 ... static discharger, 16 ... mounting rail, 18 ... opening for exposure, 42 ... intermediate layer, 100, 110, 120, 130, 140, 150, 160, 170 ... electrophotographic photosensitive member, 200 ... electrophotographic device, 210 ... electrophotographic device, 300 ... process cartridge, 400 ... housing, 401a-401d ... electrophotographic photosensitive member, 402a-402d.・ Charging roll, 403... Laser light source (exposure device), 404 a to 404 d... Development device, 405 a to 405 d. Tension roll, 408 ... Backup roll, 409 ... Intermediate transfer belt, 410a to 410d ... Primary transfer roll, 411 ... Tray (tray to be transferred), 412 ... Transfer roll, 413 .. Secondary transfer roll, 414... Fixing roll.

Claims (7)

A conductive support layer, a photosensitive layer containing a pigment, and an undercoat layer disposed between the conductive support layer and the photosensitive layer, and the undercoat layer includes A method for producing an electrophotographic photoreceptor containing zinc oxide particles surface-treated with an organometallic compound having a hydrolyzable functional group,
Forming the undercoat layer using the surface-treated zinc oxide particles satisfying the condition represented by the following formula (1):
A method for producing an electrophotographic photosensitive member characterized by the above.
1.0 × 10 ⁻⁶ ≦ (I1 / I2) ≦ 1.0 × 10 ⁻³ (1)
[In Formula (1),
I1 represents the characteristic X-ray intensity of the metal element constituting the organometallic compound obtained from the fluorescent X-ray analysis of the surface-treated zinc oxide particles;
I2 represents the characteristic X-ray intensity of zinc constituting the surface-treated zinc oxide particles. ]   The method for producing an electrophotographic photosensitive member according to claim 1, wherein the thickness of the undercoat layer is adjusted to 15 to 50 μm. An electrophotographic photoreceptor comprising a conductive support layer, a photosensitive layer containing a pigment, and an undercoat layer disposed between the conductive support layer and the photosensitive layer,
The undercoat layer contains zinc oxide particles surface-treated with an organometallic compound having a hydrolyzable functional group,
The surface-treated zinc oxide particles satisfy the condition represented by the following formula (1),
An electrophotographic photoreceptor characterized by the above.
1.0 × 10 ⁻⁶ ≦ (I1 / I2) ≦ 1.0 × 10 ⁻³ (1)
[In Formula (1),
I1 represents the characteristic X-ray intensity of the metal element constituting the organometallic compound obtained from the fluorescent X-ray analysis of the surface-treated zinc oxide particles;
I2 represents the characteristic X-ray intensity of zinc constituting the surface-treated zinc oxide particles. ]   The electrophotographic photosensitive member according to claim 3, wherein the undercoat layer has a thickness of 15 to 50 μm. The electrophotographic photosensitive member according to claim 3 or 4,
A process cartridge having at least one of a charging unit, a developing unit, a cleaning unit, and a charge eliminating unit, and is detachable from an electrophotographic apparatus body. The electrophotographic photosensitive member according to claim 3 or 4,
Charging means for charging the electrophotographic photoreceptor;
Exposure means for exposing the electrophotographic photosensitive member charged by the charging means to form an electrostatic latent image; and
Developing means for developing the electrostatic latent image with toner to form a toner image;
Transfer means for transferring the toner image to a transfer medium;
An electrophotographic apparatus comprising:   The transfer method of the transfer means is an intermediate transfer method in which the toner image is primarily transferred to an intermediate transfer member, and the primary transfer image on the intermediate transfer member is secondarily transferred to the transfer medium. The electrophotographic apparatus according to claim 6.

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