JP4482964B2 - Electrophotographic photoreceptor - Google Patents

Description

【００１１】
〔式中、Ｘは水素原子、ハロゲン原子、アルキル基、シクロアルキル基、アルコキシ基またはアルキルアリール基を表し、Ｒ1はアルキル基、シクロアルキル基、アリール基、アルコキシ基またはアラルキル基を表し、Ｒ2は水素原子、アルキル基またはアリール基を表す、Ｒ3およびＲ4は同一でも異なってもよく、それぞれアルキル基、シクロアルキル基、アリール基またはアルキルアリール基を表す〕で表されるベンゾトリアゾール−アルキレンビスフェノール化合物の１種または２種以上と、分子中にアリールアミノ基を有する電荷輸送剤の１種または２種以上を含有する感光層を有することを特徴とする電子写真用感光体である。
【００１２】
また、本発明は分子中にアリールアミノ基を有する電荷輸送剤が下記一般式［２］、［３］または［４］
【００１３】
【化９】

【００１４】
【化１０】

【００１５】
【化１１】

【００１６】
〔式［２］、式［３］、式［４］において、Ｚは２価基−Ｏ−、−Ｓ−または−Ｎ（Ｒ10）−を表す。Ｒ5およびＲ6は同一でも異なってもよく、それぞれ無置換もしくは置換基を有する炭素原子数１ないし１２の直鎖状もしくは分岐状のアルキル基、無置換もしくは置換基を有する炭素原子数７ないし２０の直鎖状もしくは分岐状のアラルキル基、または無置換もしくは置換基を有する環数１ないし４のアリール基を表す。Ｒ7、Ｒ8、Ｒ9およびＲ11はそれぞれ水素原子、無置換もしくは置換基を有する炭素原子数１ないし１２の直鎖状もしくは分岐状のアルキル基、無置換もしくは置換基を有する炭素原子数７ないし２０の直鎖状もしくは分岐状のアラルキル基、炭素原子数１ないし４の直鎖状もしくは分岐状のアルコキシ基、アリールオキシ基、アシル基、炭素原子数２ないし５のアルコキシカルボニル基、ハロゲン原子、ニトロ基、炭素原子数１ないし４のアルキル基で置換されたモノアルキル基、炭素原子数１ないし４のアルキル基で置換されたジアルキルアミノ基、またはアミド基を表す。Ｒ10は無置換もしくは置換基を有する炭素原子数１ないし１２の直鎖状もしくは分岐状のアルキル基、または無置換もしくは置換基を有する炭素原子数１ないし１２の直鎖状もしくは分岐状のアラルキル基を表す。Ｒ5ないしＲ11が置換基を有する場合、置換基としてはハロゲン原子、アルコキシ基、アリールオキシ基、ジアルキルアミノ基またはアルキルチオ基を表し、Ｒ5またはＲ6がアリール基の場合のみ、さらにアルキル基をも表す。〕で表されるヒ
ドラゾン化合物であり、該ヒドラゾン化合物の１種または２種以上を含有する感光層を有することを特徴とする電子写真用感光体である。
【００１７】
また本発明は分子中にアリールアミノ基を有する電荷輸送剤が下記一般式［５］
【００１８】
【化１２】

【００１９】
〔式［５］においてＲ12は、水素原子、アルキル基、アルコキシ基、ハロゲン原子または置換アミノ基を表す。ｍは１または２の整数であり、ｍ＝２の場合、双方の基は同一でも異なってもよく、また双方の基は互いに結合してテトラメチレン環またはトリメチレン環を形成してもよい。Ｒ13は無置換または置換基を有するフェニル基を表し、この場合の置換基としてアルキル基、アルコキシ基、ハロゲン原子、水酸基、フェニル基が挙げられる。Ｒ14は水素、ハロゲン原子、アルキル基、アルコキシ基またはアルキルアミノ基を表す。Ｒ15およびＲ16は同一でも異なってもよく、それぞれ無置換もしくは置換基を有するフェニル基、無置換もしくは置換基を有するナフチル基、無置換もしくは置換基を有するアントリル基、無置換もしくは置換基を有するフルオレニル基または無置換もしくは置換基を有する複素環基を表し、この場合の置換基としてアルキル基、アルコキシ基、ハロゲン原子、水酸基、フェニル基が挙げられる。〕で表されるスチリル化合物であり、該スチリル化合物の１種または２種以上を含有する感光層を有することを特徴とする電子写真用感光体である。
【００２０】
また本発明は分子中にアリールアミノ基を有する電荷輸送剤が下記一般式［６］
【００２１】
【化１３】

【００２２】
〔式［６］においてＲ17は、水素原子、アルキル基、アルコキシ基またはハロゲン原子を表し、Ｒ18、Ｒ'18、Ｒ19およびＲ'19は同一でも異なってもよく、それぞれ水素原子、アルキル基、アルコキシ基、ハロゲン原子または置換アミノ基を表す。ｎは１または２の整数であり、ｎ＝２の場合、同一のフェニル基に置換される二つの基は同一でも異なってもよい。ｐは１または２の整数であり、ｐ＝２の場合、同一のフェニル基に置換される二つの基は同一でも異なってもよい。〕で表されるベンジジン化合物であり、該ベンジジン化合物の１種または２種以上を含有する感光層を有することを特徴とする電子写真用感光体である。
【００２３】
また本発明はベンゾトリアゾール−アルキレンビスフェノール化合物が下記一般式［７］
【００２４】
【化１４】

【００２５】
前記した一般式［１］で示されるベンゾトリアゾール−アルキレンビスフェノール化合物の具体例を示す。本発明に使用される化合物は、これらの化合物に限定されるものではない。
【００２６】
【化１５】

【００２７】
【化１６】

【００２８】
【化１７】

【００２９】
【化１８】

【００３０】
【化１９】

【００３１】
【化２０】

【００３２】
【化２１】

【００３３】
【化２２】

【００３６】
【化２５】

【００３７】
【化２６】

【００３８】
本発明の電子写真用感光体は、分子中にアリールアミノ基を有する電荷輸送剤の１種または２種以上を含有した感光層を有するものであり、さらに前記のベンゾトリアゾール−アルキレンビスフェノール化合物を１種または２種以上含有するものである。本発明で使用するベンゾトリアゾール−アルキレンビスフェノール化合物は感光体作製時の高温での乾燥によってもその拡散が抑制され、また、分子中にアリールアミノ基を有する電荷輸送剤に対する光劣化抑制と酸化防止効果が顕著なので、初期添加時の増し仕込みを要することが無く、添加剤増量に起因する感光体の物性低下特に表面抵抗の低下を防止することができるのである。また、分子中にアリールアミノ基を有する電荷輸送剤に作用して確実に光劣化の抑制と酸化防止を成し遂げるので、感光体の画像の低下や短寿命化を防止できるものである。
【００３９】
【発明の実施の形態】
感光層の形態としては種々のものが存在するが、本発明の電子写真用感光体の感光層としてはそのいずれも採用することができる。代表例として図１〜図５にそれらの感光体を示した。
【００４０】
図１の感光体は、導電性支持体１上に、分子中にアリールアミノ基を有する電荷輸送剤−これらは一般式［２］、［３］、［４］、［５］、［６］で表される特定のアミン化合物であっても良い、増感色素およびベンゾトリアゾール−アルキレンビスフェノール化合物、よりなる感光層２を設けたものである。
【００４１】
図２の感光体は、導電性支持体１上に分子中にアリールアミノ基を有する電荷輸送剤−これらは一般式［２］、［３］、［４］、［５］、［６］で表される特定のアミン化合物であっても良い、およびベンゾトリアゾール−アルキレンビスフェノール化合物よりなる電荷輸送媒体３の中に、電荷発生剤４を分散せしめた感光層２１を設けたものである。本感光体では電荷発生剤が光を吸収することにより電荷担体を発生し、これを電荷輸送媒体が輸送する。この場合、電荷輸送剤は電荷担体を発生させる光に対して透明であることが望ましい。アミン化合物は可視部波長域にほとんど吸収がないので、電荷発生剤と吸収波長域が重ならないという条件を満足している。
【００４２】
図３の感光体は、導電性支持体１上に電荷発生剤４を主体とする電荷発生層５と、アリールアミノ基を有する電荷輸送剤−これらは一般式［２］、［３］、［４］、［５］、［６］で表される特定のアミン化合物であっても良い、およびベンゾトリアゾール−アルキレンビスフェノール化合物よりなる電荷輸送層３の積層からなる感光層２２を設けたものである。本感光体では電荷輸送層３を透過した光が電荷発生層５に到達し、電荷発生剤４に吸収され電荷担体が発生される。この電荷担体は電荷輸送層３に注入され輸送される。
【００４３】
図４の感光体は、図３の感光体の電荷発生層５と電荷輸送層３の積層順を逆にした感光層２３を設けたものである。上記と同様の機構によって電荷担体の発生と輸送が説明できる。
【００４４】
図５の感光体は、機械的強度の向上を目的として図４の感光体の電荷発生層５の上に保護層６を更に積層した感光層２４を設けたものである。
【００４５】
本発明の感光体は次のようにして常法に従って製造することができる。例えば、前述した一般式［１］で表されるベンゾトリアゾール−アルキレンビスフェノール化合物と一般式［２］、［３］、［４］、［５］、［６］で表される特定のアミン化合物とを結着樹脂とともに適当な溶剤中に溶解し、必要に応じて電荷発生物質、増感色素、電子吸引性化合物あるいは、可塑剤、顔料、その他添加剤を添加して塗布液を調製する。この塗布液を導電性支持体上に塗布、乾燥して数μｍから数十μｍの感光層を形成させることにより、感光体を製造することができる。電荷発生層と電荷輸送層の二層よりなる感光層の場合は、電荷発生層の上に上記塗布液を塗布するか、上記塗布液を塗布して得られる電荷輸送層の上に電荷発生層を形成させることにより製造することができる。また、このようにして製造される感光体には必要に応じて、下引き層、中間層、バリヤー層を設けても良い。
【００４６】
前記した塗布液調製用の溶剤としては、テトラヒドロフラン、１，４−ジオキサン、メチルエチルケトン、シクロヘキサノン、アセトニトリル、Ｎ，Ｎ−ジメチルホルムアミド、酢酸エチル等の極性有機溶剤、トルエン、キシレン等の芳香族有機溶剤、ジクロロメタン、１，２−ジクロロエタン等の塩素系炭化水素溶剤等を使用することができる。アミン化合物と結着樹脂に対して溶解性の高い溶剤が好適に使用される。
【００４７】
結着樹脂としては、スチレン、酢酸ビニル、塩化ビニル、アクリル酸エステル、メタクリル酸エステルブタジエン等のビニル化合物の重合体および共重合体、ポリビニルアセタール、ポリカーボネート、ポリエステル、ポリフェニレンオキサイド、ポリウレタンセルロースエステル、フェノキシ樹脂、ケイ素樹脂、エポキシ樹脂等、ベンゾトリアゾール−アルキレンビスフェノール化合物および特定のアミン化合物と相溶性のある各種樹脂があげられる。また、結着樹脂の使用量は、通常アミン化合物に対して０．４〜１０重量倍、好ましくは０．５〜５重量倍の範囲である。
【００４８】
分子中にアリールアミノ基を有する電荷輸送剤−これらは一般式［２］、［３］、［４］、［５］、［６］で表される特定のアミン化合物であっても良い、に対して、一般式［１］で表されるベンゾトリアゾール−アルキレンビスフェノール化合物の１種または２種以上を、１〜４０重量％、好ましくは３〜３０重量％添加するのが効果的である。
【００４９】
電荷発生剤としては、α型、β型、τ型、Ｘ型等の各種結晶型のメタルフリーフタロシアニン、銅フタロシアニン、アルミニウムフタロシアニン、亜鉛フタロシアニン、α型、β型、Ｙ型オキソチタニルフタロシアニン、コバルトフタロシアニン、ヒドロキシガリウムフタロシアニン、クロルアルミニウムフタロシアニン、クロルインジウムフタロシアニン、Ｃｕ−Ｋα線（波長１．５４１ ）に対するブラック角２θの９．６°および２７．２°に大きなピークを有するチタニルフタロシアニン等のフタロシアニン系顔料。トリフェニルアミン骨格を有するアゾ顔料、ジフェニルアミン骨格を有するアゾ顔料、カルバゾール骨格を有するアゾ顔料、フルオレン骨格を有するアゾ顔料、オキサジアゾール骨格を有するアゾ顔料、ビススチルベン骨格を有するアゾ顔料、ジベンゾチオフェン骨格を有するアゾ顔料、スチルベン骨格を有するアゾ顔料、ジスチリルベンゼン骨格を有するアゾ顔料、カルバゾール骨格を有するトリスアゾ顔料等のアゾ系顔料。ペリレン酸無水物、ペリレン酸イミド等のペリレン顔料。アントラキノン誘導体、アンスアンスロン誘導体、ジベンズピレンキノン誘導体、ピラントロン誘導体、ビオラントロン誘導体およびイソビオラントロン誘導体等の多環キノン顔料。ジフェニルメタンおよびトリフェニルメタン系顔料。シアニンおよびアゾメチン系顔料。インジゴイド系顔料、ビスベンズイミダゾール系顔料、アズレニウム塩、ピリリウム塩、チアピリリウム塩、ベンゾピリリウム塩、スクエアリリウム塩などがある。これらは、単独または必要に応じて２種以上混合して用いてもよい。
【００５０】
増感色素としては、メチルバイオレット、ブリリアントグリーン、クリスタルバイオレット、アシッドバイオレットのようなトリアリールメタン染料、ローダミンＢ、エオシンＳ、ローズベンガルのようなキサンテン染料、メチレンブルーのようなチアジン染料、ベンゾピリリウム塩のようなピリリウム染料やチアピリリウム染料、またはシアニン染料等が使用できる。
【００５１】
また、アミン化合物と電荷移動錯体を形成する電子吸引性化合物としては、クロラニル、２，３−ジクロロ−１，４−ナフトキノン、１−ニトロアントラキノン、２−クロロアントラキノン、フェナントレンキノン等のキノン類、４−ニトロベンズアルデヒド等のアルデヒド類、９−ベンゾイルアントラセン、インダンジオン、３，５−ジニトロベンゾフェノン、２，４，７−トリニトロフルオレノン、２，４，５，７−テトラニトロフルオレノン等のケトン類、無水フタル酸、４−クロロナフタル酸無水物等の酸無水物、テトラシアノエチレン、テレフタラルマレノニトリル、９−アントリルメチリデンマレノニトリル等のシアノ化合物、３−ベンザルフタリド、３−（α−シアノ−ｐ−ニトロベンザル）−４，５，６，７−テトラクロロフタリド等のフタリド類があげられる。
【００５２】
また、本発明の感光層には成膜性、可とう性、機械的強度を向上させる目的で周知の可塑剤を含有させても良い。可塑剤としては、例えばフタル酸エステル、リン酸エステル、塩素化パラフィン、メチルナフタリン、エポキシ化合物、塩素化脂肪酸エステル等を使用することができる。
【００５３】
本発明の感光層が形成される導電性支持体として、周知の電子写真用感光体に使用されている材料が使用できる。アルミニウム、ステンレス、銅等の金属ドラム、シートあるいはこれらの金属のラミネート物、蒸着物、また金属粉末、カーボンブラック、よう化銅、高分子電解質の導電性物質を適当なバインダーとともに塗布して導電処理したプラスチックフィルム、プラスチックドラム、紙、紙管、あるいは導電性物質を含有させることにより導電性を付与したプラスチックフィルムやプラスチックドラム等を使用することができる。
【００５４】
【実施例】
以下、実施例により本発明を具体的に説明する。実施例中の部は重量部を表わし、濃度は％を表す。
【００５５】
［実施例１］
電荷発生剤としてＸ型メタルフリーフタロシアニン（電荷発生剤Ｎｏ．１）
【００５６】
【化２７】

【００５７】
１．５部をポリビニルブチラール樹脂（エスレックＢＬ−Ｓ、積水化学工業（株）製）の３％シクロヘキサノン溶液５０部に加え、超音波分散機で１時間分散した。得られた分散液を導電性支持体であるアルミ蒸着ＰＥＴフィルムのアルミ面上にワイヤーバーを用いて塗布し、常圧下１１０℃で１時間乾燥して膜厚０．４μｍの電荷発生層を形成した。一方、添加剤として下記ベンゾトリアゾール−アルキレンビスフェノール化合物（添加剤Ｎｏ．１）１６部
【００５８】
【化２８】

【００５９】
および電荷輸送剤として下記ヒドラゾン化合物（電荷輸送剤Ｎｏ．１）
【００６０】
【化２９】

【００６１】
１４４部をポリカーボネート樹脂（ユーピロンＺ、三菱エンジニアリングプラスチック（株）製）の９．０％１，２−ジクロロエタン溶液２０００部に加え超音波をかけてベンゾトリアゾール−アルキレンビスフェノール化合物およびヒドラゾン化合物を完全に溶解させた。この溶液を前記の電荷発生層上にワイヤーバーで塗布し、常圧下１２０℃で１時間乾燥して膜厚２０μｍの電荷輸送層を形成せしめて、感光体を作製した。
【００６２】
［実施例２］
実施例１において電荷輸送剤Ｎｏ．１を用いる代わりに下記ヒドラゾン化合物（電荷輸送剤Ｎｏ．２）
【００６３】
【化３０】

【００６４】
を用いる以外は実施例１と同様にして感光体を作製した。
【００６５】
［実施例３］
実施例１において電荷輸送剤Ｎｏ．１を用いる代わりに下記ベンジジン化合物（電荷輸送剤Ｎｏ．３）
【００６６】
【化３１】

【００６７】
を用いる以外は実施例１と同様にして感光体を作製した。
【００６８】
［実施例４］
実施例１において電荷輸送剤Ｎｏ．１を用いる代わりに下記ベンジジン化合物（電荷輸送剤Ｎｏ．４）
【００６９】
【化３２】

【００７０】
を用いる以外は実施例１と同様にして感光体を作製した。
【００７１】
［比較例１］
実施例２において添加剤Ｎｏ．１を用いる代わりに下記ベンゾトリアゾール化合物（添加剤Ｎｏ．２）
【００７２】
【化３３】

【００７３】
と下記フェノール化合物（添加剤Ｎｏ．３）
【００７４】
【化３４】

【００７５】
の１：１重量比の混合物を用いる以外は実施例２と同様にして比較用感光体を作製した。
［実施例５］
実施例２において電荷発生剤Ｎｏ．１を用いる代わりにτ型メタルフリーフタロシアニン（電荷発生剤Ｎｏ．２）を用いる以外は実施例２と同様にして感光体を作製した。
【００７６】
［実施例６］
実施例５において電荷輸送剤Ｎｏ．２を用いる代わりに下記スチリル化合物（電荷輸送剤Ｎｏ．５）
【００７７】
【化３５】

【００７８】
と下記スチリル化合物（電荷輸送剤Ｎｏ．６）
【００７９】
【化３６】

【００８０】
の１：１重量比の混合物を用いる以外は実施例５と同様にして感光体を作製した。
【００８１】
［実施例７］
実施例５において電荷輸送剤Ｎｏ．２を用いる代わりにベンジジン化合物（電荷輸送剤Ｎｏ．４）を用いる以外は実施例５と同様にして感光体を作製した。
【００８２】
［実施例８］
実施例５において電荷輸送剤Ｎｏ．２を用いる代わりに下記ベンジジン化合物（電荷輸送剤Ｎｏ．７）
【００８３】
【化３７】

【００８４】
を用いる以外は実施例５と同様にして感光体を作製した。
【００８５】
［比較例２］
実施例６において添加剤Ｎｏ．１を用いる代わりにベンゾトリアゾール化合物（添加剤Ｎｏ．２）とフェノール化合物（添加剤Ｎｏ．３）の１：１重量比の混合物を用いる以外は実施例６と同様にして比較用感光体を作製した。
【００８６】
［実施例９］
実施例２において電荷発生剤Ｎｏ．１を用いる代わりに下記Ｙ型オキソチタニルフタロシアニン（電荷発生剤Ｎｏ．３）
【００８７】
【化３８】

【００８８】
を用いる以外は実施例２と同様にして感光体を作製した。
【００８９】
［実施例１０］
実施例６において電荷発生剤Ｎｏ．２を用いる代わりにα型オキソチタニルフタロシアニン（電荷発生剤Ｎｏ．４）を用いる以外は実施例６と同様にして感光体を作製した。
【００９０】
［比較例３］
実施例１０において添加剤Ｎｏ．１を用いる代わりにベンゾトリアゾール化合物（添加剤Ｎｏ．２）とフェノール化合物（添加剤Ｎｏ．３）の１：１重量比の混合物を用いる以外は実施例１０と同様にして比較用感光体を作製した。
【００９１】
［実施例１〜１０、比較例１〜３］
実施例１〜１０および比較例１〜３で作製した感光体を感光ドラム特性測定装置（商品名「ＥＬＹＳＩＡ−II」トレック・ジャパン（株）製）を用いて電子写真特性評価を行った。まず、感光体を暗所で−５．０ｋＶのコロナ放電を行い、続いて５０ｌｕｘのイレースランプを点灯したときの帯電電位Ｖ０を測定した。次いで７８０ｎｍ−４０μＷの単色光で露光し、残留電位Ｖｒを求めた。次に、この感光体を蛍光灯照明下の室内で２０ｐｐｍのオゾンガス中に５日間暴露した後、暴露前と同様にして、帯電電位Ｖ０と残留電位Ｖｒを測定した。結果を［表１］に示す。
【００９２】
【表１】

【００９３】
［実施例１１］
電荷発生剤として下記ビスアゾ顔料（電荷発生剤Ｎｏ．５）
【００９４】
【化３９】

【００９５】
１．０部およびポリエステル樹脂（バイロン２００、東洋紡（株）製）の５％テトラヒドロフラン溶液８．６部をテトラヒドロフラン８３部に加え、メノウ球入りのメノウポットに入れ、遊星型微粒粉砕機（フリッチュ社製）で１時間回転し、分散した。得られた分散液を導電性支持体であるアルミ蒸着ＰＥＴフィルムのアルミ面上にワイヤーバーを用いて塗布し、常圧下６０℃で２時間乾燥して膜厚０．３μｍの電荷発生層を形成した。一方、添加剤としてベンゾトリアゾール−アルキレンビスフェノール化合物（添加剤Ｎｏ．１）１６部と電荷輸送剤としてヒドラゾン化合物（電荷輸送剤Ｎｏ．１）１４４部をポリカーボネート樹脂（ユーピロンＺ、三菱エンジニアリングプラスチック（株）製）の９．０％１，２−ジクロロエタン溶液２０００部に加え超音波をかけてベンゾトリアゾール−アルキレンビスフェノール化合物およびヒドラゾン化合物を完全に溶解させた。この溶液を前記の電荷発生層上にワイヤーバーで塗布し、常圧下１２０℃で１時間乾燥して膜厚２０μｍの電荷輸送層を形成せしめて、感光体を作製した。
【００９６】
［実施例１２］
実施例１１において電荷輸送剤Ｎｏ．１を用いる代わりにスチリル化合物（電荷輸送剤Ｎｏ．６）を用いる以外は実施例１１と同様にして感光体を作製した。
【００９７】
［実施例１３］
実施例１１において電荷輸送剤Ｎｏ．１を用いる代わりにスチリル化合物（電荷輸送剤Ｎｏ．５）とスチリル化合物（電荷輸送剤Ｎｏ．６）の１：１重量比の混合物を用いる以外は実施例１１と同様にして感光体を作製した。
【００９８】
［比較例４］
実施例１２において添加剤Ｎｏ．１を用いる代わりにベンゾトリアゾール化合物（添加剤Ｎｏ．２）とフェノール化合物（添加剤Ｎｏ．３）の１：１重量比の混合物を用いる以外は実施例１２と同様にして比較用感光体を作製した。
【００９９】
［実施例１４］
電荷発生剤として下記トリスアゾ顔料（電荷発生剤Ｎｏ．６）
【０１００】
【化４０】

【０１０１】
１．０部およびポリビニルブチラール樹脂（エスレックＢＬ−Ｓ、積水化学工業（株）製）の５％テトラヒドロフラン溶液８．６部をテトラヒドロフラン８３部に加え、メノウ球入りのメノウポットに入れ、遊星型微粒粉砕機（フリッチュ社製）で１時間回転し、分散した。得られた分散液を導電性支持体であるアルミ蒸着ＰＥＴフィルムのアルミ面上にワイヤーバーを用いて塗布し、常圧下６０℃で２時間乾燥して膜厚０．３μｍの電荷発生層を形成した。一方、添加剤として下記ベンゾトリアゾール−アルキレンビスフェノール化合物（添加剤Ｎｏ．４）
【０１０２】
【化４１】

【０１０３】
１６部と電荷輸送剤として下記スチリル化合物（電荷輸送剤Ｎｏ．８）
【０１０４】
【化４２】

【０１０５】
１４４部をポリカーボネート樹脂（ユーピロンＺ、三菱エンジニアリングプラスチック（株）製）の９．０％１，２−ジクロロエタン溶液２０００部に加え超音波をかけてベンゾトリアゾール−アルキレンビスフェノール化合物およびスチリル化合物を完全に溶解させた。この溶液を前記の電荷発生層上にワイヤーバーで塗布し、常圧下１２０℃で１時間乾燥して膜厚２０μｍの電荷輸送層を形成せしめて、感光体を作製した。
【０１０６】
［実施例１５］
実施例１４において電荷輸送剤Ｎｏ．８を用いる代わりに下記ベンジジン化合物（電荷輸送剤Ｎｏ．９）
【０１０７】
【化４３】

【０１０８】
を用いる以外は実施例１４と同様にして感光体を作製した。
【０１０９】
［比較例５］
実施例１５において添加剤Ｎｏ．４を用いる代わりにベンゾトリアゾール化合物（添加剤Ｎｏ．２）とフェノール化合物（添加剤Ｎｏ．３）の１：１重量比の混合物を用いる以外は実施例１５と同様にして比較用感光体を作製した。
【０１１０】
［実施例１１〜１５、比較例４、５］
実施例１１〜１５および比較例４、５で作製した感光体を感光ドラム特性測定装置（商品名「ＥＬＹＳＩＡ−II」トレック・ジャパン（株）製）を用いて電子写真特性評価を行った。まず、感光体を暗所で−５．０ｋＶのコロナ放電を行い、続いて５０ｌｕｘのイレースランプを点灯したときの帯電電位Ｖ０を測定した。次いでイメージ露光７０ｌｕｘで露光し、残留電位Ｖｒを求めた。次に、この感光体を蛍光灯照明下の室内で２０ｐｐｍのオゾンガス中に５日間暴露した後、暴露前と同様にして、帯電電位Ｖ０と残留電位Ｖｒを測定した。結果を［表２］に示す。
【０１１１】
【表２】

【０１１２】
［表１］［表２］の結果から明白なように、添加剤に本発明のベンゾトリアゾール−アルキレンビスフェノール化合物を使用した実施例では、オゾンガス暴露後も感光体の帯電電位Ｖ０の低下が抑制されており、感光体の残留電位（Ｖｒ）の上昇も抑制されていることがわかる。一方、比較例ではオゾンガス暴露後に感光体の帯電電位Ｖ０が低下しており、感光体の残留電位（Ｖｒ）も上昇していることがわかる。
【０１１３】
【発明の効果】
本発明の分子中にアリールアミノ基を有する電荷輸送剤を使用し、ベンゾトリアゾール−アルキレンビスフェノール化合物を添加した電子写真用感光体は、オゾンガス暴露後も帯電電位の低下が防止され、残留電位の上昇が抑制される。さらに添加物の添加量が少なくて済むので、電子写真の基本性能をそこなうことなく、繰り返し安定性にも優れた性質を示す。
【図面の簡単な説明】
【図１】電子写真用単層感光体の断面図である。
【図２】電荷発生物質を分散させた電子写真用単層感光体の断面図である。
【図３】導電性支持体上に、電荷発生層、電荷輸送層の順に積層した電子写真用感光体の断面図である。
【図４】導電性支持体上に電荷輸送層、電荷発生層の順に積層した電子写真用感光体の断面図である。
【図５】保護層を設けた電子写真用感光体の断面図である。
【符号の説明】
１ 導電性支持体
２、２１、２２、２３、２４ 感光層
３ 電荷輸送媒体、電荷輸送層
４ 電荷発生物質
５ 電荷発生層
６ 保護層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic photoreceptor. Specifically, the present invention relates to an electrophotographic photoreceptor excellent in stability and durability excellent in ozone resistance and light resistance.
[0002]
[Prior art]
Conventionally, inorganic photoconductive materials such as selenium, zinc oxide, cadmium sulfide, and silicon have been widely used for electrophotographic photoreceptors. These inorganic materials have many advantages and at the same time have various drawbacks. For example, selenium is difficult to produce and has the disadvantages of being easily crystallized by heat and mechanical shock.Zinc oxide and cadmium sulfide have problems with moisture resistance and mechanical strength, and are charged by a dye added as a sensitizer. In addition, there is a drawback that the exposure deteriorates and the durability is insufficient. The conditions for producing silicon are difficult, and because of the use of highly irritating gas, the cost is high, and it is sensitive to humidity. In addition, selenium and cadmium sulfide have toxicity problems.
[0003]
In recent years, organic photoreceptors using various organic compounds have been studied and used widely in order to overcome the disadvantages of these inorganic photoreceptors. Organic photoreceptors include a single-layer photoreceptor in which a charge generator and a charge transport agent are dispersed in a binder resin, and a laminated photoreceptor in which functions are separated into a charge generation layer and a charge transport layer. The feature of such photoconductors, which are called function-separated types, is that a material suitable for each function can be selected from a wide range, and a photoconductor having an arbitrary performance can be easily produced. Has been promoted.
[0004]
As described above, various improvements such as the development of new materials and combinations thereof have been made in order to satisfy the basic performance and high durability requirements for electrophotographic photoreceptors. However, the current situation is that there is not enough.
[0005]
One major problem is that when a photoconductor is used in a copying machine, it undergoes a strong oxidizing action due to heat, light, ozone, etc. generated in the electrophotographic process. Photoreceptors made of organic materials are susceptible to this oxidizing action, for example, a decrease in sensitivity, a decrease in charging potential, an increase in residual potential, a decrease in surface resistance, etc., resulting in a significant decrease in image and a short life of the photoconductor. Has occurred.
[0006]
As a countermeasure, many studies have been made to prevent deterioration by adding stabilizers such as antioxidants and UV absorbers to the photoconductor. The additive was volatilized and the function was not fully exhibited. As measures against this, improvements were made to increase the molecular weight by adding bulky side chains to stabilizers such as antioxidants and UV absorbers, but the functional structure part that demonstrates performance only by measures against high molecular weight However, if the added amount is further increased, there arises a new problem that the wear resistance of the photoreceptor is lowered. On the other hand, a benzotriazole-alkylene bisphenol compound having the functions of a light stabilizer and an antioxidant is disclosed (Japanese Patent Laid-Open No. 10-175963), and the compound is added to various resins to test the light stabilization effect. As a result of the heat resistance test, it was reported that discoloration and coloring of those resins were prevented. However, there is no description of application examples in fields other than resins, such as the field of electrophotographic photoreceptors, and there is no specific description of addition to compounds such as low molecular charge transport agents.
[0007]
[Problems to be solved by the invention]
In the electrophotographic photoreceptor, the present inventors examined whether or not a benzotriazole-alkylene bisphenol compound can be added to the photoreceptor, the prevention of photodegradation and oxidative degradation of various charge transport agents, and the like. It has been found that it exhibits significant stabilization for charge transport agents having amino groups.
[0008]
In the present invention, when a charge transporting agent having an arylamino group in the molecule is used in an electrophotographic photoreceptor, the charging potential is prevented from being lowered, the residual potential is prevented from rising, and the repeated stability is further improved. Another object of the present invention is to provide an excellent electrophotographic photoreceptor.
[0009]
[Means for Solving the Problems]
The present invention provides the following general formula [1] on a conductive support.
[0010]
[Chemical 8]

[0011]
[Wherein, X represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or an alkylaryl group, R1 represents an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or an aralkyl group, and R2 represents A hydrogen atom, an alkyl group or an aryl group, and R3 and R4 may be the same or different, and each represents an alkyl group, a cycloalkyl group, an aryl group or an alkylaryl group] of the benzotriazole-alkylenebisphenol compound represented by An electrophotographic photoreceptor comprising a photosensitive layer containing one or more kinds and one or more kinds of charge transfer agents having an arylamino group in a molecule.
[0012]
In the present invention, the charge transfer agent having an arylamino group in the molecule is represented by the following general formula [2], [3] or [4].
[0013]
[Chemical 9]

[0014]
[Chemical Formula 10]

[0015]
Embedded image

[0016]
[In Formula [2], Formula [3], and Formula [4], Z represents a divalent group —O—, —S—, or —N (R10) —. R5 and R6 may be the same or different and are each an unsubstituted or substituted linear or branched alkyl group having 1 to 12 carbon atoms, an unsubstituted or substituted carbon group having 7 to 20 carbon atoms. A linear or branched aralkyl group or an unsubstituted or substituted aryl group having 1 to 4 rings is represented. R7, R8, R9 and R11 are each a hydrogen atom, an unsubstituted or substituted linear or branched alkyl group having 1 to 12 carbon atoms, an unsubstituted or substituted carbon group having 7 to 20 carbon atoms. Linear or branched aralkyl group, linear or branched alkoxy group having 1 to 4 carbon atoms, aryloxy group, acyl group, alkoxycarbonyl group having 2 to 5 carbon atoms, halogen atom, nitro group Represents a monoalkyl group substituted with an alkyl group having 1 to 4 carbon atoms, a dialkylamino group substituted with an alkyl group having 1 to 4 carbon atoms, or an amide group. R10 is an unsubstituted or substituted linear or branched alkyl group having 1 to 12 carbon atoms, or an unsubstituted or substituted linear or branched aralkyl group having 1 to 12 carbon atoms. Represents. When R5 to R11 have a substituent, the substituent represents a halogen atom, an alkoxy group, an aryloxy group, a dialkylamino group or an alkylthio group, and also represents an alkyl group only when R5 or R6 is an aryl group. ]
An electrophotographic photoreceptor comprising a photosensitive layer which is a drazone compound and contains one or more hydrazone compounds.
[0017]
In the present invention, the charge transfer agent having an arylamino group in the molecule is represented by the following general formula [5].
[0018]
Embedded image

[0019]
[In the formula [5], R12 represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a substituted amino group. m is an integer of 1 or 2, and when m = 2, both groups may be the same or different, and both groups may be bonded to each other to form a tetramethylene ring or a trimethylene ring. R13 represents an unsubstituted or substituted phenyl group. In this case, examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, and a phenyl group. R14 represents hydrogen, a halogen atom, an alkyl group, an alkoxy group or an alkylamino group. R15 and R16 may be the same or different and are each an unsubstituted or substituted phenyl group, an unsubstituted or substituted naphthyl group, an unsubstituted or substituted anthryl group, an unsubstituted or substituted fluorenyl group. Represents a group or an unsubstituted or substituted heterocyclic group, and examples of the substituent in this case include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, and a phenyl group. An electrophotographic photoreceptor characterized by having a photosensitive layer containing one or more of the styryl compounds.
[0020]
In the present invention, the charge transfer agent having an arylamino group in the molecule is represented by the following general formula [6].
[0021]
Embedded image

[0022]
[In the formula [6], R17 represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and R18, R'18, R19 and R'19 may be the same or different. Represents a group, a halogen atom or a substituted amino group. n is an integer of 1 or 2, and when n = 2, two groups substituted by the same phenyl group may be the same or different. p is an integer of 1 or 2, and when p = 2, two groups substituted by the same phenyl group may be the same or different. An electrophotographic photoreceptor characterized by having a photosensitive layer containing one or more of the benzidine compounds.
[0023]
In the present invention, the benzotriazole-alkylene bisphenol compound is represented by the following general formula [7].
[0024]
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[0025]
Specific examples of the benzotriazole-alkylene bisphenol compound represented by the general formula [1] are shown. The compounds used in the present invention are not limited to these compounds.
[0026]
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[0027]
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[0028]
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[0029]
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[0030]
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[0031]
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[0032]
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[0033]
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[0036]
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[0037]
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[0038]
The electrophotographic photoreceptor of the present invention has a photosensitive layer containing one or more charge transfer agents having an arylamino group in the molecule, and further contains the above benzotriazole-alkylene bisphenol compound. Contains one or more species. The diffusion of the benzotriazole-alkylene bisphenol compound used in the present invention is suppressed even by drying at high temperature during the preparation of the photoreceptor, and the photodegradation suppression and antioxidant effect on the charge transport agent having an arylamino group in the molecule Therefore, there is no need for additional preparation at the time of initial addition, and it is possible to prevent a decrease in the physical properties, particularly a decrease in surface resistance, due to an increase in the additive. Further, since it acts on the charge transport agent having an arylamino group in the molecule to surely suppress the photodegradation and prevent the oxidation, it is possible to prevent the image of the photoreceptor from being lowered and the lifespan thereof being shortened.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
There are various types of photosensitive layers, and any of them can be used as the photosensitive layer of the electrophotographic photoreceptor of the present invention. As representative examples, those photoreceptors are shown in FIGS.
[0040]
1 is a charge transfer agent having an arylamino group in a molecule on a conductive support 1, which are represented by the general formulas [2], [3], [4], [5], and [6]. A photosensitive layer 2 comprising a sensitizing dye and a benzotriazole-alkylene bisphenol compound, which may be a specific amine compound represented by the formula (1), is provided.
[0041]
2 is a charge transfer agent having an arylamino group in the molecule on the conductive support 1-these are represented by the general formulas [2], [3], [4], [5], and [6]. The photosensitive layer 21 in which the charge generator 4 is dispersed is provided in the charge transport medium 3 made of a benzotriazole-alkylene bisphenol compound. In this photoreceptor, the charge generating agent absorbs light to generate charge carriers, which are transported by the charge transport medium. In this case, it is desirable that the charge transport agent is transparent to light that generates charge carriers. Since the amine compound has almost no absorption in the visible wavelength region, it satisfies the condition that the charge generating agent and the absorption wavelength region do not overlap.
[0042]
3 includes a charge generation layer 5 mainly composed of a charge generation agent 4 on a conductive support 1, and a charge transfer agent having an arylamino group, which are represented by general formulas [2], [3], [ 4], [5] and [6] may be used, and a photosensitive layer 22 composed of a laminate of a charge transport layer 3 made of a benzotriazole-alkylene bisphenol compound may be provided. . In this photoreceptor, the light transmitted through the charge transport layer 3 reaches the charge generation layer 5 and is absorbed by the charge generation agent 4 to generate charge carriers. The charge carriers are injected into the charge transport layer 3 and transported.
[0043]
4 is provided with a photosensitive layer 23 in which the order of stacking the charge generation layer 5 and the charge transport layer 3 of the photoreceptor of FIG. 3 is reversed. The generation and transport of charge carriers can be explained by the same mechanism as described above.
[0044]
The photoreceptor shown in FIG. 5 is provided with a photosensitive layer 24 in which a protective layer 6 is further laminated on the charge generation layer 5 of the photoreceptor shown in FIG. 4 for the purpose of improving mechanical strength.
[0045]
The photoreceptor of the present invention can be produced according to a conventional method as follows. For example, the benzotriazole-alkylene bisphenol compound represented by the general formula [1] described above and the specific amine compound represented by the general formulas [2], [3], [4], [5], and [6] Is dissolved in a suitable solvent together with a binder resin, and a coating solution is prepared by adding a charge generating substance, a sensitizing dye, an electron-withdrawing compound, a plasticizer, a pigment, and other additives as necessary. By applying this coating solution on a conductive support and drying it to form a photosensitive layer of several μm to several tens of μm, a photoconductor can be produced. In the case of a photosensitive layer comprising two layers of a charge generation layer and a charge transport layer, the charge generation layer is formed on the charge transport layer obtained by applying the coating solution on the charge generation layer or by applying the coating solution. Can be produced. In addition, the photoreceptor manufactured in this manner may be provided with an undercoat layer, an intermediate layer, and a barrier layer as necessary.
[0046]
As the solvent for preparing the coating solution, polar organic solvents such as tetrahydrofuran, 1,4-dioxane, methyl ethyl ketone, cyclohexanone, acetonitrile, N, N-dimethylformamide, and ethyl acetate, aromatic organic solvents such as toluene and xylene, Chlorine hydrocarbon solvents such as dichloromethane and 1,2-dichloroethane can be used. A solvent having high solubility with respect to the amine compound and the binder resin is preferably used.
[0047]
As binder resins, polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic ester, methacrylic ester butadiene, polyvinyl acetal, polycarbonate, polyester, polyphenylene oxide, polyurethane cellulose ester, phenoxy resin And various resins compatible with benzotriazole-alkylene bisphenol compounds and specific amine compounds, such as silicon resins and epoxy resins. Moreover, the usage-amount of binder resin is 0.4-10 weight times normally with respect to an amine compound, Preferably it is the range of 0.5-5 weight times.
[0048]
Charge transport agents having an arylamino group in the molecule-these may be specific amine compounds represented by the general formulas [2], [3], [4], [5], [6] On the other hand, it is effective to add 1 to 40% by weight, preferably 3 to 30% by weight, of one or more benzotriazole-alkylene bisphenol compounds represented by the general formula [1].
[0049]
Examples of charge generators include α-type, β-type, τ-type, X-type and other crystalline metal-free phthalocyanines, copper phthalocyanines, aluminum phthalocyanines, zinc phthalocyanines, α-type, β-type, Y-type oxotitanyl phthalocyanines, cobalt phthalocyanines. Hydroxygallium phthalocyanine, chloroaluminum phthalocyanine, chloroindium phthalocyanine, phthalocyanine pigments such as titanyl phthalocyanine having large peaks at 9.6 ° and 27.2 ° of black angle 2θ with respect to Cu-Kα rays (wavelength 1.541). Azo pigment having triphenylamine skeleton, azo pigment having diphenylamine skeleton, azo pigment having carbazole skeleton, azo pigment having fluorene skeleton, azo pigment having oxadiazole skeleton, azo pigment having bisstilbene skeleton, dibenzothiophene skeleton Azo pigments such as azo pigments having a stilbene skeleton, azo pigments having a distyrylbenzene skeleton, and trisazo pigments having a carbazole skeleton. Perylene pigments such as perylene acid anhydride and perylene imide. Polycyclic quinone pigments such as anthraquinone derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives, pyranthrone derivatives, violanthrone derivatives and isoviolanthrone derivatives. Diphenylmethane and triphenylmethane pigments. Cyanine and azomethine pigments. Examples include indigoid pigments, bisbenzimidazole pigments, azulenium salts, pyrylium salts, thiapyrylium salts, benzopyrylium salts, and squarylium salts. These may be used alone or as a mixture of two or more thereof as necessary.
[0050]
Sensitizing dyes include triarylmethane dyes such as methyl violet, brilliant green, crystal violet, and acid violet, rhodamine B, eosin S, xanthene dyes such as rose bengal, thiazine dyes such as methylene blue, benzopyrylium salts A pyrylium dye, a thiapyrylium dye, a cyanine dye, or the like can be used.
[0051]
Examples of electron-withdrawing compounds that form charge transfer complexes with amine compounds include quinones such as chloranil, 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 2-chloroanthraquinone, phenanthrenequinone, and the like. Aldehydes such as nitrobenzaldehyde, ketones such as 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, anhydrous Acid anhydrides such as phthalic acid and 4-chloronaphthalic anhydride, cyano compounds such as tetracyanoethylene, terephthalalmaleonitrile, 9-anthrylmethylidenemaleonitrile, 3-benzalphthalide, 3- (α-cyano- p-nitrobenzal) -4,5,6,7-tetrachloro Phthalide such as Tarido and the like.
[0052]
Further, the photosensitive layer of the present invention may contain a known plasticizer for the purpose of improving the film formability, flexibility and mechanical strength. As the plasticizer, for example, phthalic acid ester, phosphoric acid ester, chlorinated paraffin, methyl naphthalene, epoxy compound, chlorinated fatty acid ester and the like can be used.
[0053]
As the conductive support on which the photosensitive layer of the present invention is formed, materials used in known electrophotographic photoreceptors can be used. Conductive treatment by applying a metal drum, sheet of aluminum, stainless steel, copper, etc. or a laminate of these metals, a deposit, or a conductive material such as metal powder, carbon black, copper iodide, or polymer electrolyte together with an appropriate binder. It is possible to use a plastic film, a plastic drum, paper, a paper tube, or a plastic film or a plastic drum imparted with conductivity by containing a conductive substance.
[0054]
【Example】
Hereinafter, the present invention will be described specifically by way of examples. The part in an Example represents a weight part and a density | concentration represents%.
[0055]
[Example 1]
X-type metal-free phthalocyanine (charge generator No. 1) as a charge generator
[0056]
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[0057]
1.5 parts was added to 50 parts of a 3% cyclohexanone solution of polyvinyl butyral resin (S-REC BL-S, manufactured by Sekisui Chemical Co., Ltd.) and dispersed with an ultrasonic disperser for 1 hour. The obtained dispersion is applied on the aluminum surface of an aluminum vapor-deposited PET film, which is a conductive support, using a wire bar and dried at 110 ° C. for 1 hour under normal pressure to form a charge generation layer having a thickness of 0.4 μm. did. On the other hand, 16 parts of the following benzotriazole-alkylene bisphenol compound (additive No. 1) as an additive
[0058]
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[0059]
And the following hydrazone compound (charge transport agent No. 1) as a charge transport agent
[0060]
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[0061]
144 parts are added to 2000 parts of a 9.0% 1,2-dichloroethane solution of polycarbonate resin (Iupilon Z, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) and ultrasonically applied to completely dissolve the benzotriazole-alkylene bisphenol compound and hydrazone compound. I let you. This solution was applied onto the charge generation layer with a wire bar and dried at 120 ° C. for 1 hour under normal pressure to form a charge transport layer having a thickness of 20 μm, thereby preparing a photoreceptor.
[0062]
[Example 2]
In Example 1, the charge transfer agent No. Hydrazone compound (charge transfer agent No. 2)
[0063]
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[0064]
A photoconductor was prepared in the same manner as in Example 1 except that was used.
[0065]
[Example 3]
In Example 1, the charge transfer agent No. Benzidine compound (charge transfer agent No. 3)
[0066]
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[0067]
A photoconductor was prepared in the same manner as in Example 1 except that was used.
[0068]
[Example 4]
In Example 1, the charge transfer agent No. Benzidine compound (charge transporting agent No. 4)
[0069]
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[0070]
A photoconductor was prepared in the same manner as in Example 1 except that was used.
[0071]
[Comparative Example 1]
In Example 2, additive no. 1 instead of the following benzotriazole compound (additive No. 2)
[0072]
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[0073]
And the following phenol compound (additive No. 3)
[0074]
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[0075]
A comparative photoconductor was prepared in the same manner as in Example 2 except that the 1: 1 weight ratio mixture was used.
[Example 5]
In Example 2, the charge generating agent no. A photoconductor was prepared in the same manner as in Example 2 except that τ-type metal-free phthalocyanine (charge generating agent No. 2) was used instead of 1.
[0076]
[Example 6]
In Example 5, the charge transfer agent No. The following styryl compound (charge transfer agent No. 5)
[0077]
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[0078]
And the following styryl compound (charge transfer agent No. 6)
[0079]
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[0080]
A photoreceptor was prepared in the same manner as in Example 5 except that the 1: 1 weight ratio mixture was used.
[0081]
[Example 7]
In Example 5, the charge transfer agent No. A photoconductor was prepared in the same manner as in Example 5 except that a benzidine compound (charge transfer agent No. 4) was used instead of 2.
[0082]
[Example 8]
In Example 5, the charge transfer agent No. Benzidine compound (charge transfer agent No. 7)
[0083]
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[0084]
A photoreceptor was prepared in the same manner as in Example 5 except that was used.
[0085]
[Comparative Example 2]
In Example 6, additive no. A comparative photoconductor was prepared in the same manner as in Example 6 except that a 1: 1 weight ratio mixture of a benzotriazole compound (Additive No. 2) and a phenol compound (Additive No. 3) was used instead of 1. did.
[0086]
[Example 9]
In Example 2, the charge generating agent no. Instead of using 1, Y-type oxotitanyl phthalocyanine (charge generating agent No. 3)
[0087]
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[0088]
A photoconductor was prepared in the same manner as in Example 2 except that was used.
[0089]
[Example 10]
In Example 6, the charge generating agent no. A photoconductor was prepared in the same manner as in Example 6 except that α-type oxotitanyl phthalocyanine (charge generating agent No. 4) was used instead of 2.
[0090]
[Comparative Example 3]
In Example 10, additive no. A comparative photoconductor was prepared in the same manner as in Example 10 except that a 1: 1 weight ratio mixture of a benzotriazole compound (additive No. 2) and a phenol compound (additive No. 3) was used instead of using 1. did.
[0091]
[Examples 1 to 10, Comparative Examples 1 to 3]
The photoconductors produced in Examples 1 to 10 and Comparative Examples 1 to 3 were subjected to electrophotographic characteristic evaluation using a photosensitive drum characteristic measuring device (trade name “ELYSIA-II” manufactured by Trek Japan Co., Ltd.). First, the photosensitive member was subjected to corona discharge of −5.0 kV in a dark place, and then the charging potential V0 when a 50 lux erase lamp was turned on was measured. Subsequently, it exposed with the monochromatic light of 780nm-40microW, and calculated | required the residual potential Vr. Next, this photoreceptor was exposed to 20 ppm ozone gas in a room under fluorescent lamp illumination for 5 days, and then the charging potential V0 and the residual potential Vr were measured in the same manner as before the exposure. The results are shown in [Table 1].
[0092]
[Table 1]

[0093]
[Example 11]
The following bisazo pigment (charge generator No. 5) as a charge generator
[0094]
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[0095]
1.0 part and 8.6 parts of 5% tetrahydrofuran solution of polyester resin (Byron 200, manufactured by Toyobo Co., Ltd.) are added to 83 parts of tetrahydrofuran. Made for 1 hour and dispersed. The obtained dispersion is applied onto the aluminum surface of an aluminum vapor-deposited PET film, which is a conductive support, using a wire bar and dried at 60 ° C. for 2 hours under normal pressure to form a charge generation layer having a thickness of 0.3 μm. did. On the other hand, 16 parts of a benzotriazole-alkylene bisphenol compound (additive No. 1) as an additive and 144 parts of a hydrazone compound (charge transport agent No. 1) as a charge transport agent were added to a polycarbonate resin (Iupilon Z, Mitsubishi Engineering Plastics). The benzotriazole-alkylene bisphenol compound and the hydrazone compound were completely dissolved by applying ultrasonic waves in addition to 2000 parts of a 9.0% 1,2-dichloroethane solution. This solution was applied onto the charge generation layer with a wire bar and dried at 120 ° C. for 1 hour under normal pressure to form a charge transport layer having a thickness of 20 μm, thereby preparing a photoreceptor.
[0096]
[Example 12]
In Example 11, the charge transfer agent No. A photoconductor was prepared in the same manner as in Example 11 except that a styryl compound (charge transfer agent No. 6) was used instead of 1.
[0097]
[Example 13]
In Example 11, the charge transfer agent No. A photoconductor was prepared in the same manner as in Example 11 except that a 1: 1 weight ratio mixture of a styryl compound (charge transfer agent No. 5) and a styryl compound (charge transfer agent No. 6) was used instead of using 1. .
[0098]
[Comparative Example 4]
In Example 12, additive no. A photoconductor for comparison was produced in the same manner as in Example 12 except that a 1: 1 weight ratio mixture of a benzotriazole compound (additive No. 2) and a phenol compound (additive No. 3) was used instead of using 1. did.
[0099]
[Example 14]
The following trisazo pigment (charge generator No. 6) as a charge generator
[0100]
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[0101]
1.0 part and 8.6 parts of 5% tetrahydrofuran solution of polyvinyl butyral resin (S-REC BL-S, manufactured by Sekisui Chemical Co., Ltd.) are added to 83 parts of tetrahydrofuran, put into an agate pot containing agate spheres, and planetary fine particles The mixture was rotated for 1 hour with a pulverizer (manufactured by Fritsch) and dispersed. The obtained dispersion is applied onto the aluminum surface of an aluminum vapor-deposited PET film, which is a conductive support, using a wire bar and dried at 60 ° C. for 2 hours under normal pressure to form a charge generation layer having a thickness of 0.3 μm. did. On the other hand, the following benzotriazole-alkylene bisphenol compound (additive No. 4) as an additive
[0102]
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[0103]
16 parts and the following styryl compound as a charge transporting agent (charge transporting agent No. 8)
[0104]
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[0105]
144 parts are added to 2000 parts of a 9.0% 1,2-dichloroethane solution of polycarbonate resin (Iupilon Z, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) and ultrasonically applied to completely dissolve the benzotriazole-alkylene bisphenol compound and styryl compound. I let you. This solution was applied onto the charge generation layer with a wire bar and dried at 120 ° C. for 1 hour under normal pressure to form a charge transport layer having a thickness of 20 μm, thereby preparing a photoreceptor.
[0106]
[Example 15]
In Example 14, the charge transfer agent No. Benzidine compound (charge transfer agent No. 9)
[0107]
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[0108]
A photoconductor was prepared in the same manner as in Example 14 except that was used.
[0109]
[Comparative Example 5]
In Example 15, additive no. A photoconductor for comparison was produced in the same manner as in Example 15 except that a 1: 1 weight ratio mixture of a benzotriazole compound (Additive No. 2) and a phenol compound (Additive No. 3) was used instead of 4. did.
[0110]
[Examples 11 to 15, Comparative Examples 4 and 5]
The photoconductors produced in Examples 11 to 15 and Comparative Examples 4 and 5 were evaluated for electrophotographic characteristics using a photosensitive drum characteristic measuring device (trade name “ELYSIA-II” manufactured by Trek Japan Co., Ltd.). First, the photosensitive member was subjected to corona discharge of −5.0 kV in a dark place, and then the charging potential V0 when a 50 lux erase lamp was turned on was measured. Next, exposure was performed with an image exposure of 70 lux, and a residual potential Vr was obtained. Next, this photoreceptor was exposed to 20 ppm ozone gas in a room under fluorescent lamp illumination for 5 days, and then the charging potential V0 and the residual potential Vr were measured in the same manner as before the exposure. The results are shown in [Table 2].
[0111]
[Table 2]

[0112]
As is apparent from the results of [Table 1] and [Table 2], in the examples using the benzotriazole-alkylene bisphenol compound of the present invention as an additive, the decrease in the charged potential V0 of the photoreceptor is suppressed even after exposure to ozone gas. It can be seen that the increase in the residual potential (Vr) of the photoreceptor is also suppressed. On the other hand, in the comparative example, it can be seen that the charging potential V0 of the photoreceptor decreases after exposure to ozone gas, and the residual potential (Vr) of the photoreceptor also increases.
[0113]
【The invention's effect】
The electrophotographic photoreceptor using a charge transfer agent having an arylamino group in the molecule of the present invention and added with a benzotriazole-alkylene bisphenol compound prevents a decrease in the charged potential even after exposure to ozone gas, and increases the residual potential. Is suppressed. Furthermore, since the amount of additive added is small, it does not impair the basic performance of electrophotography, and exhibits excellent properties in repeated stability.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a single-layer electrophotographic photoreceptor.
FIG. 2 is a cross-sectional view of a single-layer photoconductor for electrophotography in which a charge generating material is dispersed.
FIG. 3 is a cross-sectional view of an electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are laminated in this order on a conductive support.
FIG. 4 is a cross-sectional view of an electrophotographic photoreceptor in which a charge transport layer and a charge generation layer are laminated in this order on a conductive support.
FIG. 5 is a cross-sectional view of an electrophotographic photoreceptor provided with a protective layer.
[Explanation of symbols]
1 Conductive support
2, 21, 22, 23, 24 Photosensitive layer
3 Charge transport medium, charge transport layer
4 Charge generation materials
5 Charge generation layer
6 Protective layer

Claims (6)

On the conductive support, the following general formula [1]

[Wherein, X represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or an alkylaryl group, R1 represents an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or an aralkyl group, and R2 represents A hydrogen atom, an alkyl group or an aryl group, R3 and R4 may be the same or different, and each represents an alkyl group, a cycloalkyl group, an aryl group or an alkylaryl group] of the benzotriazole-alkylenebisphenol compound represented by 1. An electrophotographic photoreceptor comprising a photosensitive layer containing one or more kinds and one or more charge transfer agents having an arylamino group in the molecule. A charge transfer agent having an arylamino group in the molecule is represented by the following general formula [2], [3] or [4].

[2]

[In Formula [2], Formula [3], and Formula [4], Z represents a divalent group —O—, —S—, or —N (R10) —. R5 and R6 may be the same or different and are each an unsubstituted or substituted linear or branched alkyl group having 1 to 12 carbon atoms, an unsubstituted or substituted carbon group having 7 to 20 carbon atoms. A linear or branched aralkyl group or an unsubstituted or substituted aryl group having 1 to 4 rings is represented. R7, R8, R9 and R11 are each a hydrogen atom, a linear Moshiku 1 -C an unsubstituted or substituted 12 branched alkyl group, C 7 carbon atom an unsubstituted or substituted 20 linear or branched aralkyl groups, linear or branched alkoxy groups having 1 to 4 carbon atoms, aryloxy groups, acyl groups, alkoxycarbonyl groups having 2 to 5 carbon atoms, halogen atoms, It represents a nitro group, a monoalkyl group substituted with an alkyl group having 1 to 4 carbon atoms, a dialkylamino group substituted with an alkyl group having 1 to 4 carbon atoms, or an amide group. R10 is an unsubstituted or substituted linear or branched alkyl group having 1 to 12 carbon atoms, or an unsubstituted or substituted linear or branched aralkyl group having 1 to 12 carbon atoms. Represents. When R5 to R11 have a substituent, the substituent represents a halogen atom, an alkoxy group, an aryloxy group, a dialkylamino group or an alkylthio group, and only when R5 or R6 is an aryl group, an alkyl group is also represented. 2. The electrophotographic photoreceptor according to claim 1, further comprising a photosensitive layer containing one or more of the hydrazone compounds. A charge transfer agent having an arylamino group in the molecule is represented by the following general formula [5].

[In Formula [5], R12 represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a substituted amino group. m is an integer of 1 or 2, and when m = 2, both groups may be the same or different, and both groups may be bonded to each other to form a tetramethylene ring or a trimethylene ring. R13 represents an unsubstituted or substituted phenyl group, and examples of the substituent in this case include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, and a phenyl group. R14 represents hydrogen, a halogen atom, an alkyl group, an alkoxy group or an alkylamino group. R15 and R16 may be the same or different, and each is an unsubstituted or substituted phenyl group, an unsubstituted or substituted naphthyl group, an unsubstituted or substituted anthryl group, an unsubstituted or substituted fluorenyl Represents a group or an unsubstituted or substituted heterocyclic group, and examples of the substituent in this case include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, and a phenyl group. 2. The electrophotographic photoreceptor according to claim 1, further comprising a photosensitive layer containing one or more of the styryl compounds represented by the formula: A charge transfer agent having an arylamino group in the molecule is represented by the following general formula [6].

[6]
[In the formula [6], R17 represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, and R18, R′18, R19 and R′19 may be the same or different. Represents a group, a halogen atom or a substituted amino group. n is an integer of 1 or 2, and when n = 2, two groups substituted by the same phenyl group may be the same or different. p is an integer of 1 or 2, and when p = 2, two groups substituted by the same phenyl group may be the same or different. The electrophotographic photoreceptor according to claim 1, further comprising a photosensitive layer containing one or more of the benzidine compounds represented by the formula: The benzotriazole-alkylene bisphenol compound is represented by the following general formula [7]

[7]
[Wherein R1 represents an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or an aralkyl group, R2 represents a hydrogen atom, an alkyl group or an aryl group, R3 and R4 may be the same or different, and each represents an alkyl group. 5. The electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor has a structure represented by: a group, a cycloalkyl group, an aryl group, or an alkylaryl group. 1 to 40% by weight of one or more benzotriazole-alkylene bisphenol compounds represented by the general formula [1] are added to the charge transporting agent having an arylamino group in the molecule. The electrophotographic photosensitive member according to claim 1.

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