JP3788923B2 - Electrophotographic photosensitive member and electrophotographic apparatus using the same - Google Patents

Description

【００２６】
（式中、Ｒ₁〜Ｒ₄は置換基を有してもよいアリール基または置換基を有してもよいアラルキル基を表す。）
【００２７】
本発明に従えば、特定のブタジエン化合物を電荷輸送物質として用いることによって、非常に高移動度であるので、高感度、高画質および高解像度のすべてをより満足する電子写真感光体を提供することができる。
【００２８】
また本発明は、前記感光層は、電荷輸送物質として、下記一般式（２）で示されるビスアミン化合物を含有することを特徴とする。
【００２９】
【化４】

【００３０】
（式中、Ｒ₅およびＲ₆は、各々水素原子、アルキル基、アルコキシ基、ハロゲン原子、アルコキシカルボニル基、または置換基を有してもよいアミノ基を表す。Ｒ₇は、アルキル基またはアルコキシ基を表す。）
【００３１】
本発明に従えば、特定のビスアミン化合物を電荷輸送物質として用いることによって、非常に高移動度であるので、高感度、高画質および高解像度のすべてをより満足する電子写真感光体を提供することができる。
【００３２】
また本発明は、前記感光層が、少なくとも、前記結晶性フタロシアニン組成物を電荷発生物質として含有する電荷発生層と、電荷輸送物質を含有する電荷輸送層とが積層されて成ることを特徴とする。
【００３３】
本発明に従えば、電荷発生層中に前記特定のＸ線回折スペクトルを有する結晶性フタロシアニン組成物を電荷発生物質として用いることによって、高感度、高画質および高解像度のすべてを満足する積層型の電子写真感光体を提供することができる。
【００３４】
また本発明は、前記電子写真感光体を搭載し、該電子写真感光体に対して画像露光する半導体レーザまたは発光ダイオードを備えたことを特徴とする電子写真装置である。
【００３５】
本発明に従えば、半導体レーザや発光ダイオード（ＬＥＤ）を露光光源として用いる電子写真装置において、前記電子写真感光体を搭載することによって、これらの露光光源により照射され周辺部に広がった弱い光に対しては感光せず、ドットが広がることがなく、より良好な潜像形成ができるので、高画質を得ることができる。
【００３６】
また本発明は、帯電されて画像露光された電子写真感光体を、反転現像して画像を得る手段を備えたことを特徴とする。
【００３７】
本発明に従えば、反転現像プロセスを用いる電子写真装置において、前記電子写真感光体を搭載することによって、露光以外の要因で表面電荷が減少することがなく、白地にトナーが付着する黒ポチの発生がなく、高感度、高画質および高解像度のすべてを満足する、デジタルデータの出力に適した複写機、プリンタおよびファクシミリなどの電子写真装置を提供することができる。
【００３８】
【発明の実施の形態】
以下、本発明を詳細に説明する。
【００３９】
図１は、積層型の電子写真感光体の構成例を示す断面図である。図２は、単層型の電子写真感光体の構成例を示す断面図である。図１の積層型感光体において、導電性支持体２上に感光層４を設け、感光層４が電荷発生物質８およびバインダ樹脂７を含有する電荷発生層５と、電荷輸送物質９およびバインダ樹脂１８を含有する電荷輸送層６との２層から構成されている。図２の単層型感光体において、導電性支持体２上に感光層１４を設け、感光層１４中に電荷輸送物質９と電荷発生物質８とバインダ樹脂１９とが含有されている。
【００４０】
本発明による電子写真感光体の構成としては、図１のような積層型および図２のような単層型のいずれの感光体でもよい。本発明による電子写真感光体は、積層型では電荷発生層５に、単層型では感光層１４に、特定の結晶性フタロシアニン組成物を電荷発生物質８として用いることを特徴とする。
【００４１】
電荷発生物質８として用いる特定の結晶性フタロシアニン組成物は、具体的には、下記一般式（３）で示される金属フタロシアニンおよび一般式（４）で示される無金属フタロシアニンなどのフタロシアニン化合物を有する。特定の結晶性フタロシアニン組成物は、以下に示すＸ線回折スペクトルにおける特性を示す限り、金属フタロシアニンおよび無金属フタロシアニンのうちのいずれか一方だけを有してもよく、これらを混合した組成物であってもよい。
【００４２】
【化５】

【００４３】
【化６】

【００４４】
（式（３）および（４）中、Ｘ₁〜Ｘ₄は各々、水素原子、ハロゲン原子、アルキル基またはアルコキシ基を表し、ｔ、ｕ、ｖおよびｗは０〜４の整数を表す。）
【００４５】
前記特定の結晶性フタロシアニン組成物は、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、少なくとも７．０°、７．６°、９．０°、１３．６°、１６．８°および２７．２°にピークを示す結晶性フタロシアニン組成物▲１▼である。
【００４６】
前記結晶性フタロシアニン組成物▲１▼は、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、さらに７．０°に対する１６．８°のピークの高さの比が２倍よりも小さい結晶性フタロシアニン組成物▲２▼であることが好ましい。
【００４７】
また、前記結晶性フタロシアニン組成物▲１▼または▲２▼は、チタニルフタロシアニンと無金属フタロシアニンとから成る結晶性フタロシアニン組成物▲３▼を含有しており、この結晶性フタロシアニン組成物▲３▼はＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、少なくとも７．０°、９．０°、１４．１°、１８．０°、２３．７°および２７．２°に主要なピークを持つことが好ましい。
【００４８】
また、前記結晶性フタロシアニン組成物▲１▼または▲２▼は、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、少なくとも７．６°、９．０°、１６．８°、１７．３°および２２．３°に主要なピークを持つχ型無金属フタロシアニン▲４▼を含有していることがより好ましい。
【００４９】
特に、前記結晶性フタロシアニン組成物▲１▼または▲２▼は、フタロシアニン組成物▲３▼とχ型無金属フタロシアニン▲４▼との両方を含有していることが、最も好ましい。
【００５０】
前記χ型無金属フタロシアニンは、結晶性フタロシアニン組成物中に１０〜７０重量％含有されていることが好ましい。１０重量％未満ではドットが正確に形成されないで高解像度および高画質が得られず、７０重量％を超えるとドットがみだれて黒べた濃度が低下して高解像度および高感度が得られないからである。
【００５１】
本発明による電子写真感光体は、以上のような、特定のフタロシアニンを電荷発生物質８として感光層４または１４に含有することによって構成される。また、前述のように、本発明による電子写真感光体は、図１に示したような積層型および図２に示したような単層型のいずれの感光体でもよい。
【００５２】
導電性支持体２としては、積層型および単層型のいずれの感光体においても、たとえばアルミニウム、アルミニウム合金、ステンレス鋼、鉄、金、銀、銅、亜鉛、ニッケルおよびチタンなどの金属材料や、アルミニウム、金、銀、銅、ニッケル、酸化インジウムおよび酸化錫などを蒸着したプラスチック基体、ポリエステルフィルムや紙、導電性粒子を含有したプラスチックおよび紙、ならびに、導電性ポリマーを含有するプラスチックなどが使用できる。それらの形状としては、ドラム状、シート状およびシームレスベルト状などが挙げられる。
【００５３】
導電性支持体２上には、図１に示したような積層型感光体の場合には感光層４が形成され、図２に示したような単層型感光体の場合には感光層１４が形成される。
【００５４】
積層型電子写真感光体の感光層４は、導電性支持体２上に、前記特定の結晶性フタロシアニン組成物を含有する電荷発生層５と、電荷輸送層６とが順次積層されて構成される。
【００５５】
電荷発生層５の形成方法としては、前記特定のフタロシアニン化合物を粉砕、分散して得られる電荷発生層用塗布液を、導電性支持体２上に塗布することによる方法がある。具体的には、前記特定のフタロシアニン化合物の微粒子に有機溶媒を加え、ボールミル、サンドグラインダ、ペイントシェーカおよび超音波分散機などによって粉砕し、分散して電荷発生層用塗布液を調製する。該電荷発生層用塗布液を、シート形状の感光体を形成する場合にはベーカーアプリケータ、バーコータ、キャスティングおよびスピンコートなどにより、ドラム形状の感光体を形成する場合にはスプレイ法、垂直リング法および浸漬塗布法などにより、導電性支持体２上に塗布して電荷発生層５を形成する。
【００５６】
図３は、浸漬塗布法において用いる浸漬塗布装置の一例を示す構成図である。塗布層１３内に満たされた塗布液１２中に、円筒状の導電性の基体２が浸漬される。基体２は、モータ１１を備える昇降装置１０によって下降され、塗布液１２中に浸漬される。昇降装置１０はモータ１１の回転量を制御することによって、所望の深さだけ基体２を塗布槽１３に浸漬することができる。基体２は充分浸漬された後、昇降装置１０によって一定速度または逐次変化する速度で引上げられる。基体浸漬時に塗布槽１３からオーバフローした塗布液１２は、回収槽１４に回収される。回収された塗布液は、攪拌装置１５にて攪拌された後、ポンプ１６によって塗布槽１３に戻される。
【００５７】
電荷発生層用塗布液には、結着性を増すためにバインダ樹脂７として、たとえばポリエステル樹脂、ポリビニルアセテート、ポリアクリル酸エステル、ポリカーボネート、ポリアリレート、ポリビニルアセトアセタール、ポリビニルプロピオナール、ポリビニルブチラール、フェノキシ樹脂、エポキシ樹脂、ウレタン樹脂、メラミン樹脂、シリコーン樹脂、アクリル樹脂、セルロースエステル、セルロースエーテル、塩化ビニル−酢酸ビニル共重合体樹脂などを加えてもよい。また、電荷発生層５には必要に応じて、塗布性を改善するためのレベリング剤、酸化防止剤および増感剤などの各種添加剤を含んでいてもよい。
【００５８】
電荷発生層５の膜厚は、０．０５〜５μｍが好ましく、特に０．１〜１μｍが好適である。
【００５９】
電荷輸送層６は、主に電荷輸送物質９とバインダ樹脂１８から構成される。電荷輸送物質９としては、２，４，７−トリニトロフルオレノン、テトラシアノキノジメタンおよびジフェノキノンなどの電子吸引性物質、カルバゾール、インドール、イミダゾール、オキサゾール、ピラゾール、オキサジアゾール、ピラゾリンおよびチアジアゾールなどの複素環化合物、アニリン誘導体、ヒドラゾン化合物、芳香族アミン誘導体、スチリル化合物、ブタジエン化合物、ビスアミン化合物、エナミン化合物、ならびに、これらの化合物からなる基を主鎖または側鎖に有する重合体などの電子供与性物質が挙げられる。特に、特定のスチリル系化合物、下記一般式（１）で示されるブタジエン化合物および下記一般式（２）で示されるビスアミン化合物は、非常に高移動度であるので高感度化および高解像度化に好適である。これらの電荷輸送物質９は、単独でも、複数を混合して用いてもよい。
【００６０】
【化７】

【００６１】
（式中、Ｒ₁〜Ｒ₄は置換基を有してもよいアリール基または置換基を有してもよいアラルキル基を表す。）
【００６２】
【化８】

【００６３】
（式中、Ｒ₅およびＲ₆は、各々水素原子、アルキル基、アルコキシ基、ハロゲン原子、アルコキシカルボニル基、または置換基を有してもよいアミノ基を表す。Ｒ₇は、アルキル基またはアルコキシ基を表す。）
一般式（１）で示されるブタジエン化合物の具体例を表１および表２に示す。
【００６４】
【表１】

【００６５】
【表２】

【００６６】
一般式（２）で示されるビスアミン化合物の具体例を表３に示す。
【００６７】
【表３】

【００６８】
バインダ樹脂１８としては、たとえばポリカーボネート、ポリメチルメタクリレート、ポリスチレンおよびポリ塩化ビニルなどのビニル重合体、その共重合体、ポリエステル、ポリエステルカーボネート、ポリアリレート、ポリスルホン、ポリイミド、フェノキシ樹脂、エポキシ樹脂、ならびに、シリコーン樹脂などが挙げられ、これらの部分的架橋硬化物も使用できる。
【００６９】
前述の電荷輸送物質９がバインダ樹脂１８に結着した形で電荷輸送層６が形成される。バインダ樹脂１８と電荷輸送物質９の割合は、バインダ樹脂１００重量部に対して３０〜２００重量部が好ましく、より好ましくは４０〜１５０重量部の範囲で使用される。なお電荷輸送層６には、成膜性、可とう性、塗布性などを向上させるために周知の可塑剤、酸化防止剤、紫外線吸収剤、レベリング剤などの添加剤を含有させても良い。電荷輸送層６は、前述の電荷輸送物質９およびバインダ樹脂１８などを用いて、電荷発生層用塗布液と同様にして調製された電荷輸送層用塗布液を、電荷発生層５と同様の装置を用いて電荷発生層５上に塗布することによって形成される。
【００７０】
電荷輸送層６の膜厚は、５〜５０μｍが好ましく、より好ましくは１０〜４５μｍである。
【００７１】
単層型電子写真感光体の感光層１４は、導電性支持体２上に、前記特定のフタロシアニンを電荷発生物質８として、電荷輸送物質９とともに含有して構成される。感光層１４の形成方法としては、単層型感光体の電荷輸送層用塗布液と同様の配合比の液に、電荷発生物質８として、前記特定の結晶性フタロシアニン組成物が分散された感光層用塗布液を用いる方法がある。その場合、前記特定の結晶性フタロシアニン組成物の粒径は、充分小さいことが必要で、好ましくは１μｍ以下である。感光層１４内に分散される電荷発生物質８の量は、過少では感度不足、過多では帯電性低下および感度低下を誘発するなどの弊害があり、０．５〜５０重量％が好ましく、より好ましくは１〜２０重量％で使用される。単層型感光体の感光層１４にも、成膜性、可撓性および機械的強度などを改善するため、従来公知の可塑剤、残留電位を抑制するための添加剤、分散安定向上のための分散補助剤、塗布性を改善するためのシリコーンオイルおよびフッ素系オイルなどのレベリング剤、界面活性剤、その他の添加剤が加えられても良い。
【００７２】
感光層１４の膜厚は５〜４０μｍ、好ましくは１５〜３０μｍで使用される。導電性支持体２と感光層４または１４との間には、中間層である下引き層が設けられていてもよい。中間層としては、たとえばアルミニウム陽極酸化被膜、酸化アルミニウムおよび水酸化アルミニウムなどの無機層、または、ポリビニルアルコール、カゼイン、ポリビニルピロリドン、ポリアクリル酸、セルロース類、ゼラチン、デンプン、ポリウレタン、ポリイミドおよびポリアミドなどの有機層を用いることができる。下引き層は、これらの材料を含有する下引き層用塗布液を、前記導電性支持体２上に塗布して形成される。
【００７３】
これらのうちポリアミド樹脂がより好ましい。その理由は、バインダ樹脂の特性として、下引き層上に感光体層を形成する際に用いられる溶媒に対して溶解や膨潤などが起こらないこと、導電性支持体との接着性に優れること、可撓性を有すること、および原価を低く抑えることができることなどの条件が必要とされるからである。ポリアミド樹脂のうち、特に好ましくは、アルコール可溶性ナイロン樹脂を用いることができる。たとえば、６−ナイロン、６６−ナイロン、６１０−ナイロン、１１−ナイロンおよび１２−ナイロンなどを共重合させた、いわゆる共重合ナイロンや、Ｎ−アルコキシメチル変性ナイロンおよびＮ−アルコキシエチル変性ナイロンのように、ナイロンを化学的に変性させたタイプなどがある。
【００７４】
また、これらの中間層には、アルミニウム、銅、錫、亜鉛およびチタンなどの金属または金属酸化物など、導電性または半導電性の微粒子を含んでいてもよい。
【００７５】
下引き層用塗布液に使用される有機溶剤としては、一般的な有機溶剤を使用することができる。特に、下引き層のバインダ樹脂として、特に好ましいアルコール可溶性ナイロン樹脂を用いる場合には、炭素数１〜４の低級アルコール群と、該低級アルコール以外の有機溶剤、たとえばジクロロメタン、クロロホルム、１，２−ジクロロエタン、１，２−ジクロロプロパン、トルエン、テトラヒドロフランおよび１，３−ジオキソランなどから成る群とから選ばれた単独系または混合系の有機溶媒であることが好ましい。前記低級アルコール以外の有機溶剤を混合することにより、アルコール系溶剤単独よりも酸化チタンの分散性が改善され、塗布液の保存安定性の長期化や塗布液の再生が可能となる。また、下引き層用塗布液中に導電性支持体を浸漬塗布して下引き層を形成する際、下引き層の塗布欠陥やムラを防止し、その上に形成される感光層が均一に塗布できるので、膜欠陥のない非常に優れた画像特性を有する電子写真感光体を作製することができる。
【００７６】
中間層の膜厚は、０．０１〜２０μｍが好ましく、より好ましくは０．０５〜１０μｍの範囲である。下引き層の膜厚が０．０１μｍより薄ければ実質的に下引き層として機能しなくなり、導電性支持体２の欠陥を被覆して均一な表面性が得られず、導電性支持体２からの電荷の注入を防止することができなくなり、帯電性の低下が生じる。２０μｍよりも厚くすることは下引き層を浸漬塗布する場合、感光体を製造する上で難しくなり感光体の感度が低下する。
【００７７】
前記バインダ樹脂および金属酸化物などが、前述の有機溶剤に分散されて、下引き層用塗布液が調製される。下引き層用塗布液の分散方法としては、ボールミル、サンドミル、アトライタ、振動ミルおよび超音波分散機などによる方法がある。下引き層用塗布液の塗布方法としては、前述の浸漬塗布法などの一般的な方法が適用できる。
【００７８】
積層型および単層型のいずれの感光体においても、感光層４または１４上に、必要であれば感光層表面を保護するために保護層を設けてもよい。表面保護層には、熱可塑性樹脂、および、光または熱硬化性樹脂を用いることができる。保護層中に、紫外線吸収剤、酸化防止剤、金属酸化物などの無機材料、有機金属化合物、および電子受容性物質などを含有させても構わない。また、保護層には、感光層と同様、必要に応じて、二塩基酸エステル、脂肪酸エステル、リン酸エステル、フタル酸エステルおよび塩素化パラフィンなどの可塑剤を混合させて、加工性および可塑性を付与して機械的物性の改良を施してもよく、レベリング剤などの添加剤を混合しても構わない。
【００７９】
図４は、本発明による電子写真感光体を搭載したレーザプリンタ３０を示す構成図である。電子写真装置であるレーザプリンタ３０は、感光体１００、半導体レーザ３１、コロナ帯電器３６、現像器３７、転写帯電器４１、分離帯電器４２、定着器４４、排紙トレイ４５およびクリーナ４６とを含んで構成される。レーザプリンタ３０では、コロナ帯電器３６によって感光体１００の表面をマイナス極性に均一に帯電させ、半導体レーザ３１で画像情報に基づいて光照射して像露光を行い、感光体１００を回転させて露光領域を現像装置と対向する現像領域に到達させ、露光領域にマイナス帯電されたトナーを付着させて現像する反転現像方式を採用する。
【００８０】
このような半導体レーザや発光ダイオード（ＬＥＤ）を露光光源として用いる電子写真装置において、前記特定の結晶性フタロシアニン組成物を含有する電子写真感光体を搭載することによって、これらの露光光源により照射され周辺部に広がった弱い光に対しては感光せず、ドットが広がることがなく、より良好な潜像形成ができるので、高画質を得ることができる。
【００８１】
このような反転現像プロセスを用いて画像を形成する場合には、露光部の表面電荷が減少した部分にトナー像が形成されることから、露光以外の要因で表面電荷が減少すると白地にトナーが付着する黒ポチなどの画像のカブリが発生し、著しい画質劣化を生じる。これは、導電性支持体や感光層の欠陥に起因して微小な領域での帯電性の低下を招くことにより、白地に黒点が発生するなど著しい画像欠陥となる。しかし、前述のようにして下引き層を形成する電子写真感光体においては、塗布欠陥やムラのない非常に均一な感光層の塗布膜を形成することができる。したがって、前記電子写真感光体を搭載すれば、露光以外の要因で表面電荷が減少することがなく、白地にトナーが付着する黒ポチの発生がなく、高感度、高画質および高解像度のすべてを満足する、デジタルデータの出力に適した複写機、プリンタおよびファクシミリなどの電子写真装置を提供することができる。
【００８２】
【実施例】
以下に実施例を挙げて、本発明による電子写真感光体およびそれを用いた電子写真装置を具体的に説明するが、その趣旨を超えない限り以下の実施例に限定されるものではない。
【００８３】
(製造例１)
ｏ−フタロジニトリル４０ｇと、四塩化チタン１８ｇと、α−クロロナフタレン５００ｍｌとを窒素雰囲気下２００〜２５０℃で３時間加熱撹拌して反応させ、１００〜１３０℃まで放冷後、熱時濾過し、１００℃に加熱したα−クロロナフタレン２００ｍｌで洗浄してジクロロチタニウムフタロシアニン粗生成物を得た。この粗生成物を室温にてα−クロロナフタレン２００ｍｌ、ついでメタノール２００ｍｌで洗浄後、さらにメタノール５００ｍｌ中で１時間熱懸洗を行った。濾過後、得られた粗生成物を水５００ｍｌ中で、ｐＨが６〜７になるまで熱懸洗を繰返した後、乾燥してチタニルフタロシアニン結晶を得た。
【００８４】
得られた結晶に無金属フタロシアニンを加えて１,３−ジオキソランに混合し、ペイントコンディショナ装置（レッドレベル社製）により直径２ｍｍのガラスビーズと共にミリング処理し、メタノールで洗浄した後、乾燥し、本発明における特定の結晶性フタロシアニン組成物を得た。
【００８５】
得られた結晶性フタロシアニン組成物について、以下の条件でＸ線回折スペクトルを測定した。なお後述する実施例５で用いる結晶性フタロシアニンについても、同様の条件で測定した。
Ｘ線源 ＣｕＫα＝１．５４Å
電圧 ３０〜４０ｋＶ
電流 １００ｍＡ
スタート角度 ５．０゜
ストップ角度 ３０．０゜
ステップ角度 ０．０１〜０．０２゜
測定時間 ２．０〜０．５゜／ｍｉｎ．
測定方法 θ／２θ スキャン方法
【００８６】
得られた結晶性フタロシアニン組成物は、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．０°、９．０°、１４．１°、１８．０°、２３．７°および２７．２°に主要なピークを示す、チタニルフタロシアニンと無金属フタロシアニンとから成る結晶性フタロシアニン組成物であった。
【００８７】
（実施例１）
製造例１で作製された結晶性フタロシアニン組成物０．９重量部とχ型無金属フタロシアニン（大日本インキ社製Fastogen Blue ８１２０ＢＳ）０．９重量部とブチラール樹脂（積水化学社製ＢＬ−１）１．２重量部とを、１，３−ジオキソラン９７重量部に混合してペイントシェーカにて分散処理して電荷発生層用塗布液を調製した。なお、前記χ型無金属フタロシアニンは、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．６°、９．０°、１６．８°、１７．３°および２２．３°に主要なピークを示す。調製した電荷発生層用塗布液の結晶性フタロシアニン組成物をＸ線回折スペクトル測定したところ、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．０°、７．６°、９．０°、１３．６°、１６．８°および２７．２°にピークを持つＸ線回折スペクトルを示した。この電荷発生層用塗布液を図３に示したような浸漬塗布装置の塗布槽１３に満たし、導電性支持体として直径３０ｍｍ、全長３２６．３ｍｍのアルミニウム製のドラム状支持体を浸漬して引き上げ、自然乾燥して膜厚０．５μｍの電荷発生層を形成した。
【００８８】
下記構造式（５）で示されるスチリル化合物１０重量部と、下記構造式（６）で示される繰返し単位を有するポリカーボネート樹脂(三菱ガス化学社製ＰＣＺ４００)１６重量部とを混合し、ＴＨＦを溶剤として固形分２１重量％の電荷輸送層用塗布液を調製した。調製した電荷輸送層用塗布液を、電荷発生層用塗布液と同様にして電荷発生層上に塗布し、１１０℃にて１時間乾燥し、膜厚２２μｍの電荷輸送層を形成した。
以上のようにして、積層型電子写真感光体を作製した。
【００８９】
【化９】

【００９０】
【化１０】

【００９１】
（実施例２）
製造例１で作製された結晶性フタロシアニン組成物を１．８重量部とブチラール樹脂（積水化学社製ＢＬ−１）１．２重量部とを、１，３−ジオキソラン９７重量部に混合してペイントシェーカにて分散処理して電荷発生層用塗布液Ａを得た。
【００９２】
また、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．６°、９．０°、１６．８°、１７．３°および２２．３°に主要なピークを持つχ型無金属フタロシアニン（大日本インキ社製Fastogen Blue ８１２０ＢＳ）１．８重量部と、ブチラール樹脂（積水化学社製ＢＬ−１）１．２重量部とを、１，３−ジオキソラン９７重量部に混合してペイントシェーカにて分散処理して電荷発生層用塗布液Ｂを得た。
【００９３】
これら２つの電荷発生層用塗布液ＡおよびＢを重量比でＡ：Ｂ＝６０：４０の比率に混合した塗布液を、直径３０ｍｍ、全長３２６．３ｍｍのアルミニウム製ドラム状の導電性支持体上に浸漬塗布した後、自然乾燥して膜厚０．５μｍの電荷発生層を形成した。
【００９４】
図５は、本発明の実施例２で得られた結晶性フタロシアニン組成物のＸ線回折スペクトルを示す図である。電荷発生層用塗布液AおよびBを混合した塗布液（A：B＝６０：４０）の結晶性フタロシアニン組成物をＸ線回折スペクトル測定したところ、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．０°、７．６°、９．０°、１３．６°、１６．８°および２７．２°にピークを持つＸ線回折スペクトルを示した。
【００９５】
次いで、下記構造式（７）で示されるビスアミン化合物１０重量部と、前記構造式（６）で示される繰返し単位を有するポリカーボネート樹脂(三菱ガス化学社製：ＰＣＺ４００)１６重量部とを混合し、ＴＨＦを溶剤として固形分２１重量％の電荷輸送層用塗布液を調製した。電荷輸送層用塗布液を、先に形成した電荷発生層上に塗布し、１１０℃にて１時間乾燥して膜厚２２μｍの電荷輸送層を形成した。
以上のようにして積層型感光体を作製した。
【００９６】
【化１１】

【００９７】
（実施例３）
実施例２で調製した電荷発生層用塗布液ＡおよびＢを重量比でＡ：Ｂ＝９０：１０の比率に混合した塗布液として用いた以外は、実施例２と同様にして感光体を作製した。
【００９８】
（実施例４）
実施例２で調製した電荷発生層用塗布液ＡおよびＢを重量比でＡ：Ｂ＝３０：７０の比率に混合した塗布液として用いた以外は、実施例２と同様にして感光体を作製した。
【００９９】
（実施例５）
実施例２で使用した電荷発生層用塗布液ＡおよびＢを重量比でＡ：Ｂ＝６０：４０の比率に混合した後、さらにペイントシェーカにて共分散して得られた結晶性フタロシアニン組成物を含有する電荷発生層用塗布液を調製した。調製した電荷発生層用塗布液を実施例２と同様にして導電性支持体上に浸漬塗布し、自然乾燥により膜厚０．５μｍの電荷発生層を形成した。さらに実施例２と同様にして電荷輸送層を形成し、感光体を作製した。
【０１００】
図６は、本発明の実施例５で得られた結晶性フタロシアニン組成物のＸ線回折スペクトルを示す図である。電荷発生層用塗布液AおよびBを混合した塗布液（A：B＝６０：４０）を共分散して得られた塗布液の結晶性フタロシアニン組成物をＸ線回折スペクトル測定したところ、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて少なくともブラッグ角（２θ±０．２°）で７．０°、７．６°、９．０°、１３．６°、１６．８°および２７．２°に主要なピークを有し、７．０°に対する１６．８°のピークの高さが２倍よりも小さいＸ線回折スペクトルを示した。
【０１０１】
（比較例１）
実施例２で調製した電荷発生層用塗布液Ａを用いて電荷発生層を形成した以外は、実施例２と同様にして感光体を作製した。
【０１０２】
（比較例２）
実施例２で調製した電荷発生層用塗布液Ｂを用いて電荷発生層を形成した以外は、実施例２と同様にして感光体を作製した。
【０１０３】
（評価１）
実施例１〜５、比較例１および２で作製した電子写真感光体を、市販の反転現像プロセスを採用した複写機（シャープ社製ＡＲ−Ｎ２００）を１２００ｄｐｉ相当のドットが出力できるように改造した実験機に搭載し、解像度を検討した。パソコンにて黒ベタに白１ドットを書かせたデータ（レーザを全面走査し１ドットのみオフとするデータ）を作製し、このデータをプリンタインタフェースを介し、前記実験機に送信して２５℃／６０％ＲＨの常温常湿下（以下、「Ｎ／Ｎ環境」と称する）にてプリントアウトされた出力画像を観察した。Ｎ／Ｎ環境下で出力した画像について解像度（Ｎ／Ｎ解像度）を評価した。また、前記実験機を５℃／２０％ＲＨの低温低湿環境下（以下、「Ｌ／Ｌ環境」と称する）にて黒べた画像を出力した。Ｌ／Ｌ環境下で出力した黒べた画像について感度（Ｌ／Ｌ感度）を評価した。さらに、３５℃／８５％ＲＨの高温高湿環境下（以下、「Ｈ／Ｈ環境」と称する）にて白べた画像を出力した。Ｈ／Ｈ環境下で出力した白べた画像について画質（Ｈ／Ｈ画像）を評価した。
以上の評価結果を表４に示す。
【０１０４】
【表４】

【０１０５】
表４から、いずれの実施例についても、Ｎ／Ｎ解像度は、黒ベタ上に１ドットの白点がはっきりと確認できた。このことから、本発明による感光体は充分な高解像度画像を出力できることが判った。また、いずれの実施例についても、Ｌ／Ｌ感度は、画像濃度低下のない良好な画像が得られた。Ｈ／Ｈ画像は、実施例１〜３で若干の黒ポチが発生したが、いずれも実使用上大きな問題になるほどではなく、充分な高解像度画像を出力できることが判った。比較例１は、ドットを出力させるデータを送信したにも関わらず、出力された画像は黒べたとなり、ドットが正確に形成されていないことが判った。比較例２は、出力された画像のドットがみだれて黒べた濃度が低下していた。
【０１０６】
以上の結果より、導電性支持体上に設けられた感光層中に、特定の結晶型を有する電荷発生物質を含有する電荷発生層を形成することによって、解像度を維持しながらＨ／Ｈ環境下での黒ポチを抑制し、Ｌ／Ｌ環境下での感度低下を防止することができる。すなわち、高感度、高画質および高解像度をすべて満足する電子写真感光体を作製することができる。
【０１０７】
（実施例６）
実施例２で用いたビスアミン化合物の代わりに、下記構造式（８）で示されるブタジエン化合物を用いた以外は、実施例２と同様にして電子写真感光体を作製した。
【０１０８】
【化１２】

【０１０９】
（実施例７）
実施例５で用いたビスアミン化合物の代わりに、前記構造式（８）で示されるブタジエン化合物を用いた以外は、実施例５と同様にして電子写真感光体を作製した。
【０１１０】
（比較例３）
比較例１で用いたビスアミン化合物の代わりに、前記構造式（８）で示されるブタジエン化合物を用いた以外は、比較例１と同様にして電子写真感光体を作製した。
【０１１１】
（比較例４）
比較例２で用いたビスアミン化合物の代わりに、前記構造式（８）で示されるブタジエン化合物を用いた以外は、比較例２と同様にして電子写真感光体を作製した。
【０１１２】
（評価２）
実施例６、７、比較例３および４で作製した電子写真感光体の光減衰特性の測定を行った。
ドラム感度試験機（Ｇｅｎｔｅｃ社製）を用いて、電子写真感光体の表面をスコロトロンチャージャで、−６００±２０Ｖに帯電させて、露光光源である半導体レーザ光（波長７８０ｎｍ）の光強度をＮＤフィルタで調整して感光体の表面に照射し、各光強度のおける表面電位を測定した。
【０１１３】
図７および図８は、本発明の実施例および比較例の電子写真感光体における光減衰特性を示す図である。
【０１１４】
実施例６の感光体の光減衰特性は、図７の感光体Ａに示すように弱い露光に対しては光減衰が小さく、強い露光に対しては充分に光減衰していることが判った。実施例７の感光体の光減衰特性は、図７の感光体Ｂに示すように弱い露光に対しては光減衰が小さく、強い露光に対しては完全に光減衰しており、実施例６よりさらに感度が向上していることが判った。比較例３の感光体の光減衰特性は、図７の感光体Ｃに示すように弱い露光でも光減衰が大きいことが判った。また、比較例３の感光体について、評価１と同様にして黒ベタに白１ドットを書かせたデータを出力した画像を検討したところ、ドットを出力させるデータを送ったにもかかわらず、出力された画像は黒ベタとなり、ドットが正確に形成されていないことが判明した。比較例４の光減衰特性感光体は、図７の感光体Ｄに示すように強い露光でも光減衰が不充分であり、残留電位が大きいことが判った。また、比較例４の感光体について、評価１と同様にして黒ベタに白１ドットを書かせたデータを出力した画像を検討すると、出力された画像のドットは判別可能だが、黒ベタ部分の濃度が低くなっていた。
【０１１５】
（実施例８）
製造例１で作製した結晶性フタロシアニン組成物１０重量部とχ型無金属フタロシアニン（大日本インキ社製Fastgen Blue ８１２０ＢＳ）５重量部とを１，３−ジオキソラン１８５重量部に混合しペイントシェーカにて分散処理した後、前記構造式（８）で示されるブタジエン化合物１００重量部と、ポリカーボネート樹脂（三菱ガス化学社製ＰＣＺ４００）１６０重量部とを混合し、ＴＨＦを溶剤として固形分２１重量％の塗布液を調製した。この塗布液を塗布槽に満たし、導電性支持体として直径３０ｍｍ、全長３２６．３ｍｍのアルミニウム製のドラム状支持体を浸漬して引き上げ、１１０℃で１時間乾燥して膜厚２０μｍの感光層１４を形成し、単層型感光体を作製した。
【０１１６】
（実施例９）
実施例５で用いたビスアミン化合物の代わりに、下記構造式（９）で示されるヒドラゾン化合物を用いた以外は、実施例５と同様にして電子写真感光体を作製した。
【０１１７】
【化１３】

【０１１８】
（比較例５）
比較例１で用いたビスアミン化合物の代わりに、前記構造式（９）で示されるヒドラゾン化合物を用いた以外は、比較例１と同様にして電子写真感光体を作製した。
【０１１９】
（比較例６）
比較例２で用いたビスアミン化合物の代わりに、前記構造式（９）で示されるヒドラゾン化合物を用いた以外は、比較例２と同様にして電子写真感光体を作製した。
【０１２０】
（評価３）
実施例８で作製した電子写真感光体を、市販の反転現像プロセスを採用した複写機（シャープ社製ＡＲ−Ｎ２００）を１２００ｄｐｉ相当のドットが出力できるように改造し、さらに正帯電プロセスに改造した実験機に搭載し、解像度を検討した。パソコンにて黒ベタに白１ドットを書かせたデータ（レーザを全面走査し１ドットのみオフとするデータ）を作製し、このデータをプリンタインタフェースを介し、前記実験機に送信してプリントアウトされた出力画像を観察した。また、実施例９、比較例５および６の感光体の光減衰特性について、評価２と同様にして測定した。
【０１２１】
実施例８の感光体については、黒ベタ上に１ドットの白点がはっきりと確認できた。実施例８の感光体は充分な高解像度画像を出力できることが判った。実施例９の感光体の光減衰特性は、図８の感光体Ｅに示すように弱い露光に対しては光減衰が小さいが、強い露光に対しての光減衰はやや頭打ちになっており、比較例５からの感度向上は少ないことが判った。比較例５の感光体の光減衰特性は、図８の感光体Ｆに示すように弱い露光でも光減衰が大きいことが判った。比較例５の感光体について画像を検討したところ、ドットを出力させるデータを送ったにもかかわらず、出力された画像は黒ベタとなっており、ドットがきちんと形成されていないことが判明した。比較例６の感光体の光減衰特性は、図８の感光体Ｇに示すように強い露光でも光減衰が不充分であり、残留電位が大きいことが判った。比較例６の感光体について画像を検討すると、出力された画像のドットは判別可能だが、黒ベタ部分の濃度が低くなっていた。
【０１２２】
以上の結果より、特定の結晶性フタロシアニン組成物を含有する感光層を設けることによって、小さな露光エネルギに対しても高感度である感光体（比較感光体ＣおよびＦ）ではなく、弱い露光には光減衰が少なく、強い露光に対して高感度で、完全に電位減衰する、露光エネルギに対しリニアに応答する高感度な感光体（感光体ＡおよびＢ）を提供することができる。
【０１２３】
また、感光体Ｅよりも感光体Ａのほうがより強い露光エネルギに対しても高感度であることから、本発明において目的とする効果は、特定の高移動度を有する電荷輸送材料によって発揮されることがわかる。すなわち、該電荷輸送物質によって、高感度、高画質および高解像度のすべてをより満足する電子写真感光体を作製することができる。
【０１２４】
【発明の効果】
本発明によれば、感光層中に、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、少なくとも７．０°、９．０°、１４．１°、１８．０°、２３．７°および２７．２°に主要なピークを持つ、チタニルフタロシアニンと無金属フタロシアニンとから成る組成物と、ＣｕＫα特性Ｘ線（波長：１．５４Å）に対するＸ線回折スペクトルにおいて、ブラッグ角（２θ±０．２°）で、少なくとも７．６°、９．０°、１６．８°、１７．３°および２２．３°に主要なピークを持つχ型無金属フタロシアニンとから成り、前記特定のＸ線回折スペクトルを有する結晶性フタロシアニン組成物を電荷発生物質として用いることによって、弱い露光には光減衰が少なく、強い露光に対して高感度で、完全に電位減衰し、露光エネルギに対しリニアに応答する高感度な感光体を得ることができる結果、高感度、高画質および高解像度のすべてを満足する電子写真感光体を提供することができる。
【０１２５】
また本発明によれば、半導体レーザや発光ダイオード（ＬＥＤ）を露光光源として用い、反転現像プロセスを用いる電子写真装置において、前記電子写真感光体を搭載することによって、高感度、高画質および高解像度のすべてを満足する電子写真装置を提供することができる。
【図面の簡単な説明】
【図１】積層型の電子写真感光体の構成例を示す断面図である。
【図２】単層型の電子写真感光体の構成例を示す断面図である。
【図３】浸漬塗布法において用いる浸漬塗布装置の一例を示す構成図である。
【図４】本発明による電子写真感光体を搭載したレーザプリンタ３０を示す構成図である。
【図５】本発明の実施例２で得られた結晶性フタロシアニン組成物のＸ線回折スペクトルを示す図である。
【図６】本発明の実施例５で得られた結晶性フタロシアニン組成物のＸ線回折スペクトルを示す図である。
【図７】本発明の実施例および比較例の電子写真感光体における光減衰特性を示す図である。
【図８】本発明の実施例および比較例の電子写真感光体における光減衰特性を示す図である。
【符号の説明】
２ 導電性支持体
４，１４ 感光層
５ 電荷発生層
６ 電荷輸送層
７ バインダ樹脂
８ 電荷発生物質
９ 電荷輸送物質
１９ バインダ樹脂[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic photosensitive member having high resolution, high sensitivity, and high image quality, and an electrophotographic apparatus using the same.
[0002]
[Prior art]
C. F. The electrophotographic technology invented by Carlson has been used not only in the field of copiers but also in the fields of various printers and facsimiles in recent years, because it is possible to obtain images that are immediate, high quality and highly storable. Extensive.
[0003]
For photoconductors that are the core of electrophotographic technology, inorganic photoconductive materials such as Se, As-Se alloys, CdS and ZnO have been used as photoconductive materials. Therefore, a photoconductor using an organic photoconductive material has been developed, which has advantages not seen in inorganic photoconductive materials, such as being able to reduce manufacturing costs because of its ease of manufacturing. In the photoreceptor using such an organic photoconductive material, a charge generation layer composed of a substance having a high charge generation function and a charge transport layer composed of a substance having a high charge transport function are laminated. There is a so-called laminated type photoreceptor. The laminated photoconductor has a wide range of material selection because of its limited function in each layer, high safety, high sensitivity, and high productivity because it can be manufactured by coating. It is also advantageous in terms of cost. For these reasons, the multilayer photoconductors are currently produced in large quantities as the mainstream of photoconductors.
[0004]
In recent years, with the digitization of image information, the photosensitive layer is exposed by semiconductor laser light or LED array light using a semiconductor laser or LED (Light Emitting Diode) array as an exposure light source instead of conventional white light, respectively. Recording of image information is performed. Currently, near-infrared light of 780 nm and red light source of 650 nm are most often used as exposure light sources for the photosensitive layer.
[0005]
Digitized image information is recorded on a photoconductor by computer output information converted into an optical signal when the image information is directly used as computer output, and an original image is input as information. After an image of a document is read as optical information and converted into a digital electric signal, it is converted again into an optical signal and recorded on the photosensitive member by the optical signal. In any case, the image information is recorded on the photosensitive layer by a minute light spot irradiated to the photosensitive layer from an optical recording head and a recording optical system, and the portion irradiated with the light spot on the photosensitive layer is the toner. The image is made visible by being developed. An image is represented by a collection and arrangement of minute dots called pixels developed by toner. Therefore, in an optical recording head, a recording optical system, and the like, since image information is recorded at a high density, higher resolution is being promoted so that as small a spot as possible can be formed.
[0006]
For optical systems that record image information on the photosensitive layer, variable spot laser recording (O plus E May 1996), multi-laser beam recording, and ultra-precision and ultra-high-speed polygon mirrors (Japan Hardcopy '96 papers) ) Etc. have been developed. As a result, at present, image information can be recorded on the photosensitive layer at a recording density of 1200 dpi (dotper inch: number of dots per inch) or more by an optical system. Even if an optical system for recording image information on the photosensitive layer at a high density is developed, it is not always easy to record the image information on the photosensitive layer as an electrostatic latent image with high reproducibility. This is because the laser light has a characteristic that the light intensity distribution shows a Gaussian distribution that is stronger at the center and spreads at the periphery. In the conventional high-sensitivity electrophotographic photosensitive member, since the light spread to the peripheral portion is also exposed and developed, it is difficult to improve the image quality by spreading the dots.
[0007]
Conventionally, organic materials having sensitivity to long-wavelength light as described above include methacrylic squaric dyes, indoline dyes, cyanine dyes, bililium dyes, polyazo dyes, phthalocyanine dyes, and naphthoquinone dyes. Dyes are known. Squalic acid methine dyes, indoline dyes, cyanine dyes, and bilium dyes can be increased in wavelength, but lack practical stability such as repetitive characteristics, and polyazo dyes are difficult to increase in wavelength and are However, the naphthoquinone system is difficult in terms of sensitivity.
[0008]
Among the phthalocyanine dyes, in a photoreceptor using a metal phthalocyanine compound, the sensitivity peak varies depending on the central metal, but it is known that all of them are on the relatively long wavelength side of 700 to 750 nm. In recent years, research on oxotitanyl phthalocyanine, which exhibits high sensitivity among these phthalocyanines, has been vigorously conducted. As described in Journal of Electrophotographic Society, Vol. 32, No. 3, p282, oxotitanyl phthalocyanine alone is classified into a number of crystal types based on the difference in diffraction angle of the X-ray diffraction spectrum.
[0009]
An electrophotographic photoreceptor using two or more kinds of phthalocyanines has been studied for the purpose of increasing the sensitivity in the vicinity of 780 mn, which is the emission wavelength of the semiconductor laser. Japanese Patent No. 2780295 proposes a mixed crystal of oxotitanyl phthalocyanine and metal-free phthalocyanine, and Japanese Patent Registration No. 2754739 proposes a photoreceptor using a composition of oxotitanyl phthalocyanine and metal-free phthalocyanine. However, since these high-sensitivity photosensitive members are also sensitive to weak exposure, they are exposed to light that has spread to the periphery as described above and are developed, so that high resolution is achieved. I can't. In addition, as a photoreceptor in which two kinds of phthalocyanines are mixed, Japanese Patent No. 3005052 proposes a photoreceptor in which a specific crystalline oxotitanyl phthalocyanine and a metal-free phthalocyanine are mixed, and has a slight resolution improvement effect. However, it is still insufficient.
[0010]
[Problems to be solved by the invention]
As a means to achieve high resolution, a low-sensitivity photoconductor is used, and as described above, the sensitivity to the light around the laser beam is reduced and only the strong light at the center is exposed to form faithful dots. It is. According to such means, a low-speed printer is sufficient, but in the progress of high-speed operation, since the photoconductor is low in sensitivity, a high-power semiconductor laser is required. Has a problem that the image density is remarkably increased and the image density is lowered in the reversal development process. Thus, the present situation is that both high sensitivity and high resolution cannot be achieved.
[0011]
In particular, in a photoconductor used in an electrophotographic apparatus that forms an image by a reversal development process, if the charge on the surface of the photoconductor decreases due to factors other than exposure, defects caused by fogging called black spots, which are minute black spots, occur. Since the image quality deteriorates, an undercoat layer is provided to reduce such image defects. Specifically, as a charge blocking layer between a conductive support and a photosensitive layer, there are a photoreceptor in which the surface of a conductive support is oxidized to form an alumite layer, and a photoreceptor in which an undercoat layer is formed. A photoreceptor having an alumite layer has a problem that productivity is deteriorated because the conductive support is oxidized and the cost is increased. Yes. However, even when the undercoat layer is formed, there is a problem that the sensitivity of the photoreceptor is lowered.
[0012]
As described above, the conventionally known photoreceptors still have insufficient characteristics to achieve high sensitivity, high image quality, and high resolution, and further improvements are desired.
[0013]
The object of the present invention satisfies all of high sensitivity, high image quality and high resolution.
An electrophotographic photosensitive member and an electrophotographic apparatus using the same are provided.
[0014]
[Means for Solving the Problems]
  The present invention is an electrophotographic photosensitive member having a conductive support and a photosensitive layer formed on the conductive support,
  The photosensitive layer has an Bragg angle (2θ ± 0.2 °) of at least 7.0 °, 7.6 °, 9.0 ° in an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54Å), Contains crystalline phthalocyanine composition with peaks at 13.6 °, 16.8 ° and 27.2 °And
  The crystalline phthalocyanine composition is
  In the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54Å), at least 7.0 °, 9.0 °, 14.1 °, 18.0 ° at Bragg angle (2θ ± 0.2 °) A composition comprising titanyl phthalocyanine and metal-free phthalocyanine having major peaks at 23.7 ° and 27.2 °;
  In an X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54１．５), at least 7.6 °, 9.0 °, 16.8 °, 17.3 ° at a Bragg angle (2θ ± 0.2 °) And χ-type metal-free phthalocyanine with a major peak at 22.3 °An electrophotographic photosensitive member characterized by the above.
[0015]
  According to the invention, in the photosensitive layerIn the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54 Å), at Bragg angle (2θ ± 0.2 °), at least 7.0 °, 9.0 °, 14.1 °, 18.0 In an X-ray diffraction spectrum for a composition composed of titanyl phthalocyanine and metal-free phthalocyanine having major peaks at °, 23.7 ° and 27.2 °, and CuKα characteristic X-ray (wavelength: 1.54Å), Χ-type metal-free phthalocyanine with major peaks at an angle (2θ ± 0.2 °) of at least 7.6 °, 9.0 °, 16.8 °, 17.3 ° and 22.3 ° ,By using the crystalline phthalocyanine composition having the specific X-ray diffraction spectrum as a charge generating material, light attenuation is small for weak exposure, high sensitivity to strong exposure, complete potential attenuation, and exposure energy. On the other hand, as a result of obtaining a highly sensitive photoconductor that responds linearly, an electrophotographic photoconductor satisfying all of high sensitivity, high image quality and high resolution can be provided.
[0016]
According to the present invention, the crystalline phthalocyanine composition has a Bragg angle (2θ ± 0.2 °) of 16 ° with respect to 7.0 ° in an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54Å). .8 ° peak height ratio is less than twice.
[0017]
According to the present invention, in the specific X-ray diffraction spectrum, by using a crystalline phthalocyanine composition having a specific peak intensity as a charge generating material, the potential can be attenuated more completely with respect to strong exposure. As a result of obtaining a photoconductor, an electrophotographic photoconductor that satisfies all of high sensitivity, high image quality, and high resolution can be provided.
[0022]
  In the present invention, the χ-type metal-free phthalocyanine isSaidThe crystalline phthalocyanine composition contains 10 to 70% by weight.
[0023]
According to the present invention, when the content of the χ-type metal-free phthalocyanine is specified, dots cannot be accurately formed at less than 10% by weight, and high resolution and high image quality cannot be obtained, or when the content exceeds 70% by weight. An electrophotographic photosensitive member satisfying all of high sensitivity, high image quality, and high resolution can be provided without dots appearing and black solid density being lowered and high resolution and high sensitivity not being obtained.
[0024]
In the present invention, the photosensitive layer contains a butadiene compound represented by the following general formula (1) as a charge transport material.
[0025]
[Chemical Formula 3]

[0026]
(Wherein R₁~ R_FourRepresents an aryl group which may have a substituent or an aralkyl group which may have a substituent. )
[0027]
According to the present invention, since a specific butadiene compound is used as a charge transport material, the electrophotographic photosensitive member satisfies all of high sensitivity, high image quality and high resolution since it has very high mobility. Can do.
[0028]
In the invention, the photosensitive layer contains a bisamine compound represented by the following general formula (2) as a charge transport material.
[0029]
[Formula 4]

[0030]
(Wherein R_FiveAnd R₆Each represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, an alkoxycarbonyl group, or an amino group which may have a substituent. R₇Represents an alkyl group or an alkoxy group. )
[0031]
According to the present invention, by using a specific bisamine compound as a charge transport material, an electrophotographic photosensitive member that satisfies all of high sensitivity, high image quality, and high resolution since it has very high mobility. Can do.
[0032]
In the invention, it is preferable that the photosensitive layer is formed by laminating at least a charge generation layer containing the crystalline phthalocyanine composition as a charge generation material and a charge transport layer containing a charge transport material. .
[0033]
According to the present invention, by using the crystalline phthalocyanine composition having the specific X-ray diffraction spectrum in the charge generation layer as a charge generation material, a multilayer type satisfying all of high sensitivity, high image quality, and high resolution. An electrophotographic photoreceptor can be provided.
[0034]
The present invention also provides an electrophotographic apparatus comprising the above-described electrophotographic photosensitive member, and a semiconductor laser or a light emitting diode that exposes the image to the electrophotographic photosensitive member.
[0035]
According to the present invention, in an electrophotographic apparatus using a semiconductor laser or a light emitting diode (LED) as an exposure light source, by mounting the electrophotographic photoreceptor, weak light that is irradiated by these exposure light sources and spreads in the peripheral portion is obtained. On the other hand, it is not exposed to light, dots do not spread, and a better latent image can be formed, so that high image quality can be obtained.
[0036]
In addition, the present invention is characterized by comprising means for obtaining an image by reversal development of an electrophotographic photoreceptor that has been charged and subjected to image exposure.
[0037]
According to the present invention, in the electrophotographic apparatus using the reversal development process, by mounting the electrophotographic photosensitive member, the surface charge does not decrease due to factors other than the exposure, and the black spots in which the toner adheres to the white background. It is possible to provide an electrophotographic apparatus such as a copying machine, a printer, and a facsimile machine that is suitable for outputting digital data and that is free from occurrence and satisfies all of high sensitivity, high image quality, and high resolution.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below.
[0039]
FIG. 1 is a cross-sectional view illustrating a configuration example of a multilayer electrophotographic photosensitive member. FIG. 2 is a cross-sectional view showing a configuration example of a single layer type electrophotographic photosensitive member. 1, the photosensitive layer 4 is provided on the conductive support 2, and the photosensitive layer 4 includes a charge generation layer 5 containing a charge generation material 8 and a binder resin 7, a charge transport material 9 and a binder resin. It is composed of two layers including a charge transport layer 6 containing 18. 2, the photosensitive layer 14 is provided on the conductive support 2, and the charge transport material 9, the charge generation material 8, and the binder resin 19 are contained in the photosensitive layer 14.
[0040]
The electrophotographic photosensitive member according to the present invention may be either a laminated type as shown in FIG. 1 or a single layer type as shown in FIG. The electrophotographic photosensitive member according to the present invention is characterized in that a specific crystalline phthalocyanine composition is used as the charge generation material 8 in the charge generation layer 5 in the stacked type and in the photosensitive layer 14 in the single layer type.
[0041]
The specific crystalline phthalocyanine composition used as the charge generation material 8 specifically includes a phthalocyanine compound such as a metal phthalocyanine represented by the following general formula (3) and a metal-free phthalocyanine represented by the general formula (4). The specific crystalline phthalocyanine composition may have only one of metal phthalocyanine and metal-free phthalocyanine as long as it exhibits the characteristics in the X-ray diffraction spectrum shown below, and is a composition obtained by mixing these. May be.
[0042]
[Chemical formula 5]

[0043]
[Chemical 6]

[0044]
(In the formulas (3) and (4), X₁~ X_FourEach represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and t, u, v and w each represent an integer of 0 to 4. )
[0045]
The specific crystalline phthalocyanine composition has an Bragg angle (2θ ± 0.2 °) of at least 7.0 ° and 7.6 ° in an X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54１．５). , 9.0 °, 13.6 °, 16.8 ° and 27.2 °, a crystalline phthalocyanine composition {circle around (1)}.
[0046]
The crystalline phthalocyanine composition (1) has a Bragg angle (2θ ± 0.2 °) of 16.8 with respect to 7.0 ° in an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54Å). It is preferable that the crystalline phthalocyanine composition (2) has a peak height ratio of less than 2 times.
[0047]
The crystalline phthalocyanine composition (1) or (2) contains a crystalline phthalocyanine composition (3) composed of titanyl phthalocyanine and metal-free phthalocyanine, and the crystalline phthalocyanine composition (3) is In the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54Å), at least 7.0 °, 9.0 °, 14.1 °, 18.0 ° at Bragg angle (2θ ± 0.2 °) , 23.7 ° and 27.2 °, preferably having major peaks.
[0048]
The crystalline phthalocyanine composition (1) or (2) has an Bragg angle (2θ ± 0.2 °) of at least 7. in an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54 Å). It is more preferable to contain χ-type metal-free phthalocyanine (4) having main peaks at 6 °, 9.0 °, 16.8 °, 17.3 ° and 22.3 °.
[0049]
In particular, it is most preferable that the crystalline phthalocyanine composition (1) or (2) contains both the phthalocyanine composition (3) and the χ-type metal-free phthalocyanine (4).
[0050]
The χ-type metal-free phthalocyanine is preferably contained in the crystalline phthalocyanine composition in an amount of 10 to 70% by weight. If the amount is less than 10% by weight, dots cannot be formed accurately and high resolution and high image quality cannot be obtained. is there.
[0051]
The electrophotographic photosensitive member according to the present invention is constituted by containing the specific phthalocyanine as the charge generating material 8 in the photosensitive layer 4 or 14 as described above. Further, as described above, the electrophotographic photoreceptor according to the present invention may be either a laminated type as shown in FIG. 1 or a single-layer type photoreceptor as shown in FIG.
[0052]
As the conductive support 2, in any of the laminated type and single layer type photoreceptors, for example, metal materials such as aluminum, aluminum alloy, stainless steel, iron, gold, silver, copper, zinc, nickel and titanium, Plastic substrates with deposited aluminum, gold, silver, copper, nickel, indium oxide and tin oxide, polyester films and paper, plastics and paper containing conductive particles, and plastics containing conductive polymers can be used. . Examples of these shapes include a drum shape, a sheet shape, and a seamless belt shape.
[0053]
On the conductive support 2, a photosensitive layer 4 is formed in the case of a laminated type photoreceptor as shown in FIG. 1, and in the case of a single layer type photoreceptor as shown in FIG. 2, the photosensitive layer 14. Is formed.
[0054]
The photosensitive layer 4 of the multilayer electrophotographic photosensitive member is formed by sequentially laminating a charge generation layer 5 containing the specific crystalline phthalocyanine composition and a charge transport layer 6 on a conductive support 2. .
[0055]
As a method for forming the charge generation layer 5, there is a method in which a charge generation layer coating liquid obtained by pulverizing and dispersing the specific phthalocyanine compound is applied on the conductive support 2. Specifically, an organic solvent is added to the fine particles of the specific phthalocyanine compound, and the mixture is pulverized and dispersed by a ball mill, a sand grinder, a paint shaker, an ultrasonic disperser or the like to prepare a coating solution for a charge generation layer. The coating solution for the charge generation layer is formed by a baker applicator, a bar coater, casting, spin coating or the like when forming a sheet-shaped photoreceptor, and a spray method or a vertical ring method when forming a drum-shaped photoreceptor. Then, the charge generation layer 5 is formed by coating on the conductive support 2 by a dip coating method or the like.
[0056]
FIG. 3 is a configuration diagram showing an example of a dip coating apparatus used in the dip coating method. The cylindrical conductive substrate 2 is immersed in the coating solution 12 filled in the coating layer 13. The substrate 2 is lowered by the lifting device 10 including the motor 11 and immersed in the coating solution 12. The lifting device 10 can immerse the substrate 2 in the coating tank 13 by a desired depth by controlling the rotation amount of the motor 11. After the substrate 2 is sufficiently immersed, it is pulled up by the lifting device 10 at a constant speed or a speed that changes sequentially. The coating liquid 12 overflowed from the coating tank 13 during the substrate immersion is collected in the collection tank 14. The recovered coating solution is stirred by the stirring device 15 and then returned to the coating tank 13 by the pump 16.
[0057]
In the charge generation layer coating solution, for example, polyester resin, polyvinyl acetate, polyacrylic acid ester, polycarbonate, polyarylate, polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, phenoxy are used as binder resin 7 in order to increase binding properties. Resins, epoxy resins, urethane resins, melamine resins, silicone resins, acrylic resins, cellulose esters, cellulose ethers, vinyl chloride-vinyl acetate copolymer resins, and the like may be added. In addition, the charge generation layer 5 may contain various additives such as a leveling agent, an antioxidant, and a sensitizer for improving coating properties, as necessary.
[0058]
The thickness of the charge generation layer 5 is preferably 0.05 to 5 μm, and particularly preferably 0.1 to 1 μm.
[0059]
The charge transport layer 6 is mainly composed of a charge transport material 9 and a binder resin 18. Examples of the charge transport material 9 include electron-withdrawing materials such as 2,4,7-trinitrofluorenone, tetracyanoquinodimethane and diphenoquinone, carbazole, indole, imidazole, oxazole, pyrazole, oxadiazole, pyrazoline and thiadiazole. Electron donating properties such as heterocyclic compounds, aniline derivatives, hydrazone compounds, aromatic amine derivatives, styryl compounds, butadiene compounds, bisamine compounds, enamine compounds, and polymers having groups consisting of these compounds in the main chain or side chain Substances. In particular, a specific styryl compound, a butadiene compound represented by the following general formula (1), and a bisamine compound represented by the following general formula (2) are very high in mobility, and are suitable for high sensitivity and high resolution. It is. These charge transport materials 9 may be used alone or in combination.
[0060]
[Chemical 7]

[0061]
(Wherein R₁~ R_FourRepresents an aryl group which may have a substituent or an aralkyl group which may have a substituent. )
[0062]
[Chemical 8]

[0063]
(Wherein R_FiveAnd R₆Each represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, an alkoxycarbonyl group, or an amino group which may have a substituent. R₇Represents an alkyl group or an alkoxy group. )
Specific examples of the butadiene compound represented by the general formula (1) are shown in Tables 1 and 2.
[0064]
[Table 1]

[0065]
[Table 2]

[0066]
Specific examples of the bisamine compound represented by the general formula (2) are shown in Table 3.
[0067]
[Table 3]

[0068]
Examples of the binder resin 18 include vinyl polymers such as polycarbonate, polymethyl methacrylate, polystyrene, and polyvinyl chloride, copolymers thereof, polyester, polyester carbonate, polyarylate, polysulfone, polyimide, phenoxy resin, epoxy resin, and silicone. Resins etc. are mentioned, and these partially crosslinked cured products can also be used.
[0069]
The charge transport layer 6 is formed in the form in which the charge transport material 9 is bound to the binder resin 18. The ratio of the binder resin 18 and the charge transport material 9 is preferably 30 to 200 parts by weight, more preferably 40 to 150 parts by weight, with respect to 100 parts by weight of the binder resin. The charge transport layer 6 may contain additives such as known plasticizers, antioxidants, ultraviolet absorbers, and leveling agents in order to improve film formability, flexibility, and coating properties. The charge transport layer 6 is a device similar to the charge generation layer 5 in which the charge transport layer coating solution prepared in the same manner as the charge generation layer coating solution using the charge transport material 9 and the binder resin 18 is used. It is formed by coating on the charge generation layer 5 using
[0070]
The thickness of the charge transport layer 6 is preferably 5 to 50 μm, more preferably 10 to 45 μm.
[0071]
The photosensitive layer 14 of the single-layer type electrophotographic photosensitive member is configured by containing the specific phthalocyanine as the charge generation material 8 together with the charge transport material 9 on the conductive support 2. As a method for forming the photosensitive layer 14, a photosensitive layer in which the specific crystalline phthalocyanine composition is dispersed as the charge generating material 8 in a liquid having the same mixing ratio as the coating liquid for the charge transport layer of the single-layer type photoreceptor. There is a method of using a coating liquid for coating. In that case, the particle size of the specific crystalline phthalocyanine composition needs to be sufficiently small, and is preferably 1 μm or less. If the amount of the charge generating material 8 dispersed in the photosensitive layer 14 is too small, there is an adverse effect such as insufficient sensitivity, and excessive amount induces a decrease in chargeability and sensitivity, and is preferably 0.5 to 50% by weight. Is used at 1 to 20% by weight. Also for the photosensitive layer 14 of the single-layer type photoreceptor, in order to improve film forming property, flexibility, mechanical strength, etc., a conventionally known plasticizer, an additive for suppressing residual potential, and for improving dispersion stability. Dispersion aids, leveling agents such as silicone oil and fluorine oil for improving coating properties, surfactants, and other additives may be added.
[0072]
The film thickness of the photosensitive layer 14 is 5 to 40 μm, preferably 15 to 30 μm. An undercoat layer that is an intermediate layer may be provided between the conductive support 2 and the photosensitive layer 4 or 14. As the intermediate layer, for example, an aluminum anodic oxide coating, an inorganic layer such as aluminum oxide and aluminum hydroxide, or polyvinyl alcohol, casein, polyvinyl pyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide and polyamide, etc. An organic layer can be used. The undercoat layer is formed by applying an undercoat layer coating solution containing these materials onto the conductive support 2.
[0073]
Of these, polyamide resins are more preferred. The reason is that, as a characteristic of the binder resin, it does not dissolve or swell in the solvent used when forming the photoreceptor layer on the undercoat layer, and has excellent adhesion to the conductive support. This is because conditions such as having flexibility and being able to keep costs low are required. Of the polyamide resins, an alcohol-soluble nylon resin can be particularly preferably used. For example, such as so-called copolymer nylon obtained by copolymerizing 6-nylon, 66-nylon, 610-nylon, 11-nylon and 12-nylon, N-alkoxymethyl-modified nylon and N-alkoxyethyl-modified nylon. There is a type that chemically modified nylon.
[0074]
These intermediate layers may contain conductive or semiconductive fine particles such as metals or metal oxides such as aluminum, copper, tin, zinc and titanium.
[0075]
As the organic solvent used in the undercoat layer coating solution, a general organic solvent can be used. In particular, when a particularly preferable alcohol-soluble nylon resin is used as the binder resin for the undercoat layer, a lower alcohol group having 1 to 4 carbon atoms and an organic solvent other than the lower alcohol, such as dichloromethane, chloroform, 1,2- A single or mixed organic solvent selected from the group consisting of dichloroethane, 1,2-dichloropropane, toluene, tetrahydrofuran, 1,3-dioxolane and the like is preferable. By mixing an organic solvent other than the lower alcohol, the dispersibility of titanium oxide is improved as compared with the alcohol solvent alone, and the storage stability of the coating solution can be prolonged and the coating solution can be regenerated. In addition, when forming the undercoat layer by dip-coating the conductive support in the undercoat layer coating solution, coating defects and unevenness of the undercoat layer are prevented, and the photosensitive layer formed on the undercoat layer is uniform. Since it can be applied, it is possible to produce an electrophotographic photoreceptor having very good image characteristics without film defects.
[0076]
The film thickness of the intermediate layer is preferably from 0.01 to 20 μm, more preferably from 0.05 to 10 μm. If the thickness of the undercoat layer is less than 0.01 μm, the undercoat layer substantially does not function as an undercoat layer, and the surface of the conductive support 2 is not covered with a uniform surface property by covering the defects of the conductive support 2. Therefore, it becomes impossible to prevent the injection of charges from the surface, resulting in a decrease in chargeability. When the undercoat layer is applied by dip coating, it is difficult to make the thickness thicker than 20 μm, and the sensitivity of the photoconductor is reduced.
[0077]
The binder resin, metal oxide, and the like are dispersed in the organic solvent described above to prepare a coating solution for the undercoat layer. As a method for dispersing the coating solution for the undercoat layer, there are methods using a ball mill, a sand mill, an attritor, a vibration mill, an ultrasonic disperser, and the like. As a coating method of the undercoat layer coating solution, a general method such as the above-described dip coating method can be applied.
[0078]
In both the laminated type and single layer type photoreceptors, a protective layer may be provided on the photosensitive layer 4 or 14 to protect the surface of the photosensitive layer if necessary. A thermoplastic resin and light or thermosetting resin can be used for the surface protective layer. The protective layer may contain an ultraviolet absorber, an antioxidant, an inorganic material such as a metal oxide, an organic metal compound, and an electron accepting substance. In addition, as in the case of the photosensitive layer, the protective layer may be mixed with a plasticizer such as dibasic acid ester, fatty acid ester, phosphoric acid ester, phthalic acid ester and chlorinated paraffin to improve processability and plasticity. It may be applied to improve mechanical properties, or additives such as leveling agents may be mixed.
[0079]
FIG. 4 is a block diagram showing a laser printer 30 equipped with the electrophotographic photosensitive member according to the present invention. A laser printer 30 as an electrophotographic apparatus includes a photoconductor 100, a semiconductor laser 31, a corona charger 36, a developing device 37, a transfer charger 41, a separation charger 42, a fixing device 44, a paper discharge tray 45, and a cleaner 46. Consists of including. In the laser printer 30, the surface of the photoconductor 100 is uniformly charged to a negative polarity by the corona charger 36, and the semiconductor laser 31 performs light exposure based on image information to perform image exposure, and the photoconductor 100 is rotated to perform exposure. A reversal development method is adopted in which the region reaches a developing region facing the developing device, and negatively charged toner is attached to the exposed region for development.
[0080]
In an electrophotographic apparatus using such a semiconductor laser or a light emitting diode (LED) as an exposure light source, by mounting the electrophotographic photosensitive member containing the specific crystalline phthalocyanine composition, the periphery is irradiated with these exposure light sources. It is not exposed to weak light spreading in the area, dots do not spread, and a better latent image can be formed, so that high image quality can be obtained.
[0081]
When an image is formed using such a reversal development process, a toner image is formed in a portion where the surface charge of the exposed portion is reduced. Fogging of an image such as a black spot sticking occurs, resulting in significant image quality degradation. This causes a significant image defect such as black spots on a white background due to a decrease in chargeability in a minute region due to a defect in the conductive support or the photosensitive layer. However, in the electrophotographic photoreceptor in which the undercoat layer is formed as described above, it is possible to form a very uniform photosensitive layer coating film free from coating defects and unevenness. Therefore, when the electrophotographic photosensitive member is mounted, the surface charge does not decrease due to factors other than exposure, and there is no occurrence of black spots where toner adheres to a white background, and all of high sensitivity, high image quality and high resolution are achieved. A satisfactory electrophotographic apparatus such as a copying machine, a printer and a facsimile suitable for outputting digital data can be provided.
[0082]
【Example】
The electrophotographic photosensitive member and the electrophotographic apparatus using the same according to the present invention will be specifically described below with reference to examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded.
[0083]
(Production Example 1)
40 g of o-phthalodinitrile, 18 g of titanium tetrachloride, and 500 ml of α-chloronaphthalene were reacted by heating and stirring at 200 to 250 ° C. for 3 hours under a nitrogen atmosphere, allowed to cool to 100 to 130 ° C., and then filtered while hot And washed with 200 ml of α-chloronaphthalene heated to 100 ° C. to obtain a crude product of dichlorotitanium phthalocyanine. This crude product was washed with 200 ml of α-chloronaphthalene and then with 200 ml of methanol at room temperature, and further subjected to hot washing in 500 ml of methanol for 1 hour. After filtration, the obtained crude product was repeatedly washed with hot water in 500 ml of water until the pH reached 6-7, and then dried to obtain titanyl phthalocyanine crystals.
[0084]
Metal-free phthalocyanine was added to the obtained crystals, mixed with 1,3-dioxolane, milled with glass beads having a diameter of 2 mm by a paint conditioner device (manufactured by Red Level), washed with methanol, dried, A specific crystalline phthalocyanine composition in the present invention was obtained.
[0085]
About the obtained crystalline phthalocyanine composition, the X-ray-diffraction spectrum was measured on condition of the following. The crystalline phthalocyanine used in Example 5 described later was also measured under the same conditions.
X-ray source CuKα = 1.54Å
Voltage 30-40kV
Current 100mA
Start angle 5.0 °
Stop angle 30.0 °
Step angle 0.01-0.02 °
Measurement time 2.0-0.5 ° / min.
Measuring method θ / 2θ Scanning method
[0086]
The obtained crystalline phthalocyanine composition had an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54Å) of 7.0 °, 9.0 °, 14 at least at a Bragg angle (2θ ± 0.2 °). It was a crystalline phthalocyanine composition composed of titanyl phthalocyanine and metal-free phthalocyanine showing major peaks at .1 °, 18.0 °, 23.7 ° and 27.2 °.
[0087]
(Example 1)
0.9 part by weight of the crystalline phthalocyanine composition prepared in Production Example 1, 0.9 part by weight of χ-type metal-free phthalocyanine (Fastogen Blue 8120BS manufactured by Dainippon Ink and Co., Ltd.) and butyral resin (BL-1 manufactured by Sekisui Chemical Co., Ltd.) 1.2 parts by weight was mixed with 97 parts by weight of 1,3-dioxolane and dispersed with a paint shaker to prepare a charge generation layer coating solution. The χ-type metal-free phthalocyanine is 7.6 °, 9.0 °, 16 ° at least at a Bragg angle (2θ ± 0.2 °) in an X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54Å). Major peaks are shown at .8 °, 17.3 ° and 22.3 °. When the crystalline phthalocyanine composition of the prepared coating solution for charge generation layer was measured by X-ray diffraction spectrum, at least the Bragg angle (2θ ± 0.2 °) in the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54１．５) was measured. ) Showed X-ray diffraction spectra having peaks at 7.0 °, 7.6 °, 9.0 °, 13.6 °, 16.8 ° and 27.2 °. The charge generation layer coating solution is filled in a coating tank 13 of a dip coating apparatus as shown in FIG. 3, and an aluminum drum-shaped support having a diameter of 30 mm and a total length of 326.3 mm is immersed and pulled up as a conductive support. Then, it was naturally dried to form a charge generation layer having a thickness of 0.5 μm.
[0088]
10 parts by weight of a styryl compound represented by the following structural formula (5) and 16 parts by weight of a polycarbonate resin (PCZ400 manufactured by Mitsubishi Gas Chemical Company) having a repeating unit represented by the following structural formula (6) are mixed, and THF is used as a solvent. A coating solution for a charge transport layer having a solid content of 21% by weight was prepared. The prepared charge transport layer coating solution was applied onto the charge generation layer in the same manner as the charge generation layer coating solution and dried at 110 ° C. for 1 hour to form a charge transport layer having a thickness of 22 μm.
A multilayer electrophotographic photosensitive member was produced as described above.
[0089]
[Chemical 9]

[0090]
[Chemical Formula 10]

[0091]
(Example 2)
1.8 parts by weight of the crystalline phthalocyanine composition prepared in Production Example 1 and 1.2 parts by weight of butyral resin (BL-1 manufactured by Sekisui Chemical Co., Ltd.) were mixed in 97 parts by weight of 1,3-dioxolane. Dispersion treatment was performed with a paint shaker to obtain a coating solution A for charge generation layer.
[0092]
Further, in the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54Å), at least Bragg angle (2θ ± 0.2 °) is 7.6 °, 9.0 °, 16.8 °, 17.3 °. And 1.8 parts by weight of χ-type metal-free phthalocyanine having a main peak at 22.3 ° (Fastogen Blue 8120BS manufactured by Dainippon Ink and Co., Ltd.) and 1.2 parts by weight of butyral resin (BL-1 manufactured by Sekisui Chemical Co., Ltd.) Was mixed with 97 parts by weight of 1,3-dioxolane and dispersed with a paint shaker to obtain a coating solution B for charge generation layer.
[0093]
A coating solution obtained by mixing these two charge generation layer coating solutions A and B in a weight ratio of A: B = 60: 40 is formed on an aluminum drum-shaped conductive support having a diameter of 30 mm and a total length of 326.3 mm. After being dip-coated, the film was naturally dried to form a charge generation layer having a thickness of 0.5 μm.
[0094]
FIG. 5 is a diagram showing an X-ray diffraction spectrum of the crystalline phthalocyanine composition obtained in Example 2 of the present invention. When the X-ray diffraction spectrum of the crystalline phthalocyanine composition of the coating solution (A: B = 60: 40) obtained by mixing the coating solutions A and B for charge generation layer was measured, the CuKα characteristic X-ray (wavelength: 1.54Å) was measured. X-ray diffraction spectrum has peaks at least at Bragg angles (2θ ± 0.2 °) at 7.0 °, 7.6 °, 9.0 °, 13.6 °, 16.8 ° and 27.2 °. An X-ray diffraction spectrum was shown.
[0095]
Next, 10 parts by weight of a bisamine compound represented by the following structural formula (7) and 16 parts by weight of a polycarbonate resin (Mitsubishi Gas Chemical Co., Ltd .: PCZ400) having a repeating unit represented by the structural formula (6) are mixed. A coating solution for a charge transport layer having a solid content of 21% by weight was prepared using THF as a solvent. The charge transport layer coating solution was applied onto the previously formed charge generation layer and dried at 110 ° C. for 1 hour to form a charge transport layer having a thickness of 22 μm.
A multilayer photoreceptor was produced as described above.
[0096]
Embedded image

[0097]
(Example 3)
A photoconductor was prepared in the same manner as in Example 2 except that the charge generation layer coating solutions A and B prepared in Example 2 were used as a coating solution in which the weight ratio was A: B = 90: 10. did.
[0098]
(Example 4)
A photoconductor was produced in the same manner as in Example 2 except that the charge generation layer coating solutions A and B prepared in Example 2 were used as a coating solution in which the weight ratio was A: B = 30: 70. did.
[0099]
(Example 5)
A crystalline phthalocyanine composition obtained by mixing the coating solutions A and B for charge generation layer used in Example 2 in a weight ratio of A: B = 60: 40 and then co-dispersing with a paint shaker A coating solution for a charge generation layer was prepared. The prepared coating solution for charge generation layer was dip coated on the conductive support in the same manner as in Example 2, and a charge generation layer having a thickness of 0.5 μm was formed by natural drying. Further, a charge transport layer was formed in the same manner as in Example 2 to produce a photoreceptor.
[0100]
FIG. 6 is an X-ray diffraction spectrum of the crystalline phthalocyanine composition obtained in Example 5 of the present invention. When the crystalline phthalocyanine composition of the coating liquid obtained by co-dispersing the coating liquid (A: B = 60: 40) obtained by mixing the coating liquids A and B for charge generation layer was measured by X-ray diffraction spectrum, CuKα characteristics were obtained. In an X-ray diffraction spectrum for X-rays (wavelength: 1.54 mm), at least Bragg angles (2θ ± 0.2 °) are 7.0 °, 7.6 °, 9.0 °, 13.6 °, 16.8. An X-ray diffraction spectrum having main peaks at ° and 27.2 °, with a peak height of 16.8 ° relative to 7.0 ° being less than twice.
[0101]
(Comparative Example 1)
A photoconductor was prepared in the same manner as in Example 2 except that the charge generation layer was formed using the coating solution A for charge generation layer prepared in Example 2.
[0102]
(Comparative Example 2)
A photoconductor was prepared in the same manner as in Example 2 except that the charge generation layer was formed using the charge generation layer coating solution B prepared in Example 2.
[0103]
(Evaluation 1)
The electrophotographic photosensitive member produced in Examples 1 to 5 and Comparative Examples 1 and 2 was modified so that a dot equivalent to 1200 dpi could be output from a copier (AR-N200 manufactured by Sharp Corporation) employing a commercially available reversal development process. It was mounted on an experimental machine and the resolution was examined. Create data with one white dot written on a PC (data that scans the entire surface of the laser and turns off only one dot), and sends this data to the experimental machine via the printer interface. The output image printed out under normal temperature and normal humidity of 60% RH (hereinafter referred to as “N / N environment”) was observed. The resolution (N / N resolution) was evaluated for the image output in the N / N environment. In addition, a solid image was output from the experimental machine in a low temperature and low humidity environment of 5 ° C./20% RH (hereinafter referred to as “L / L environment”). The sensitivity (L / L sensitivity) was evaluated for the solid black image output under the L / L environment. Further, a white image was output under a high temperature and high humidity environment of 35 ° C./85% RH (hereinafter referred to as “H / H environment”). The image quality (H / H image) was evaluated for the white solid image output in the H / H environment.
The above evaluation results are shown in Table 4.
[0104]
[Table 4]

[0105]
As can be seen from Table 4, for each of the Examples, the N / N resolution was clearly confirmed as a white dot of 1 dot on the solid black. From this, it was found that the photoconductor according to the present invention can output a sufficiently high resolution image. Also, in any of the examples, a good image without a decrease in image density was obtained with L / L sensitivity. In the H / H image, some black spots occurred in Examples 1 to 3, but it was found that all of them were not a big problem in actual use, and a sufficiently high resolution image could be output. In Comparative Example 1, although the data for outputting the dots was transmitted, the output image was solid and it was found that the dots were not formed accurately. In Comparative Example 2, dots in the output image were found and the solid density was lowered.
[0106]
From the above results, by forming a charge generation layer containing a charge generation material having a specific crystal type in the photosensitive layer provided on the conductive support, it is possible to maintain the resolution in an H / H environment. Can suppress black spots and prevent a decrease in sensitivity in an L / L environment. That is, an electrophotographic photosensitive member satisfying all of high sensitivity, high image quality, and high resolution can be produced.
[0107]
(Example 6)
An electrophotographic photosensitive member was produced in the same manner as in Example 2, except that a butadiene compound represented by the following structural formula (8) was used instead of the bisamine compound used in Example 2.
[0108]
Embedded image

[0109]
(Example 7)
An electrophotographic photoreceptor was produced in the same manner as in Example 5 except that the butadiene compound represented by the structural formula (8) was used instead of the bisamine compound used in Example 5.
[0110]
(Comparative Example 3)
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 1 except that the butadiene compound represented by the structural formula (8) was used instead of the bisamine compound used in Comparative Example 1.
[0111]
  (Comparative Example 4)
  Comparative Example except that the butadiene compound represented by the structural formula (8) was used instead of the bisamine compound used in Comparative Example 2.2In the same manner as above, an electrophotographic photosensitive member was produced.
[0112]
(Evaluation 2)
The light attenuation characteristics of the electrophotographic photosensitive members produced in Examples 6 and 7 and Comparative Examples 3 and 4 were measured.
Using a drum sensitivity tester (manufactured by Gentec), the surface of the electrophotographic photosensitive member is charged to −600 ± 20 V with a scorotron charger, and the light intensity of the semiconductor laser light (wavelength 780 nm) as the exposure light source is ND. The surface potential of each light intensity was measured by adjusting with a filter and irradiating the surface of the photoreceptor.
[0113]
FIG. 7 and FIG. 8 are diagrams showing light attenuation characteristics in the electrophotographic photosensitive members of Examples and Comparative Examples of the present invention.
[0114]
The light attenuation characteristics of the photoconductor of Example 6 were found to be small for weak exposure and sufficiently attenuated for strong exposure as shown in photoconductor A of FIG. . Regarding the light attenuation characteristics of the photoconductor of Example 7, as shown in Photoconductor B of FIG. 7, the light attenuation is small for weak exposure and is completely attenuated for strong exposure. It was found that the sensitivity was further improved. The light attenuation characteristic of the photoconductor of Comparative Example 3 was found to be large even with weak exposure as shown in photoconductor C of FIG. Further, for the photoconductor of Comparative Example 3, when an image in which data in which one white dot was written on black was output in the same manner as in Evaluation 1, an image was output despite sending data for outputting dots. The resulting image was solid black, and it was found that dots were not formed accurately. It has been found that the photoattenuator of Comparative Example 4 has insufficient light attenuation even with strong exposure and has a large residual potential as shown in Photoreceptor D of FIG. Further, regarding the photoconductor of Comparative Example 4, when an image in which data in which one white dot is written on black was output in the same manner as in Evaluation 1, the dot of the output image can be discriminated, but the black solid portion. The concentration was low.
[0115]
(Example 8)
10 parts by weight of the crystalline phthalocyanine composition prepared in Production Example 1 and 5 parts by weight of χ-type metal-free phthalocyanine (Fastgen Blue 8120BS manufactured by Dainippon Ink and Co., Ltd.) are mixed with 185 parts by weight of 1,3-dioxolane, and a paint shaker is used. After the dispersion treatment, 100 parts by weight of a butadiene compound represented by the structural formula (8) and 160 parts by weight of a polycarbonate resin (PCZ400 manufactured by Mitsubishi Gas Chemical Co., Ltd.) are mixed, and an application having a solid content of 21% by weight using THF as a solvent. A liquid was prepared. The coating solution is filled in the coating tank, and an aluminum drum-shaped support having a diameter of 30 mm and a total length of 326.3 mm is dipped and pulled up as a conductive support, dried at 110 ° C. for 1 hour, and photosensitive layer 14 having a thickness of 20 μm. To form a single layer type photoreceptor.
[0116]
Example 9
An electrophotographic photosensitive member was produced in the same manner as in Example 5 except that a hydrazone compound represented by the following structural formula (9) was used instead of the bisamine compound used in Example 5.
[0117]
Embedded image

[0118]
(Comparative Example 5)
An electrophotographic photoreceptor was produced in the same manner as in Comparative Example 1 except that the hydrazone compound represented by the structural formula (9) was used instead of the bisamine compound used in Comparative Example 1.
[0119]
(Comparative Example 6)
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 2, except that the hydrazone compound represented by the structural formula (9) was used instead of the bisamine compound used in Comparative Example 2.
[0120]
(Evaluation 3)
The electrophotographic photosensitive member produced in Example 8 was modified so that a dot (equivalent to 1200 dpi) could be output from a copying machine (Sharp Corporation AR-N200) employing a commercially available reversal development process, and further modified to a positive charging process. It was mounted on an experimental machine and the resolution was examined. Data is created by writing a white dot on a solid black on a personal computer (data that scans the entire surface of the laser and turns off only one dot), and this data is sent to the experimental machine via the printer interface and printed out. The output image was observed. The light attenuation characteristics of the photoconductors of Example 9 and Comparative Examples 5 and 6 were measured in the same manner as in Evaluation 2.
[0121]
For the photoconductor of Example 8, a single dot of white point was clearly confirmed on the black solid. It was found that the photoconductor of Example 8 can output a sufficiently high resolution image. The light attenuation characteristic of the photoconductor of Example 9 is small for light exposure as shown in the photoconductor E of FIG. It was found that the sensitivity improvement from Comparative Example 5 was small. The light attenuation characteristics of the photoconductor of Comparative Example 5 were found to be large even with weak exposure as shown in photoconductor F of FIG. When the image of the photoconductor of Comparative Example 5 was examined, it was found that although the data for outputting the dots was sent, the output image was black solid and the dots were not formed properly. The light attenuation characteristics of the photoconductor of Comparative Example 6 were found to be insufficient even after strong exposure as shown by the photoconductor G of FIG. When the image of the photoconductor of Comparative Example 6 was examined, the dots of the output image could be discriminated, but the density of the black solid portion was low.
[0122]
From the above results, by providing a photosensitive layer containing a specific crystalline phthalocyanine composition, it is not a photosensitive member (comparative photosensitive members C and F) that is highly sensitive to small exposure energy, but weak exposure. It is possible to provide a highly sensitive photoreceptor (photosensitive bodies A and B) that has little light attenuation, is highly sensitive to strong exposure, and is completely attenuated in potential and linearly responds to exposure energy.
[0123]
In addition, since the photosensitive member A is more sensitive to stronger exposure energy than the photosensitive member E, the intended effect in the present invention is exhibited by the charge transport material having a specific high mobility. I understand that. That is, an electrophotographic photosensitive member that satisfies all of high sensitivity, high image quality, and high resolution can be produced by the charge transport material.
[0124]
【The invention's effect】
  According to the invention, in the photosensitive layerIn the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54 Å), at Bragg angle (2θ ± 0.2 °), at least 7.0 °, 9.0 °, 14.1 °, 18.0 In an X-ray diffraction spectrum for a composition composed of titanyl phthalocyanine and metal-free phthalocyanine having major peaks at °, 23.7 ° and 27.2 °, and CuKα characteristic X-ray (wavelength: 1.54Å), Χ-type metal-free phthalocyanine with major peaks at an angle (2θ ± 0.2 °) of at least 7.6 °, 9.0 °, 16.8 °, 17.3 ° and 22.3 ° ,By using the crystalline phthalocyanine composition having the specific X-ray diffraction spectrum as a charge generating material, light attenuation is small for weak exposure, high sensitivity to strong exposure, complete potential attenuation, and exposure energy. On the other hand, as a result of obtaining a highly sensitive photoconductor that responds linearly, an electrophotographic photoconductor satisfying all of high sensitivity, high image quality and high resolution can be provided.
[0125]
Further, according to the present invention, in an electrophotographic apparatus using a semiconductor laser or a light emitting diode (LED) as an exposure light source and using a reversal development process, the electrophotographic photosensitive member is mounted so that high sensitivity, high image quality, and high resolution are achieved. An electrophotographic apparatus satisfying all of the above can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration example of a multilayer electrophotographic photosensitive member.
FIG. 2 is a cross-sectional view illustrating a configuration example of a single-layer type electrophotographic photosensitive member.
FIG. 3 is a configuration diagram showing an example of a dip coating apparatus used in a dip coating method.
FIG. 4 is a configuration diagram showing a laser printer 30 equipped with an electrophotographic photosensitive member according to the present invention.
FIG. 5 is an X-ray diffraction spectrum of the crystalline phthalocyanine composition obtained in Example 2 of the present invention.
6 is a graph showing an X-ray diffraction spectrum of the crystalline phthalocyanine composition obtained in Example 5 of the present invention. FIG.
FIG. 7 is a diagram showing light attenuation characteristics in electrophotographic photosensitive members of examples and comparative examples of the present invention.
FIG. 8 is a diagram showing light attenuation characteristics in electrophotographic photosensitive members of examples and comparative examples of the present invention.
[Explanation of symbols]
2 Conductive support
4,14 Photosensitive layer
5 Charge generation layer
6 Charge transport layer
7 Binder resin
8 Charge generation materials
9 Charge transport materials
19 Binder resin

Claims (8)

An electrophotographic photosensitive member having a conductive support and a photosensitive layer formed on the conductive support,
The photosensitive layer has an Bragg angle (2θ ± 0.2 °) of at least 7.0 °, 7.6 °, 9.0 ° in an X-ray diffraction spectrum with respect to CuKα characteristic X-ray (wavelength: 1.54Å), Containing a crystalline phthalocyanine composition having peaks at 13.6 °, 16.8 ° and 27.2 ° ;
The crystalline phthalocyanine composition is
In the X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54Å), at least 7.0 °, 9.0 °, 14.1 °, 18.0 ° at Bragg angle (2θ ± 0.2 °) A composition comprising titanyl phthalocyanine and metal-free phthalocyanine having major peaks at 23.7 ° and 27.2 °;
In an X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54１．５), at least 7.6 °, 9.0 °, 16.8 °, 17.3 ° at a Bragg angle (2θ ± 0.2 °) And an χ-type metal-free phthalocyanine having a main peak at 22.3 ° .   The crystalline phthalocyanine composition has a Bragg angle (2θ ± 0.2 °) and a peak of 16.8 ° with respect to 7.0 ° in an X-ray diffraction spectrum for CuKα characteristic X-ray (wavelength: 1.54１．５). 2. The electrophotographic photosensitive member according to claim 1, wherein the height ratio is less than twice. 3. The electrophotographic photosensitive member according to claim 1, wherein the x-type metal-free phthalocyanine is contained in the crystalline phthalocyanine composition in an amount of 10 to 70% by weight . The electrophotographic photosensitive member according to claim 1 , wherein the photosensitive layer contains a butadiene compound represented by the following general formula (1) as a charge transport material .

(Wherein, R ₁ to R ₄ represents an aralkyl group which may have an aryl group or a substituted group may have a substituent.) The photosensitive layer is a charge transport material, an electrophotographic photosensitive member as claimed in any one of claims 1 to 3, characterized in that it contains a bisamine compound represented by the following general formula (2).

(Wherein R ₅ and R ₆ each represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, an alkoxycarbonyl group, or an amino group which may have a substituent. R ₇ represents an alkyl group or an alkoxy group. Represents a group.) The photosensitive layer is at least claim 1 in which a charge generation layer containing the crystalline phthalocyanine composition as the charge onset antibiotic, a charge transport layer containing a charge transport material is characterized in that formed by laminating The electrophotographic photosensitive member according to any one of 5 . Mounting the electrophotographic photosensitive member according to any one of claims 1 to 6, the child photographic apparatus electrostatic you comprising the semiconductor laser or light emitting diode to image exposure with respect to the electrophotographic photosensitive member. Charged with an image exposed electrophotographic photosensitive member, reversal development to electrophotographic apparatus according to claim 7 Symbol mounting characterized by comprising means for obtaining an image.

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