JP3936537B2 - Electrophotographic photoreceptor and method for producing the same - Google Patents

Description

【００４０】
【化２】

【００４１】
Ｒ₄、Ｒ₅、Ｒ₆、Ｒ₇は、それぞれ独立して水素原子、置換もしくは無置換のアルキル基又はハロゲン原子を表わし、又は置換もしくは無置換のアリール基を表わす。Ｘは脂肪族の２価基、環状脂肪族の２価基を表わし、Ｙは単結合、炭素原子数１〜１２の直鎖状、分岐状もしくは環状のアルキレン基、−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ₂−、−ＣＯ−、−ＣＯ−Ｏ−Ｚ−Ｏ−ＣＯ−（式中Ｚは脂肪族の２価基を表わす。）または、
【００４２】
【化３】

（式中、ａは１〜２０の整数、ｂは１〜２０００の整数、Ｒ₈、Ｒ₉は置換または無置換のアルキル基又はアリール基を表わす。）を表わす。ここで、Ｒ₆とＲ₇、Ｒ₈とＲ₉は、それぞれ同一でも異なってもよい。ｐ、ｑは組成を表わし、０．１≦ｐ≦１、０≦ｑ≦０．９、ｎは繰り返し単位数を表わし、５〜５０００の整数である。
【００４３】
これらポリカーボネートは強靱性が高く、フィルム性が良いことが挙げられ、またこのフィラー層は電荷輸送機能をもたせるため電荷輸送物質との相溶性が良いことが重要な条件であることから前記一般式（１）、及び一般式（２）で示されるポリカーボネートが好適である。
【００４４】
フィラーを含む表面層には電荷輸送機能を付与するために電荷輸送物質を添加する。添加する電荷輸送物質としてはオキサゾール誘導体、オキサジアゾール誘導体、イミダゾール誘導体、トリフェニルアミン誘導体、９−（ｐ−ジエチルアミノスチリルアントラセン）、１，１−ビス−（４−ジベンジルアミノフェニル）プロパン、スチリルアントラセン、スチリルピラゾリン、フェニルヒドラゾン類、α−フェニルスチルベン誘導体、チアゾール誘導体、トリアゾール誘導体、フェナジン誘導体、アクリジン誘導体、ベンゾフラン誘導体、ベンズイミダゾ−ル誘導体、チオフェン誘導体などが挙げられる。これらの電荷輸送物質は、単独または２種以上の混合物として用いることができる。
【００４５】
特に、下記一般式（３）で示される電荷輸送物質は移動度が速く、上記バインダー樹脂との相溶性が良く、好ましい。
【００４６】
【化４】

Ｒ₁は水素原子、置換もしくは無置換のアルキル基又はハロゲン原子を表わし、又は置換もしくは無置換のアリール基を表わす。Ｒ₂、Ｒ₃は置換もしくは無置換のアリール基を表わす。Ｒ₁は水素原子、それぞれ独立して置換もしくは無置換のアルキル基又はハロゲン原子を表わすが、その具体例としては以下のものを挙げることができ、同一であっても異なってもよい。
【００４７】
アルキル基として好ましくは、Ｃ₁〜Ｃ₁₂とりわけＣ₁〜Ｃ₈、さらに好ましくはＣ₁〜Ｃ₄の直鎖または分岐鎖のアルキル基であり、これらのアルキル基はさらにフッ素原子、水酸基、シアノ基、Ｃ₁〜Ｃ₄のアルコキシ基、フェニル基、又はハロゲン原子、Ｃ₁〜Ｃ₄のアルキル基もしくはＣ₁〜Ｃ₄のアルコキシ基で置換されたフェニル基を含有しても良い。
【００４８】
具体的には、メチル基、エチル基、ｎ−プロピル基、ｉ−プロピル基、ｔ−ブチル基、ｓ−ブチル基、ｎ−ブチル基、ｉ−ブチル基、トリフルオロメチル基、２−ヒドロキシエチル基、２−シアノエチル基、２−エトキシエチル基、２−メトキシエチル基、ベンジル基、４−クロロベンジル基、４−メチルベンジル基、４−メトキシベンジル基、４−フェニルベンジル基等が挙げられる。
【００４９】
ハロゲン原子としては、フッ素原子、塩素原子、臭素原子、ヨウ素原子が挙げられる。Ｒ₂、Ｒ₃は置換もしくは無置換のアリール基を表わすが、その具体例としては以下のものを挙げることができ、同一であっても異なってもよい。
【００５０】
芳香族炭化水素基としては、スチリル基、フェニル基、縮合多環基としてナフチル基、ピレニル基、２−フルオレニル基、９，９−ジメチル−２−フルオレニル基、アズレニル基、アントリル基、トリフェニレニル基、クリセニル基、フルオレニリデンフェニル基、５Ｈ−ジベンゾ［ａ，ｄ］シクロヘプテニリデンフェニル基、非縮合多環基としてビフェニリル基、ターフェニリル基などが挙げられる。
【００５１】
複素環基としては、チエニル基、ベンゾチエニル基、フリル基、ベンゾフラニル基、カルバゾリル基などが挙げられる。
【００５２】
上述のアリール基は、以下に示す基を置環基として有してもよい。
（１）ハロゲン原子、トリフルオロメチル基、シアノ基、ニトロ基。
（２）アルキル基としては、上記のＲ₁、Ｒ₂、Ｒ₃と同様のものが挙げられる。
（３）アルコキシ基としては、アルキル基は（２）で定義したアルキル基を表わす。具体的には、メトキシ基、エトキシ基、ｎ−プロポキシ基、ｉ−プロポキシ基、ｔ−ブトキシ基、ｎ−ブトキシ基、ｓ−ブトキシ基、ｉ−ブトキシ基、２−ヒドロキシエトキシ基、２−シアノエトキシ基、ベンジルオキシ基、４−メチルベンジルオキシ基、トリフルオロメトキシ基等が挙げられる。
（４）アリールオキシ基としては、アリール基としてフェニル基、ナフチル基が挙げられる。これは、Ｃ₁〜Ｃ₄のアルコキシ基、Ｃ₁〜Ｃ₄のアルキル基またはハロゲン原子を置換基として含有しても良い。具体的には、フェノキシ基、１−ナフチルオキシ基、２−ナフチルオキシ基、４−メチルフェノキシ基、４−メトキシフェノキシ基、４−クロロフェノキシ基、６−メチル−２−ナフチルオキシ基等が挙げられる。
（５）置換メルカプト基またはアリールメルカプト基としては、具体的にはメチルチオ基、エチルチオ基、フェニルチオ基、ｐ−メチルフェニルチオ基等が挙げられる。
（６）アルキル置換アミノ基としては、アルキル基は（２）で定義したアルキル基を表わす。具体的には、ジメチルアミノ基、ジエチルアミノ基、Ｎ−メチル−Ｎ−プロピルアミノ基、Ｎ，Ｎ−ジベンジルアミノ基等が挙げられる。
（７）アシル基としては、具体的にはアセチル基、プロピオニル基、ブチリル基、マロニル基、ベンゾイル基等が挙げられる。
【００５３】
フィラー含む表面層中の電荷輸送物質（Ｄ）、バインダー樹脂（Ｒ）及びフィラー（Ｆ）の含有量比率はＤ：Ｒ：Ｆ＝１０〜４０：３５〜５５：５〜４０である。電荷輸送物質が１０重量％以下になると電荷輸送性の低下に起因すると考えられる明部電位上昇が起き、４０重量％以上であると膜強度低下が発生する。バインダー樹脂は電荷輸送物質、及びフィラーを固定させるために用いられ、３５重量％以下であるとフィラー層の脆化が発生し、５５重量％以上であると電荷輸送物質、及びフィラー量とのバランスの点で電気特性、膜強度で好ましくない。フィラー量は５重量％以下であると耐摩耗性の点で好ましくなく、４０重量％以上であると膜の不透明化による地汚れなど画像劣化が発生する。
【００５４】
分散溶媒としてはメチルエチルケトン、アセトン、メチルイソブチルケトン、シクロヘキサノン、シクロペンタノン等のケトン類、ジオキサン、１，３−ジオキソラン、テトラヒドロフラン、エチルセロソルブなどのエーテル類、トルエン、キシレンなどの芳香族類、クロロベンゼン、ジクロルメタンなどのハロゲン類、酢酸エチル、酢酸ブチルなどのエステル類が使用され、ボールミル、サンドミル、振動ミルなどを用いて分散、粉砕する。
【００５５】
フィラーの分散状態は体積平均粒径が０．０５〜１．５μｍ、好ましくは０．２〜１．０μｍに粉砕、分散するのが好ましい。体積平均粒径が０．２μｍよりも小さいと、耐摩耗性が低下するという欠点があり、体積平均粒径が１．０μｍよりも大きいと書き込み光の散乱による解像度低下が発生したり、表面に突出してクリーニングブレードを傷つけクリーニング不良が発生してしまう。
【００５６】
フィラーを含む最表面層の膜厚は０．５〜１０μｍで、好ましくは１〜６μｍである。塗工方法としては浸漬法、スプレー塗工法、リングコート法、ロールコータ法、グラビア塗工法、ノズルコート法、スクリーン印刷法等が採用される。電荷輸送物質とバインダー樹脂から構成される電荷輸送層上にフィラーを含む表面層を設ける場合、電荷輸送層に用いられたバインダー樹脂とフィラー層に用いられるバインダー樹脂の構造は同じでも異なっていても構わない。
【００５７】
以下に、本発明の電子写真感光体を図面に沿って説明する。
図１は、本発明に使用する電子写真感光体の構成例を表わす断面図であり、導電性支持体（１）上に電荷発生物質と電荷輸送物質を主成分とする単層感光層（２）が設けられ、その上にフィラーを含む表面層（３）が設けられている。
図２は、本発明の電子写真感光体の他の構成例を表わす断面図であり、導電性支持体（１）上に電荷発生物質を主成分とする電荷発生層（４）と電荷輸送物質を主成分とする電荷輸送層（５）とが積層され、そらにその上にフィラーを含む表面層（３）が設けられている。
【００５８】
上記フィラーを含む表面層は下記の層上に設けられる。
導電性支持体としては、体積抵抗１０¹⁰Ω以下の導電性を示すもの、例えばアルミニウム、ニッケル、クロム、ニクロム、銅、銀、金、白金、鉄などの金属、酸化スズ、酸化インジウムなどの酸化物を、蒸着またはスパッタリングによりフィルム状もしくは円筒状のプラスチック、紙等に被覆したもの、あるいはアルミニウム、アルミニウム合金、ニッケル、ステンレスなどの板およびそれらをＤ．Ｉ．，Ｉ．Ｉ．，押出し、引き抜きなどの工法で素管化後、切削、超仕上げ、研磨などで表面処理した管などを使用することができる。
【００５９】
本発明における感光層は、単層型でも積層型でもよいが、ここでは説明の都合上、まず積層型について述べる。
はじめに、電荷発生層について説明する。電荷発生層は、電荷発生物質を主成分とする層で、必要に応じてバインダ−樹脂を用いることもある。電荷発生物質としては、無機系材料と有機系材料を用いることができる。
【００６０】
無機系材料には、結晶セレン、アモルファス・セレン、セレン−テルル、セレン−テルル−ハロゲン、セレン−ヒ素化合物や、アモルファス・シリコン等が挙げられる。アモルファス・シリコンにおいては、ダングリングボンドを水素原子、ハロゲン原子でターミネートしたものや、ホウ素原子、リン原子等をドープしたものが良好に用いられる。
【００６１】
一方、有機系材料としては、公知の材料を用いることができる。例えば、金属フタロシアニン、無金属フタロシアニンなどのフタロシアニン系顔料、アズレニウム塩顔料、スクエアリック酸メチン顔料、カルバゾール骨格を有するアゾ顔料、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、ジベンゾチオフェン骨格を有するアゾ顔料、フルオレノ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、ジスチリルオキサジアゾール骨格を有するアゾ顔料、ジスチリルカルバゾール骨格を有するアゾ顔料、ペリレン系顔料、アントラキノン系または多環キノン系顔料、キノンイミン系顔料、ジフェニルメタン及びトリフェニルメタン系顔料、ベンゾキノン及びナフトキノン系顔料、シアニン及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などが挙げられる。これらの電荷発生物質は、単独または２種以上の混合物として用いることができる。
【００６２】
電荷発生層に必要に応じて用いられるバインダー樹脂としては、ポリアミド、ポリウレタン、エポキシ樹脂、ポリケトン、ポリカーボネ−ト、シリコーン樹脂、アクリル樹脂、ポリビニルブチラール、ポリビニルホルマール、ポリビニルケトン、ポリスチレン、ポリ−Ｎ−ビニルカルバゾール、ポリアクリルアミドなどが用いられる。これらのバインダー樹脂は、単独または２種以上の混合物として用いることができる。更に、必要に応じて電荷輸送物質を添加してもよい。
【００６３】
電荷輸送物質としては、以下に表わされる電子供与性物質が挙げられ、良好に用いられる。たとえば、オキサゾール誘導体、オキサジアゾール誘導体、イミダゾール誘導体、トリフェニルアミン誘導体、９−（ｐ−ジエチルアミノスチリルアントラセン）、１，１−ビス−（４−ジベンジルアミノフェニル）プロパン、スチリルアントラセン、スチリルピラゾリン、フェニルヒドラゾン類、α−フェニルスチルベン誘導体、チアゾール誘導体、トリアゾール誘導体、フェナジン誘導体、アクリジン誘導体、ベンゾフラン誘導体、ベンズイミダゾール誘導体、チオフェン誘導体などが挙げられる。これらの電荷輸送物質は、単独または２種以上の混合物として用いることができる。
【００６４】
電荷発生層を形成する方法には、真空薄膜作製法と溶液分散系からのキャスティング法とが大きく挙げられる。
前者の方法には、真空蒸着法、グロー放電分解法、イオンプレーティング法、スパッタリング法、反応性スパッタリング法、ＣＶＤ法等が用いられ、上述した無機系材料、有機系材料が良好に形成できる。
【００６５】
また、後述のキャスティング法によって電荷発生層を設けるには、上述した無機系もしくは有機系電荷発生物質を必要ならばバインダー樹脂と共にテトラヒドロフラン、シクロヘキサノン、ジオキサン、ジクロロエタン、ブタノン等の溶媒を用いてボールミル、アトライター、サンドミル等により分散し、分散液を適度に希釈して塗布することにより、形成できる。塗布は、浸漬塗工法やスプレーコート、ビードコート法などを用いて行なうことができる。
以上のようにして設けられる電荷発生層の膜厚は、０．０１〜５μｍ程度が適当であり、好ましくは０．０５〜２μｍである。
【００６６】
次に、電荷輸送層について説明する。
電荷輸送層は、電荷輸送物質とバインダー樹脂とを共に溶解、塗工し電荷輸送層として使用できる。バインダー樹脂としてはフィルム性の良いポリカーボネート（ビスフェノールＡタイプ、ビスフェノールＺタイプ、ビスフェノールＣタイプ、あるいはこれら共重合体）、ポリアリレート、ポリスルフォン、ポリエステル、メタクリル樹脂、ポリスチレン、酢酸ビニル、エポキシ樹脂、フェノキシ樹脂などが用いられる。これらのバインダーは、単独または２種以上の混合物として用いることができる。
【００６７】
電荷輸送層に使用される電荷輸送物質は、オキサゾール誘導体、オキサジアゾール誘導体（特開昭５２−１３９０６５号公報、５２−１３９０６６号公報に記載）、イミダゾール誘導体、トリフェニルアミン誘導体（特願平１−７７８３９号明細書に記載）、ベンジジン誘導体（特公昭５８−３２３７２号公報に記載）、α−フェニルスチルベン誘導体（特開昭５７−７３０７５号公報に記載）、ヒドラゾン誘導体（特開昭５５−１５４９５５号公報、５５−１５６９５４号公報、５５−５２０６３号公報、５６−８１８５０号公報等に記載）、トリフェニルメタン誘導体（特公昭５１−１０９８３号公報に記載）、アントラセン誘導体（特開昭５１−９４８２９号公報に記載）、スチリル誘導体（特開昭５６−２９２４５号公報、５８−１９８０４３号公報に記載）、カルバゾール誘導体（特開昭５８−５８５５２号公報に記載）、ピレン誘導体（特願平２−９４８１２号明細書に記載）などを使用することができる。
【００６８】
また、電荷輸送層には電荷輸送物質としての機能とバインダー樹脂の機能を持った高分子電荷輸送物質も良好に使用される。これら高分子電荷輸送物質から構成される電荷輸送層は耐摩耗性に優れたものである。高分子電荷輸送物質としては、公知の材料が使用できるが、特に、トリアリールアミン構造を主鎖および／または側鎖に含むポリカーボネートが良好に用いられる。中でも、下記（Ｉ）式〜（Ｘ）式で表わされる高分子電荷輸送物質が良好に用いられ、これらを以下に例示し、具体例を示す。
【００６９】
【化５】

式中、Ｒ₁，Ｒ₂，Ｒ₃はそれぞれ独立して置換もしくは無置換のアルキル基又はハロゲン原子、Ｒ₄は水素原子又は置換もしくは無置換のアルキル基、Ｒ₅，Ｒ₆は置換もしくは無置換のアリール基、ｏ，ｐ，ｑはそれぞれ独立して０〜４の整数、ｋ，ｊは組成を表わし、０．１≦ｋ≦１、０≦ｊ≦０．９、ｎは繰り返し単位数を表わし５〜５０００の整数である。Ｘは脂肪族の２価基、環状脂肪族の２価基、または下記一般式で表わされる２価基を表わす。
【００７０】
【化６】

式中、Ｒ₁₀₁，Ｒ₁₀₂は各々独立して置換もしくは無置換のアルキル基、アリール基またはハロゲン原子を表わす。ｌ，ｍは０〜４の整数、Ｙは単結合、炭素原子数１〜１２の直鎖状、分岐状もしくは環状のアルキレン基、−Ｏ−，−Ｓ−，−ＳＯ−，−ＳＯ₂−，−ＣＯ−，−ＣＯ−Ｏ−Ｚ−Ｏ−ＣＯ−（式中Ｚは脂肪族の２価基を表わす。）または、
【００７１】
【化７】

（式中、ａは１〜２０の整数、ｂは１〜２０００の整数、Ｒ₁₀₃，Ｒ₁₀₄は置換または無置換のアルキル基又はアリール基を表わす。）を表わす。ここで、Ｒ₁₀₁とＲ₁₀₂，Ｒ₁₀₃とＲ₁₀₄は、それぞれ同一でも異なってもよい。
【００７２】
【化８】

式中、Ｒ₇,Ｒ₈は置換もしくは無置換のアリール基、Ａｒ₁,Ａｒ₂,Ａｒ₃は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７３】
【化９】

式中、Ｒ₉，Ｒ₁₀は置換もしくは無置換のアリール基、Ａｒ₄，Ａｒ₅，Ａｒ₆は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７４】
【化１０】

式中、Ｒ₁₁，Ｒ₁₂は置換もしくは無置換のアリール基、Ａｒ₇，Ａｒ₈，Ａｒ₉は同一又は異なるアリレン基、ｐは１〜５の整数を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７５】
【化１１】

式中、Ｒ₁₃，Ｒ₁₄は置換もしくは無置換のアリール基、Ａｒ₁₀，Ａｒ₁₁，Ａｒ₁₂は同一又は異なるアリレン基、Ｘ₁，Ｘ₂は置換もしくは無置換のエチレン基、又は置換もしくは無置換のビニレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７６】
【化１２】

式中、Ｒ₁₅，Ｒ₁₆，Ｒ₁₇，Ｒ₁₈は置換もしくは無置換のアリール基、Ａｒ₁₃，Ａｒ₁₄，Ａｒ₁₅，Ａｒ₁₆は同一又は異なるアリレン基、Ｙ₁，Ｙ₂，Ｙ₃は単結合、置換もしくは無置換のアルキレン基、置換もしくは無置換のシクロアルキレン基、置換もしくは無置換のアルキレンエーテル基、酸素原子、硫黄原子、ビニレン基を表わし同一であっても異なってもよい。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７７】
【化１３】

式中、Ｒ₁₉，Ｒ₂₀は水素原子、置換もしくは無置換のアリール基を表わし，Ｒ₁₉とＲ₂₀は環を形成していてもよい。Ａｒ₁₇，Ａｒ₁₈，Ａｒ₁₉は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７８】
【化１４】

式中、Ｒ₂₁は置換もしくは無置換のアリール基、Ａｒ₂₀，Ａｒ₂₁，Ａｒ₂₂，Ａｒ₂₃は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００７９】
【化１５】

式中、Ｒ₂₂，Ｒ₂₃，Ｒ₂₄，Ｒ₂₅は置換もしくは無置換のアリール基、Ａｒ₂₄，Ａｒ₂₅，Ａｒ₂₆，Ａｒ₂₇，Ａｒ₂₈は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００８０】
【化１６】

式中、Ｒ₂₆，Ｒ₂₇は置換もしくは無置換のアリール基、Ａｒ₂₉，Ａｒ₃₀，Ａｒ₃₁は同一又は異なるアリレン基を表わす。Ｘ，ｋ，ｊおよびｎは、（Ｉ）式の場合と同じである。
【００８１】
電荷輸送層の膜厚は、５〜１００μｍ程度が適当であり、好ましくは、１０〜４０μｍ程度が適当である。
また、本発明において電荷輸送層中に可塑剤やレベリング剤を添加してもよい。可塑剤としては、ジブチルフタレート、ジオクチルフタレート等の一般に樹脂の可塑剤として使用されているものがそのまま使用でき、その使用量は、バインダ−樹脂１００重量部に対して０〜３０重量部程度が適当である。
【００８２】
次に、感光層が単層構成の場合について述べる。
キャスティング法等で単層感光層を設ける場合、多くは電荷発生物質と電荷輸送物質ならびにバインダー樹脂よりなる機能分離型のものが挙げられる。即ち、電荷発生物質ならびに電荷輸送物質には、前述の材料を用いることができる。
また、必要により可塑剤やレベリング剤を添加することもできる。更に、必要に応じて用いることのできるバインダー樹脂としては、先に電荷輸送層で挙げたバインダー樹脂をそのまま用いる他に、電荷発生層で挙げたバインダー樹脂を混合して用いてもよい。単層感光体の膜厚は、５〜１００μｍ程度が適当であり、好ましくは、１０〜４０μｍ程度が適当である。
【００８３】
本発明に用いられる電子写真感光体には、導電性支持体と感光層（積層タイプの場合には、電荷発生層）との間に下引き層を設けることができる。下引き層は、接着性を向上する、モワレなどを防止する、上層の塗工性を改良する、残留電位を低減するなどの目的で設けられる。下引き層は一般に樹脂を主成分とするが、これらの樹脂はその上に感光層を溶剤でもって塗布することを考えると、一般の有機溶剤に対して耐溶解性の高い樹脂であることが望ましい。このような樹脂としては、ポリビニルアルコール、カゼイン、ポリアクリル酸ナトリウム等の水溶性樹脂、共重合ナイロン、メトキシメチル化ナイロン、等のアルコール可溶性樹脂、ポリウレタン、メラミン樹脂、アルキッド−メラミン樹脂、エポキシ樹脂等、三次元網目構造を形成する硬化型樹脂などが挙げられる。また、酸化チタン、シリカ、アルミナ、酸化ジルコニウム、酸化スズ、酸化インジウム等で例示できる金属酸化物、あるいは金属硫化物、金属窒化物などの微粉末を加えてもよい。これらの下引き層は、前述の感光層のごとく適当な溶媒、塗工法を用いて形成することができる。
【００８４】
更に本発明の下引き層として、シランカップリング剤、チタンカップリング剤、クロムカップリング剤等を使用して、例えばゾル−ゲル法等により形成した金属酸化物層も有用である。
この他に、本発明の下引き層にはＡｌ₂Ｏ₃を陽極酸化にて設けたものや、ポリパラキシリレン（パリレン）等の有機物や、ＳｉＯ、ＳｎＯ₂、ＴｉＯ₂、ＩＴＯ、ＣｅＯ₂等の無機物を真空薄膜作製法にて設けたものも良好に使用できる。下引き層の膜厚は０〜８μｍが適当である。
【００８５】
また、本発明においては、耐環境性の改善のため、とりわけ感度低下、残留電位の上昇を防止する目的で酸化防止剤を添加することができる。酸化防止剤は、有機物を含む層ならばいずれに添加してもよいが、電荷輸送物質を含む層に添加すると良好な結果が得られる。
【００８６】
本発明に用いることができる酸化防止剤として、下記のものが挙げられる。
モノフェノール系化合物
２，６−ジ−ｔ−ブチル−ｐ−クレゾール、ブチル化ヒドロキシアニソール、２，６−ジ−ｔ−ブチル−４−エチルフェノール、ステアリル−β−（３，５−ジ−ｔ−ブチル−４−ヒドロキシフェニル）プロピオネートなど。
【００８７】
ビスフェノール系化合物
２，２’−メチレン−ビス−（４−メチル−６−ｔ−ブチルフェノール）、２，２’−メチレン−ビス−（４−エチル−６−ｔ−ブチルフェノール）、４，４’−チオビス−（３−メチル−６−ｔ−ブチルフェノール）、４，４’−ブチリデンビス−（３−メチル−６−ｔ−ブチルフェノール）など。
【００８８】
高分子フェノール系化合物
１，１，３−トリス−（２−メチル−４−ヒドロキシ−５−ｔ−ブチルフェニル）ブタン、１，３，５−トリメチル−２，４，６−トリス（３，５−ジ−ｔ−ブチル−４−ヒドロキシベンジル）ベンゼン、テトラキス−［メチレン−３−（３’，５’−ジ−ｔ−ブチル−４’−ヒドロキシフェニル）プロピオネート］メタン、ビス［３，３’−ビス（４’−ヒドロキシ−３’−ｔ−ブチルフェニル）ブチリックアッシド］グリコールエステル、トコフェロール類など。
【００８９】
パラフェニレンジアミン類
Ｎ−フェニル−Ｎ’−イソプロピル−ｐ−フェニレンジアミン、Ｎ，Ｎ’−ジ−ｓｅｃ−ブチル−ｐ−フェニレンジアミン、Ｎ−フェニル−Ｎ−ｓｅｃ−ブチル−ｐ−フェニレンジアミン、Ｎ，Ｎ’−ジ−イソプロピル−ｐ−フェニレンジアミン、Ｎ，Ｎ’−ジメチル−Ｎ，Ｎ’−ジ−ｔ−ブチル−ｐ−フェニレンジアミンなど。
【００９０】
ハイドロキノン類
２，５−ジ−ｔ−オクチルハイドロキノン、２，６−ジドデシルハイドロキノン、２−ドデシルハイドロキノン、２−ドデシル−５−クロロハイドロキノン、２−ｔ−オクチル−５−メチルハイドロキノン、２−（２−オクタデセニル）−５−メチルハイドロキノンなど。
【００９１】
有機硫黄化合物類
ジラウリル−３，３’−チオジプロピオネート、ジステアリル−３，３’−チオジプロピオネート、ジテトラデシル−３，３’−チオジプロピオネートなど。
【００９２】
有機燐化合物類
トリフェニルホスフィン、トリ（ノニルフェニル）ホスフィン、トリ（ジノニルフェニル）ホスフィン、トリクレジルホスフィン、トリ（２，４−ジブチルフェノキシ）ホスフィンなど。
【００９３】
これら化合物は、ゴム、プラスチック、油脂類などの酸化防止剤として知られており、市販品を容易に入手できる。本発明における酸化防止剤の添加量は、電荷輸送物質１００重量部に対して０．１〜１００重量部、好ましくは２〜３０重量部である。
【００９４】
本発明は次に、上記の電子写真感光体を用い、帯電、像露光及び転写を行なうことを特徴とする電子写真方法を提供する。そしてまた、上記の電子写真感光体を有すると共に、帯電手段、像露光手段及び転写手段を備えたことを特徴とする電子写真装置を提供する。さらに、上記の電子写真感光体と帯電手段、像露光手段、現像手段、転写手段及びクリーニング手段から選ばれた少なくとも一つの手段とを一体的に形成し、電子写真装置本体に着脱自在としたことを特徴とする電子写真装置用プロセスカートリッジを提供する。
図面に基づいて、この電子写真方法、電子写真装置及び電子写真装置用プロセスカートリッジについて説明する。
【００９５】
図３は、本発明の電子写真装置及び電子写真装置用プロセスカートリッジの概略図である。感光体（１１）はドラム状の形状を示しているが、シート状、エンドレスベルト状のものであってもよい。帯電チャージャ（１３）、転写前チャージャ（１７）、転写チャージャ（２０）、分離チャージャ（２１）、クリーニング前チャージャ（２３）には、コロトロン、スコロトロン、固体帯電器（ソリッド・ステート・チャージャー）、帯電ローラを始めとする公知の手段が用いられる。
転写手段には、一般に上記の帯電器が使用できるが、図に示されるように転写チャージャーと分離チャージャーを併用したものが効果的である。
【００９６】
画像露光部（１５）にはＬＤもしくはＬＥＤが用いられる。また、除電ランプ（１２）等の光源には、蛍光灯、タングステンランプ、ハロゲンランプ、水銀灯、ナトリウム灯、ＬＥＤ、ＬＤ、エレクトロルミネッセンス素子（ＥＬ）などの発光物全般を用いることができる。そして、所望の波長域の光のみを照射するために、シャープカットフィルター、バンドパスフィルター、近赤外カットフィルター、ダイクロイックフィルター、干渉フィルター、色温度変換フィルターなどの各種フィルターを用いることもできる。この時像露光部、書込光源のビーム系は１２００〜２４００ｄｐｉ相当の高解像度を達成するために１０〜３０μｍであることが好ましい。かかる光源等は、図３に示される工程の他に、光照射を併用した転写工程、除電工程、クリーニング工程、あるいは前露光などの工程を設けることにより、感光体に光が照射される。
【００９７】
現像ユニット（１６）により感光体（１１）上に現像されたトナーは、転写紙（１９）に転写されるが、全部が転写されるわけではなく、感光体（１１）上に残存するトナーも生ずる。このようなトナーは、ファーブラシ（２４）およびブレード（２５）により、感光体より除去される。クリーニングは、クリーニングブラシだけで行なわれることもあり、クリーニングブラシにはファーブラシ、マグファーブラシを始めとする公知のものが用いられる。
【００９８】
電子写真感光体に正（負）帯電を施し、画像露光を行なうと、感光体表面上には正（負）の静電潜像が形成される。これを負（正）極性のトナー（検電微粒子）で現像すれば、ポジ画像が得られるし、また正（負）極性のトナーで現像すれば、ネガ画像が得られる。かかる現像手段には、公知の方法が適用されるし、また、除電手段にも公知の方法が用いられる。
【００９９】
図４は、本発明の他の電子写真装置の概略図である。感光体（３１）は本発明の感光体であり、駆動ローラ（３２ａ），（３２ｂ）により駆動され、帯電器（３３）による帯電、光源（３４）による像露光、現像（図示せず）、帯電器（３５）を用いる転写、光源（３６）によるクリーニング前露光、ブラシ（３７）によるクリーニング、光源（３８）による除電が繰返し行なわれる。図５においては、感光体（２１）（勿論この場合は支持体が透光性である）に支持体側よりクリーニング前露光の光照射が行なわれる。
【０１００】
上記に図示した電子写真方法及び電子写真装置は、本発明における実施様態を例示したものであって、他の実施様態も可能である。例えば、図４においては、支持体側よりクリーニング前露光を行なっているが、これは感光層側から行なってもよく、また、像露光、除電光の照射を支持体側から行なってもよい。
また、光照射工程は、像露光、クリーニング前露光、除電露光が図示されているが、他に転写前露光、像露光のプレ露光、およびその他公知の光照射工程を設けて、感光体に光照射を行なうこともできる。
【０１０１】
このようにして行なう画像形成手段は、複写装置、ファクシミリ、プリンター内に固定して組み込まれていてもよいが、プロセスカートリッジの形態によりそれら装置内に組み込まれてもよい。プロセスカートリッジとは、感光体を内蔵し、他に帯電手段、露光手段、現像手段、転写手段、クリーニング手段、除電手段を含んだ１つの装置であり、また部品である。プロセスカートリッジの形状等については数多く挙げられるが、ここでは、図５にその１例を示す。このプロセスカートリッジは、本発明の電子写真感光体（２６）、帯電チャージャ（２７）、クリーニングブラシ（２８）、画像露光部（２９）、現像ローラ（３０）からなるものである。
【０１０２】
【実施例】
以下、本発明を実施例を挙げて説明するが、本発明が実施例により制限されるものではない。なお、部はすべて重量部である。
［第１群の本発明について］
参考例１
φ３０ｍｍアルミニウムシリンダー上に、下記組成の下引き層用塗工液、電荷発生層用塗工液、電荷輸送層用塗工液を順次、塗布乾燥することにより、３．５μｍの下引き層、０．２μｍの電荷発生層、２５μｍの電荷輸送層を形成した。その上に、アルミナボールを入れたボールミルを用いてキシレンと下記有機フィラーを１２時間分散し、そこに下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合して表面層用塗工液１を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１０３】
〔下引き層用塗工液〕
アルキッド樹脂 ６部
（ベッコゾール１３０７−６０−ＥＬ、大日本インキ化学工業製）
メラミン樹脂 ４部
（スーパーベッカミンＧ−８２１−６０、大日本インキ化学工業製）
酸化チタン（ＣＲＥＬ、石原産業社製） ４０部
メチルエチルケトン ２００部
【０１０４】
〔電荷発生層用塗工液〕
オキソチタニウムフタロシアニン顔料 ２部
ポリビニルブチラール（ＵＣＣ：ＸＹＨＬ） ０．２部
テトラヒドロフラン ５０部
【０１０５】
〔電荷輸送層用塗工液〕
ポリカーボネート樹脂
（Ｚポリカ、帝人化成社製、Ｍｖ５万） １０部
ジクロルメタン １００部
１％シリコーンオイル
（ＫＦ５０、信越シリコーン社製）ジクロルメタン溶液 １部
下記構造式（ＸＩ）で表わされる電荷輸送物質 ３部
【０１０６】
【化１７】

【０１０７】
〔表面層用塗工液１〕
球形メラミン（エポスターＳ、日本触媒製） ２部
キシレン ６０部
トルエン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１０８】
参考例２
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてシクロヘキサノンと下記有機フィラーを１２時間分散し、そこに下記バインダー樹脂をテトラヒドロフランに溶解し、上記分散液に添加、混合して表面層用塗工液２を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１０９】
〔表面層用塗工液２〕
球形メラミン（エポスターＳ、日本触媒製） ２部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１１０】
参考例３
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてシクロペンタノンと下記有機フィラーを１２時間分散し、そこに下記バインダー樹脂と電荷輸送物質（ＸＩ）式をテトラヒドロフランに溶解し、上記分散液に添加、混合して表面層用塗工液３を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１１１】
〔表面層用塗工液３〕
球形メラミン（エポスターＳ、日本触媒製） ２部
シクロペンタノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸＩ）で表わされる電荷輸送物質 ３部
【０１１２】
参考例４
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてテトラヒドロフラン６０部と下記有機フィラーを１２時間分散し、そこに構造式（ＸII）の高分子電荷輸送物質をテトラヒドロフラン１２０部とキシレン６０部に溶解し、上記分散液に添加、混合して表面層用塗工液４を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１１３】
〔表面層用塗工液４〕
球形メラミン（エポスターＳ、日本触媒製） ２部
テトラヒドロフラン １８０部
キシレン ６０部
下記構造式（ＸII）の高分子電荷輸送物質 ８部
【０１１４】
【化１８】

【０１１５】
参考例５
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてシクロヘキサノンと下記無機顔料を１２時間分散し、そこに下記バインダー樹脂と電荷輸送物質（ＸI）をテトラヒドロフランに溶解し、上記分散液に添加、混合して表面層用塗工液５を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１１６】
〔表面層用塗工液５〕
酸化亜鉛（Ｓａｚｅｘ４０００、堺化学製） ２部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸI）で表わされる電荷輸送物質 ３部
【０１１７】
参考例６
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてシクロペンタノンと下記シリカを１２時間分散し、そこに下記バインダー樹脂と電荷輸送物質（ＸI）を１，３−ジオキソランに溶解し、上記分散液に添加、混合して表面層用塗工液６を作成し、この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１１８】
〔表面層用塗工液６〕
シリカ（ＫＭＰＸ−１００、信越化学工業製） ２部
シクロペンタノン ６０部
１，３−ジオキソラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸI）で表わされる電荷輸送物質 ３部
【０１１９】
参考例７
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、アルミナボールを入れたボールミルを用いてシクロヘキサノンと下記アルミナと下記ポリカルボン酸を１２時間分散し、そこに下記バインダー樹脂と電荷輸送物質（ＸI）をテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液７を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表１に示す。
【０１２０】
〔表面層用塗工液７〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
オレイン酸 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸI）で表わされる電荷輸送物質 ３部
【０１２１】
【表１】

【０１２２】
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降
【０１２３】
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測した。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１２４】
参考比較例１
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、参考例１と同様の有機顔料とキシレンおよび、参考例１と同様のバインダー樹脂とトルエンを加えて分散を行ない、表面層用塗工液（参比１）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表２に示す。
【０１２５】
参考比較例２
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、参考例５と同様の無機顔料とシクロヘキサノンおよび、参考例５と同様のバインダー樹脂、電荷輸送物質とテトラヒドロフランを加えて分散を行ない、表面層用塗工液（参比２）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表２に示す。
【０１２６】
参考比較例３
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、参考例７と同様のアルミナ、ポリカルボン酸、シクロヘキサノンおよび、参考例７と同様のバインダー樹脂、電荷輸送物質と１，３−ジオキソランを加えて分散を行ない、表面層用塗工液（参比３）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
参考例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表２に示す。
【０１２７】
参考比較例４
参考例１と同様に下引き層、電荷発生層、電荷輸送層を設け、表面層を積層しない電子写真感光体を得た。
参考例１と同様に感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層（電荷輸送層）の摩耗減量を表２に示す。
【０１２８】
【表２】

【０１２９】
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降…×
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測する。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１３０】
［第２群の本発明について］
実施例１
φ３０ｍｍアルミニウムシリンダー上に、下記組成の下引き層用塗工液、電荷発生層用塗工液、電荷輸送層用塗工液を順次、塗布乾燥することにより、３．５μｍの下引き層、０．２μｍの電荷発生層、２５μｍの電荷輸送層を形成した。
その上に、キシレンと下記有機フィラーと分散剤（メタクリロキシ変性シリコーン）をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで２時間粉砕して分散した。粉砕前の液温度は２０℃、粉砕終了後の液温度は３５℃で、粉砕工程で１５℃の温度上昇があった。そこに下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合して表面層用塗工液８を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１３１】
〔下引き層用塗工液〕
アルキッド樹脂 ６部
（ベッコゾール１３０７−６０−ＥＬ、大日本インキ化学工業製）
メラミン樹脂 ４部
（スーパーベッカミンＧ−８２１−６０、大日本インキ化学工業製）
酸化チタン（ＣＲＥＬ、石原産業社製） ４０部
メチルエチルケトン ２００部
【０１３２】
〔電荷発生層用塗工液〕
オキソチタニウムフタロシアニン顔料 ２部
ポリビニルブチラール（ＵＣＣ：ＸＹＨＬ） ０．２部
テトラヒドロフラン ５０部
【０１３３】
〔電荷輸送層用塗工液〕
ポリカーボネート樹脂
（Ｚポリカ、帝人化成社製、Ｍｖ５万） １０部
ジクロルメタン １００部
１％シリコーンオイル
（ＫＦ５０、信越シリコーン社製）ジクロルメタン溶液 １部
下記構造式（ＸIII）で表わされる電荷輸送物質 ３部
【０１３４】
【化１９】

【０１３５】
〔表面層用塗工液８〕
球形メラミン（エポスターＳ、日本触媒製） ２部
メタクリロキシ変性シリコーン
（サイラープレーンＦＭ０７２５、チッソ社製） ０．１部
キシレン ６０部
トルエン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１３６】
実施例２
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、キシレンと下記有機フィラーと分散剤（ポリエステル樹脂）をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで２時間粉砕して分散した。粉砕前の液温度は２５℃、粉砕終了後の液温度は３８℃で、粉砕工程で１３℃の温度上昇があった。そこに下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合して表面層用塗工液９を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１３７】
〔表面層用塗工液９〕
球形メラミン（エポスターＳ、日本触媒製） ２部
ポリエステル樹脂 ０．０５部
キシレン ６０部
トルエン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１３８】
実施例３
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、シクロヘキサノンと下記有機フィラーと分散剤（ポリエステル樹脂）をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで２時間粉砕して分散した。粉砕前の液温度は２０℃、粉砕終了後の液温度は３３℃で、粉砕工程で１３℃の温度上昇があった。そこに下記バインダー樹脂をテトラヒドロフランに溶解して上記分散液に添加、混合して表面層用塗工液１０を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１３９】
〔表面層用塗工液１０〕
球形メラミン（エポスターＳ、日本触媒製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１４０】
実施例４
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、シクロペンタノンと下記無機顔料と分散剤（ポリエステル樹脂）をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで２時間粉砕して分散した。粉砕前の液温度は２０℃、粉砕終了後の液温度は３５℃で、粉砕工程で１５℃の温度上昇があった。そこに下記バインダー樹脂をテトラヒドロフランに溶解して上記分散液に添加、混合して表面層用塗工液１１を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１４１】
〔表面層用塗工液１１〕
酸化亜鉛（Ｓａｚｅｘ４０００、堺化学製） ２部
ポリエステル樹脂 ０．０５部
シクロペンタノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１４２】
実施例５
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、シクロペンタノンとシリカと分散剤（オレイン酸）をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで２時間粉砕して分散した。粉砕前の液温度は２０℃、粉砕終了後の液温度は３４℃で、粉砕工程で１４℃の温度上昇があった。そこに下記バインダー樹脂を１，３−ジオキソランに溶解して上記分散液に添加、混合して表面層用塗工液１２を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１４３】
〔表面層用塗工液１２〕
シリカ（ＫＭＰＸ−１００、信越化学工業製） ２部
オレイン酸 ０．０５部
シクロペンタノン ６０部
１，３−ジオキソラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１４４】
実施例６
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、φ２０ｍｍのアルミナボールを入れたボールミルを用いてシクロヘキサノンと下記アルミナと分散剤（ポリエステル樹脂）を１２時間粉砕して分散した。粉砕前の液温度は１６℃、粉砕終了後の液温度は２２℃で、粉砕工程で６℃の温度上昇があった。そこに下記バインダー樹脂とテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液１３を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１４５】
〔表面層用塗工液１３〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１４６】
実施例７
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、φ５ｍｍのアルミナボールを入れたボールミルを用いてシクロヘキサノンと下記アルミナ分散剤（ポリエステル樹脂）を１２時間粉砕して分散した。粉砕前の液温度は２５℃、粉砕終了後の液温度は２８℃で、粉砕工程で３℃の温度上昇があった。そこに下記バインダー樹脂をテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液１４−１を作成した。
次に、下記バインダー樹脂と式（ＸIII）で表わされる電荷輸送物質３部をテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液１４−２を作成した。
更に、式（ＸIV）で表わされる高分子電荷輸送物質８部をテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液１４−３を作成した。
これらの液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表３に示す。
【０１４７】
〔表面層用塗工液１４−１〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１４８】
〔表面層用塗工液１４−２〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸIII）で表わされる電荷輸送物質 ３部
【０１４９】
〔表面層用塗工液１４−３〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
テトラヒドロフラン １８０部
下記構造式（ＸIV）で表わされる電荷輸送物質 ８部
【０１５０】
【化２０】

【０１５１】
【表３】

【０１５２】
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降
【０１５３】
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測した。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１５４】
比較例１
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、実施例１と同様のキシレンと有機フィラーと分散剤をφ０．２ｍｍのアルミナボールを入れたガラス容器を用いてペイントシェーカーで３時間粉砕して分散した。粉砕前の液温度は２０℃、粉砕終了後の液温度は５０℃で、粉砕工程で３０℃の温度上昇があった。そこに実施例１と同様のバインダー樹脂をトルエンに溶解して上記分散液に添加、混合して表面層用塗工液（比１）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表４に示す。
【０１５５】
比較例２
実施例４と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、実施例４と同様のシクロペンタノンと無機顔料と分散剤をφ０．２ｍｍのアルミナボールを入れたビーズミルを用いて１６℃の水で冷却しながら１時間粉砕して分散した。粉砕前の液温度は１６℃、粉砕終了後の液温度は３８℃で、粉砕工程で２２℃の温度上昇があった。そこに実施例４と同様のバインダー樹脂をテトラヒドロフランに溶解して上記分散液に添加、混合して表面層用塗工液（比２）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表４に示す。
【０１５６】
比較例３
実施例７と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、実施例７と同様のシクロヘキサノンとアルミナと分散剤をガラス製三角フラスコに入れ、超音波分散器を用いて水道水を流しながら２時間粉砕して分散した。粉砕前の液温度は２５℃、粉砕終了後の液温度は６２℃で、粉砕工程で３８℃の温度上昇があった。そこに実施例７と同様のバインダー樹脂と式（ＸIII）で表わされる電荷輸送物質３部をテトラヒドロフランに溶解して、上記分散液に添加、混合して表面層用塗工液（比３）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
実施例１と同様に表面層用塗工液の体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表４に示す。
【０１５７】
比較例４
実施例１と同様に下引き層、電荷発生層、電荷輸送層を設け、表面層を積層しない電子写真感光体（比４）を得た。
実施例１と同様に感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層（電荷輸送層）の摩耗減量を表４に示す。
【０１５８】
【表４】

【０１５９】
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降…×
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測する。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１６０】
［第３群の本発明について］
参考例８
φ３０ｍｍアルミニウムシリンダー上に、下記組成の下引き層用塗工液、電荷発生層用塗工液、電荷輸送層用塗工液を順次、塗布乾燥することにより、３．５μｍの下引き層、０．２μｍの電荷発生層、２５μｍの電荷輸送層を形成した。
その上に、下記有機フィラーとキシレンをφ２ｍｍのアルミナボールを入れたガラス容器を用いて、ボールミルで１２時間分散した。次に、下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合することで表面層用塗工液１５を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１６１】
〔下引き層用塗工液〕
アルキッド樹脂 ６部
（ベッコゾール１３０７−６０−ＥＬ、大日本インキ化学工業製）
メラミン樹脂 ４部
（スーパーベッカミンＧ−８２１−６０、大日本インキ化学工業製）
酸化チタン（ＣＲＥＬ、石原産業社製） ４０部
メチルエチルケトン ２００部
【０１６２】
〔電荷発生層用塗工液〕
オキソチタニウムフタロシアニン顔料 ２部
ポリビニルブチラール（ＵＣＣ：ＸＹＨＬ） ０．２部
テトラヒドロフラン ５０部
【０１６３】
〔電荷輸送層用塗工液〕
ポリカーボネート樹脂
（Ｚポリカ、帝人化成社製、Ｍｖ５万） １０部
ジクロルメタン １００部
１％シリコーンオイル
（ＫＦ５０、信越シリコーン社製）ジクロルメタン溶液 １部
下記構造式（ＸＶ）で表わされる電荷輸送物質 ３部
【０１６４】
【化２１】

【０１６５】
〔表面層用塗工液１５〕
球形メラミン（エポスターＳ、日本触媒製） ２部
キシレン １００部
トルエン １００部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１６６】
参考例９
トルエン１００部に塩化亜鉛を０．０００５部溶解して、塩素イオンを２ｐｐｍ以上含有するトルエンを得た。このトルエンにシリカゲルを２０部加えて１時間撹拌後、１０μｍのテフロン（登録商標）製フィルターを用いて濾過することでイオン除去処理したトルエンを得た。
次に、参考例８と同様の下引き層、電荷発生層、電荷輸送層を設け、その上に参考例８と同様の有機フィラーとキシレンを参考例８と同様の方法で分散した。さらに、参考例８と同様のバインダー樹脂を上記トルエンに溶解してフィラー分散液に添加、混合することで表面層用塗工液１６を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１６７】
参考例１０
参考例９と同様の方法で塩素イオンを２ｐｐｍ以上含有するトルエンを作成した。このトルエンに、参考例２のシリカゲルの代わりにフロリジル（関東化学製）を用いて、参考例９と同様の方法でイオン除去処理を施したトルエンを得た。
次に、参考例９と同様の方法で表面層用塗工液１７を作成し、この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１６８】
参考例１１
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、下記有機フィラーと分散剤（メタクリロキシ変性シリコーン）とキシレンを参考例８と同様の方法で分散した。次に、下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合することで表面層用塗工液１８を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１６９】
〔表面層用塗工液１８〕
球形メラミン（エポスターＳ、日本触媒製） ２部
メタクリロキシ変性シリコーン
（サイラープレーンＦＭ０７２５、チッソ社製） ０．０５部
キシレン １００部
トルエン １００部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１７０】
参考例１２
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、分散剤をメタクリロキシ変性シリコーンからポリエステル樹脂に代えた以外は参考例１１と同じ方法で表面層用塗工液１９を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１７１】
〔表面層用塗工液１９〕
球形メラミン（エポスターＳ、日本触媒製） ２部
ポリエステル樹脂 ０．０５部
キシレン １００部
トルエン １００部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１７２】
参考例１３
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、有機フィラーを無機顔料に代えた以外は参考例１２と同じ方法で表面層用塗工液２０を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１７３】
〔表面層用塗工液２０〕
酸化亜鉛（Ｓａｚｅｘ４０００、堺化学製） ２部
ポリエステル樹脂 ０．０５部
キシレン １００部
トルエン １００部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１７４】
参考例１４
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、下記アルミナと分散剤（ポリエステル樹脂）とシクロヘキサノンを参考例８と同じ方法で分散した。次に、下記バインダー樹脂をトルエンに溶解して上記分散液に添加、混合することで表面層用塗工液２１を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１７５】
〔表面層用塗工液２１〕
酸化チタン（ＣＲ−ＥＬ、石原産業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
トルエン １４０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
【０１７６】
参考例１５
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、下記アルミナと分散剤（ポリエステル樹脂）とシクロヘキサノンを参考例８と同じ方法で分散した。次に、下記バインダー樹脂と構造式（ＸVI）で表わされる電荷輸送物質をトルエンに溶解して上記分散液に添加、混合することで表面層用塗工液２２を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１７７】
〔表面層用塗工液２２〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
トルエン １４０部
ポリカーボネート樹脂
（Ｚポリカ、帝人化成製、Ｍｖ５万） ５部
構造式（ＸVI）で表わされる電荷輸送物質 ３部
【０１７８】
参考例１６
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、下記アルミナと分散剤（ポリエステル樹脂）とシクロヘキサノンを参考例８と同じ方法で分散した。次に、構造式（ＸVI）で表される高分子電荷輸送物質をトルエンに溶解して上記分散液に添加、混合することで表面層用塗工液２３を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、本発明の電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表５に示す。
【０１７９】
〔表面層用塗工液２３〕
アルミナ（ＡＫＰ−５０、住友化学工業製） ２部
ポリエステル樹脂 ０．０５部
シクロヘキサノン ６０部
トルエン １４０部
下記構造式（ＸVI）で表わされる高分子電荷輸送物質 ８部
【０１８０】
【化２２】

【０１８１】
【表５】

【０１８２】
塩素イオン濃度は、塗工液に等量のイオン交換水を加え、振とう後、放置して、分離した水をイオンクロマトグラフで半定量測定を行なった。
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降
【０１８３】
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測した。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１８４】
参考比較例５
参考例９と同様の方法で塩素イオンを２ｐｐｍ以上含有するトルエンを作成した。次に、参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、参考例８と同様の有機フィラーと分散剤とキシレンを参考例８と同様の方法で分散した。さらに、参考例８と同様のバインダー樹脂を上記トルエンに溶解してフィラー分散液に添加、混合することで表面層用塗工液（参比５）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表６に示す。
【０１８５】
参考比較例６
参考例９と同様の方法で塩素イオンを２ｐｐｍ以上含有するトルエンを作成した。次に、参考例８と同様に下引き層、電荷発生層、電荷輸送層を設けた上に、参考例１５と同様のアルミナと分散剤とシクロヘキサノンを参考例１５と同様の方法で分散した。さらに、参考例１５と同様のバインダー樹脂と電荷輸送物質を上記トルエンに溶解してフィラー分散液に添加、混合することで表面層用塗工液（参比６）を作成した。この液をスプレーで塗工して約３．０μｍの表面層を設け、乾燥後、電子写真感光体を得た。
表面層用塗工液の塩素イオン濃度、体積平均粒径、沈降試験結果と、表面層を設けた感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層の摩耗減量を表６に示す。
【０１８６】
参考比較例７
参考例８と同様に下引き層、電荷発生層、電荷輸送層を設け、表面層を積層しない電子写真感光体（参比７）を得た。
感光体の初期画像及び１万枚通紙ランニング後の画像評価結果、表面層（電荷輸送層）の摩耗減量を表６に示す。
【０１８７】
【表６】

【０１８８】
塩素イオン濃度は、塗工液に等量のイオン交換水を加え、振とう後、放置して、分離した水をイオンクロマトグラフで半定量測定を行なった。
体積平均粒径は堀場製作所製ＣＡＰＡ７００で計測した。
沈降性評価基準
◎：２日静置して分散粒子の沈降なし
○：１日静置して分散粒子の沈降なし
△：１日静置して分散粒子が一部沈降
×：１日静置して分散粒子が全部沈降
【０１８９】
感光体を（株）リコー製複写機イマジオＭＦ２００に装着し、暗部電位８００Ｖ、明部電位１００Ｖに設定し画像（初期）を出し、次に１万枚の通紙試験を行なった後、同様の方法で画像（１万枚）と摩耗量（１万枚通紙前後の膜厚差）を計測した。
膜厚は渦電流式膜厚計フィシャー社製フィシャーコープＭＭＳで測定した。
【０１９０】
【発明の効果】
以上、詳細且つ具体的な説明より明らかなように、第１群の本発明の電子写真感光体の製造方法によれば、小粒径にフィラーを分散することができるため、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより、高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ケトン類、エーテル類を用いることでより分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、電荷輸送物質を用いることで、高感度で耐久性に優れ、繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、高分子電荷輸送物質を用いることで、高感度でより耐久性に優れ、繰返し使用に対して安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、無機顔料を用いることで耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、シリカ、アルミナ、酸化チタンを用いることでさらに耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ポリエステル樹脂、アクリル樹脂、あるいはそれらの構造を含む共重合体、ポリカルボン酸、有機脂肪酸が分散剤として機能するため、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となるという優れた効果を奏する。
また、第２群の本発明の電子写真感光体の製造方法によれば、粉砕工程での温度上昇を２０℃以下に抑えることで、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより、高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ポリエステル樹脂、アクリル樹脂、あるいはそれらの構造を含む共重合体、ポリカルボン酸、有機脂肪酸が分散剤として良好に機能するため、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ケトン類、エーテル類を用いることでより分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、無機顔料を用いることで耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、シリカ、アルミナ、酸化チタンを用いることでさらに耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ボールミルを用いることで粉砕時の温度上昇を小さく抑えることができるため、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、ボールミルにφ１ｍｍ以上φ１０ｍｍ以下のアルミナボールを用いることで粉砕時の温度上昇をより小さく抑えることができるため、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、電荷輸送物質を用いることで、高感度で耐久性に優れ、繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、高分子電荷輸送物質を用いることで、高感度でより耐久性に優れ、繰返し使用に対して安定な高画質画像を作像できる感光体の提供が可能となるという優れた効果を奏する。
さらに、第３群の本発明の電子写真感光体の製造方法によれば、塩素イオン濃度を１ｐｐｍ以下に規定することで分散安定性に優れたフィラー含有表面層用塗工液が作成できるため、高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、イオン吸着材を用いて溶媒中の塩素イオン濃度を１ｐｐｍ以下に低減することにより、分散安定性に優れたフィラー含有表面層用塗工液が作成できるため、高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、イオン吸着剤として、活性白土、フロリジル、塩基性アルミナを用いることでより多くの塩素イオンを除去することができ、分散安定性に優れたフィラー含有表面層用塗工液が作成できるため、高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散剤を添加することで、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散剤としてポリエステル樹脂、アクリル樹脂、あるいはそれらの構造を含む共重合体、モノカルボン酸、有機脂肪酸は良好に機能するため、より分散安定性に優れたフィラー含有表面層用塗工液を作成でき、これを用いることにより高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、無機顔料を用いることで耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、シリカ、アルミナ、酸化チタンを用いることでさらに耐摩耗性が向上するため、より高耐久で繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、電荷輸送物質を用いることで、高感度で耐久性に優れ、繰返し使用に対し安定な高画質画像を作像できる感光体の提供が可能となる。また、分散安定性に優れたフィラー含有表面層用塗工液を作成でき、高分子電荷輸送物質を用いることで、高感度でより耐久性に優れ、繰返し使用に対して安定な高画質画像を作像できる感光体の提供が可能となるという優れた効果を奏する。
【図面の簡単な説明】
【図１】本発明の電子写真感光体の構成例を表わす断面図である。
【図２】本発明の電子写真感光体の他の構成例を表わす断面図である。
【図３】本発明の電子写真装置及び電子写真装置用プロセスカートリッジの概略図である。
【図４】本発明の他の電子写真装置を示す概略図である。
【図５】本発明の他のプロセスカートリッジを示す概略図である。
【符号の説明】
１ 導電性支持体
２ 感光層
３ 表面層
４ 電荷発生層
５ 電荷輸送層
１１ 感光体
１２ 除電ランプ
１３ 帯電チャージャ
１４ イレーサ
１５ 画像露光部
１６ 現像ユニット
１７ 転写前チャージャ
１８ レジストローラ
１９ 転写紙
２０ 転写チャージャ
２１ 分離チャージャ
２２ 分離爪
２３ クリーニングチャージャ
２４ ファーブラシ
２６ 感光体
２７ 帯電チャージャ
２８ クリーニングブラシ
２９ 画像露光部
３０ 現像ローラ
３１ 感光体
３２ａ 駆動ローラ
３２ｂ 駆動ローラ
３３ 帯電チャージャ
３４ 像露光源
３５ 転写チャージャ
３６ クリーニング前露光
３７ クリーニングブラシ
３８ 除電光源[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an electrophotographic photosensitive member in which a filler is contained in the surface layer of the electrophotographic photosensitive member, an electrophotographic photosensitive member, and an electrophotographic apparatus equipped with the electrophotographic photosensitive member. The present invention relates to a durable electrophotographic photosensitive member and an electrophotographic apparatus equipped with the electrophotographic photosensitive member.
The electrophotographic photosensitive member of the present invention and the electrophotographic process using the same are applied to a copying machine, a facsimile, a laser printer, a direct digital plate making machine, and the like.
[0002]
[Prior art]
As a conventional technique, Japanese Patent Application Laid-Open No. 07-110588 discloses that a coating solution for a charge generation layer having excellent dispersion stability can be obtained by using an alicyclic ketone for dispersing an azo pigment and adding a binder after the dispersion. JP-A-11-038652 discloses that a coating solution for a charge generation layer having excellent dispersion stability can be obtained by adding a binder after dispersion without adding a binder to the dispersion of the organic charge generation pigment. JP-A-08-006271 describes that a charge generation layer coating solution having excellent dispersion stability can be obtained by dispersing a charge generation material in a hydrophobic dispersant and a binder resin. JP-A-06-332219 describes that a coating solution for a surface layer can be obtained by pulverizing and dispersing a fluororesin powder and a solvent using high-pressure liquid collision.
[0003]
2. Description of the Related Art In recent years, there has been a demand for higher durability of photoconductors as electrophotographic copying machines, electrophotographic printers, and the like increase in speed, size, and image quality. In an electrophotographic process, a photoreceptor is deteriorated by mechanical and chemical actions in repeated processes of charging, exposure, development, transfer, and cleaning. Mechanical deterioration causes wear and scratches on the photoconductor, and chemical deterioration causes binder resin due to ozone generated, oxidation deterioration of the charge transfer material, and deterioration of image quality due to deposits. In addition, as described above, the diameter of the photoconductor is reduced with the increase in speed and size, and the use conditions in the electrophotographic process become severe. In particular, a rubber blade is used in the cleaning unit, and the rubber hardness is required for sufficient cleaning. As a result, the increase in the contact pressure and the contact pressure are forced, which promotes the wear of the photoconductor, resulting in potential fluctuations and sensitivity fluctuations, resulting in a loss of color balance between abnormal images and color images, and problems in color reproducibility. This causes a malfunction. For this purpose, a technique for adding a filler to the outermost surface of the photoreceptor has been proposed.
[0004]
As a method for adding a filler to the surface layer, a coating liquid in which a filler is dispersed in a binder resin and a solvent, or a coating liquid in which a filler is dispersed in a binder resin, a charge transfer substance, and a solvent are prepared, and a dip coating method is used. It is generally formed by applying and drying on the charge transport layer using a coating method such as a ring coating method, a spray coating method, or a roll coating method. The surface layer including the filler thus formed is required to have a uniform film thickness and a uniform filler concentration, and when mounted on a copying machine, a printer, etc., the non-uniform film corresponds to the film thickness unevenness in the halftone image. There arises a problem that uneven shading occurs. In addition, when the filler particle diameter in the film increases to 2 μm or more, the coating film becomes rough and the light transmittance decreases, so that sufficient sensitivity cannot be obtained, and the gradation of the image is deteriorated, the background stains, etc. A problem occurs. Problems such as coating film non-uniformity and filler particle agglomeration are caused by poor filler dispersion in the coating solution, and can be solved by improving the dispersibility of the filler in the coating solution. it can.
[0005]
The methods described in Japanese Patent Application Laid-Open Nos. 07-110587 and 11-038652 are obtained by dispersing an organic charge generating pigment in a solvent and then adding a binder resin solution. These are defined in the range of the dispersion of the specific organic charge generating pigment, which is different from the invention intended for the dispersion of the filler added to the surface layer as in the present invention.
In addition, the method described in Japanese Patent Application Laid-Open No. 08-006271 is intended to increase the dispersion stability by adsorbing the dispersant on the particle surface of the charge generation material, and is added to the surface layer as in the present invention. The composition and structure are completely different from the dispersant adsorbed on the filler.
In addition, the method described in JP-A-06-332219 relates to the dispersion of the surface layer coating solution containing a filler. When adding a binder resin to the surface layer, the filler and the binder resin are mixed. Since the binder resin acts as a cushion that prevents the filler particles from being pulverized, the pulverization efficiency is extremely poor, which is different from the present invention in which the dispersion is performed without adding the binder resin.
[0006]
On the other hand, Japanese Patent Application Laid-Open No. 08-044086 describes that a coating solution for a photosensitive layer having excellent dispersibility is obtained by improving the grinding efficiency of a ball mill, and Japanese Patent Application Laid-Open No. 11-249324 discloses a bead mill. In JP-A-2000-126638, it is described that by eliminating pre-dispersion in JP-A-2000-126638, a dispersibility can be improved by using a media of 2 mm or less in a bead mill. It is described that an excellent coating solution for a charge generation layer is obtained. Japanese Patent Application Laid-Open No. 06-043672 discloses a charge generation layer excellent in dispersibility by pulverization using a ball of 0.4 to 0.8 mm. JP-A-07-289870 describes a dispersion method by wet high-pressure atomization, and JP-A-06-332219 discloses a high-pressure collision. By using the pulverization method, it is described that to obtain a surface layer coating liquid having excellent dispersibility.
[0007]
The method described in Japanese Patent Laid-Open No. 08-044086 described above improves the grinding efficiency using a ball mill, and the method described in Japanese Patent Laid-Open No. 11-249324 improves the grinding efficiency using a bead mill. Yes, the method described in JP-A No. 2000-126638 improves the grinding efficiency by using a ball of 2 mm or less in the bead mill, and the method described in JP-A No. 06-043672 is 0.4 for the ball mill. The grinding efficiency is improved by using a ball of ~ 0.8 mm. However, the present invention suppresses heat generation due to impact or friction to 20 ° C. or less by suppressing pulverization efficiency, and is an invention from a completely opposite viewpoint. Furthermore, both of these inventions have a range defined for the dispersion of specific organic charge generating pigments, which is completely different from the invention intended for dispersing fillers added to the surface layer as in the present invention.
[0008]
Further, the method described in Japanese Patent Application Laid-Open No. 07-289870 is pulverized by high-pressure atomization, and the method described in Japanese Patent Application Laid-Open No. 06-332219 is performed by high-pressure liquid collision. However, when these methods are used, the amount of heat generated by impact, friction, etc. is very large, and problems such as poor dispersion due to the inability of the dispersant to adsorb on the filler surface due to temperature rise occur. Further, the method described in JP-A-07-289870 is limited to the dispersion of a specific organic charge generating pigment, and the invention is intended for dispersion of a filler added to the surface layer as in the present invention. Is completely different.
[0009]
Further, Patent Registration No. 2946174 describes an electrophotographic photosensitive member containing 0.1 to 10 ppm of transition metal atoms in the surface layer, and Japanese Patent Application Laid-Open No. 08-146642 includes silica particles in the outermost layer. In addition, there is described an electrophotographic photoreceptor in which the concentration of Al, Ca, and Fe in silica particles is regulated to 1000 ppm or less. Japanese Patent Application Laid-Open Nos. 09-179316 and 09-265202 describe a binder resin for a charge generation layer. An electrophotographic photoreceptor in which residual Na ions are 500 ppm or less is described, and JP-A-11-194520 describes an electrophotographic photoreceptor in which Na ions remaining in the binder resin of the undercoat layer is 40 ppm or less. JP 2000-003049 A describes a method for removing organic acid from a charge transport layer coating solution using an adsorbent. To have.
[0010]
The one described in the above-mentioned Patent Registration No. 0946174 is that the surface layer contains 0.1 to 10 ppm of transition metal atoms, and the one described in JP-A-08-146642 has silica particles in the outermost layer. In addition, the concentration of Al, Ca, and Fe in the silica particles is regulated to 1000 ppm or less, and the element concentration in the same surface layer is regulated, but the target element is completely different from the present invention.
[0011]
In addition, those described in JP-A Nos. 09-179316 and 09-265202 regulate Na ions remaining in the binder resin of the charge generation layer to 500 ppm or less, and JP-A No. 11-194520. In Table 1, Na ions remaining in the binder resin of the undercoat layer are regulated to 40 ppm or less, and the target layer and elements are completely different from those of the present invention.
Japanese Patent Laid-Open No. 2000-003049 discloses a method in which an organic acid is removed from a coating liquid for a charge transport layer using an adsorbent. It is different from the invention.
[0012]
[Problems to be solved by the invention]
An object of the present invention is to use a method for producing a highly durable electrophotographic photoreceptor comprising a laminate of a surface layer composed of a binder resin and a filler or a binder resin, a filler and a charge transport material on the photosensitive layer, and a method for producing the same. The object is to provide a highly durable electrophotographic photoreceptor.
[0013]
[Means for Solving the Problems]
According to the first group of the present invention, a photosensitive layer is laminated directly or via an intermediate layer on a conductive support, and at least a binder resin and a filler, or a binder resin, a filler, and a charge transport material are placed on the photosensitive layer. In the method for producing a photoreceptor in which the surface layer to be contained is laminated, by dispersing the filler in the solvent without adding the binder resin, the crushing force in the disperser is not softened like the cushion. For this reason, the pulverization efficiency is increased, and the particle size of the filler can be reduced in a short time, so that the dispersion stability can be improved. In addition, since the filler concentration at the time of dispersion can be increased by the amount excluding the binder resin, the pulverization efficiency is further improved and the productivity can be increased. In particular, by using ketones or ethers as the dispersion solvent, the wettability with the filler is improved, so that the filler can be further reduced in particle size, and the dispersion stability can be further improved.
[0014]
By including the charge transport material in the filler-containing surface layer, it is possible to suppress an increase in the bright part potential, which is considered to be caused by poor charge transportability, and thus it is possible to obtain an image free from background stains. Further, when a polymer charge transport material is used, the strength of the film is improved, so that the wear resistance can be improved.
[0015]
As the filler, the inorganic pigment has higher hardness and higher wear resistance than the organic pigment. Among inorganic pigments, silica, alumina, and titanium oxide are materials that are particularly excellent in abrasion resistance, and a highly durable photoconductor can be obtained by containing them in the surface layer.
[0016]
As a method for improving the dispersion stability, a method of adding a dispersant is known. Among them, polyester resins, acrylic resins, copolymers containing such structures, monocarboxylic acids, and organic fatty acids are dispersion stable. In addition, the present inventors have found that problems such as poor charging and rise in bright part potential do not occur. By adding and dispersing these substances, a highly sensitive and highly durable photoreceptor free from image unevenness and image defects can be obtained.
[0017]
By satisfying the above configuration requirements, a method for producing an electrophotographic photosensitive member that has high durability and can stably obtain a high-quality image even after repeated use, and the photosensitive member for a long time. As a method for producing an electrophotographic photoreceptor that achieves both high durability and high image quality by providing a coating solution for a filler-containing surface layer that can be stably produced, the first group of the present invention It came to complete.
[0018]
Further, according to the second group of the present invention, a photosensitive layer is laminated directly or via an intermediate layer on a conductive substrate, and at least a binder resin and a filler, or a binder resin, a filler, and a charge transport material are formed on the photosensitive layer. In a method for producing a photoreceptor in which a surface layer containing selenium is laminated, a dispersing machine such as a ball mill, a bead mill, a sand mill, a vibration mill, or an ultrasonic wave is generally used as a method for pulverizing a filler and dispersing it in a solvent. Is the method. As the particle size of the filler is reduced, the dispersion stability is improved. Therefore, the filler is required to be crushed to a small size by applying a larger impact force or friction force.
[0019]
However, when adding a dispersing agent to the pulverizing and dispersing process, the reaggregation prevention due to the adsorption of the dispersing agent on the filler surface is the main factor for the progress of dispersion. Or situations where adsorption is hindered. Then, the extra energy added becomes heat and causes an increase in the temperature of the dispersion.
[0020]
In particular, the surface layer laminated on the photoreceptor often deteriorates in chargeability due to the addition of a dispersant, or conversely, residual charge often occurs, so the amount of dispersant added must be kept to a minimum. is there. Therefore, since the amount of the dispersing agent relative to the surface area of the filler particles is small, it is required to efficiently adsorb the dispersing agent on the filler surface. Therefore, as a result of intensive studies by the present inventors based on the relationship between the temperature increase during filler pulverization and dispersion stability, dispersion stability is suppressed by suppressing the pulverization energy so that the temperature increase during pulverization is 20 ° C. or less. It has been found that a filler-containing surface layer coating solution having excellent properties can be obtained.
[0021]
Among the dispersants, polyester resins, acrylic resins, copolymers containing these structures, monocarboxylic acids, and organic fatty acids are excellent in dispersion stability, and do not cause problems such as poor charging and increased bright part potential. We have also found out.
In particular, by using ketones and ethers as the dispersion solvent, the dissolution balance of the filler and the dispersant is improved, so that the filler can be further reduced in particle size, and the dispersion stability can be further improved.
As the filler, the inorganic pigment has higher hardness and superior wear resistance than the organic pigment. Among inorganic pigments, silica, alumina, and titanium oxide are materials that are particularly excellent in abrasion resistance, and a highly durable photoconductor can be obtained by containing them in the surface layer.
[0022]
As a dispersion method, a ball mill is the most excellent, and since there is little excessive impact and temperature rise is small, it becomes possible to create a filler-containing surface layer coating solution with better dispersion stability. When using a ball mill, if the ball diameter exceeds 10 mm, the impact force is too strong, so the dispersion stability deteriorates. If a ball smaller than 1 mm is used, the impact force is too weak to reduce the particle size. Therefore, it is possible to create a dispersion having excellent dispersion stability by using balls having a diameter of 1 mm or more and 10 mm or less.
[0023]
By including the charge transport material in the filler-containing surface layer, it is possible to suppress an increase in the bright part potential, which is considered to be caused by poor charge transportability, and thus it is possible to obtain an image free from background stains. Further, when a polymer charge transport material is used, the strength of the film is improved, so that the wear resistance can be improved.
[0024]
By satisfying the above structural requirements, a method for producing an electrophotographic photosensitive member that has high durability and can stably obtain a high-quality image even for repeated use, and those photosensitive members over a long period of time. Completed the second group of the present invention as a method for producing an electrophotographic photosensitive member that achieves both high durability and high image quality by providing a coating solution for a filler-containing surface layer that can be stably produced. I came to let you.
[0025]
Furthermore, in the third group of the present invention, a photosensitive layer is laminated directly or via an intermediate layer on a conductive substrate, and at least a binder resin and a filler, or a binder resin, a filler, and a charge transport material are placed on the photosensitive layer. In the method for producing a photoreceptor in which the surface layer to be contained is laminated, the filler dispersion state in the surface layer coating solution is greatly influenced by negative ions, particularly chlorine ions, and the dispersion of the filler increases as the chlorine ion concentration increases. There is a tendency that the particle size increases and the sedimentation property also deteriorates. The degree to which the dispersion stability deteriorates varies depending on the concentration of the filler and binder resin in the surface layer coating solution, the type of solvent, etc. No deterioration was observed, and the surface layer prepared using such a coating solution found that a good coating film having no film thickness unevenness and roughness was obtained, leading to the third group of the present invention.
[0026]
Chlorine ions may be contained in a small amount in the solvent, and when a solvent having a chlorine ion concentration exceeding 1 ppm is used, a coating solution for the surface layer having poor dispersion stability is completed. In order to prevent such a situation from occurring, it has been devised to use an ion adsorbent as a method for removing chlorine ions from a solvent in advance.
[0027]
As the ion adsorbent, activated clay, florisil, and basic alumina can be used satisfactorily because they have a high adsorption power of chlorine ions and do not elute components that affect the charging characteristics of the photoreceptor.
[0028]
As a method for improving the dispersion stability, there is a method of adding a dispersant. However, if the dispersant is contained in the surface layer, it may cause problems such as poor charging and a bright portion potential increase. In many cases, the amount is limited to the minimum amount. Similarly, when the dispersant is used in the surface layer coating liquid, the filler particle size increases as the concentration of chloride ions increases, and the sedimentation tends to deteriorate. If it is 1 ppm or less, the sedimentation property is not deteriorated.
[0029]
Among the dispersants, polyester resins, acrylic resins, copolymers containing these structures, monocarboxylic acids, and organic fatty acids are excellent in dispersion stability, and do not cause problems such as poor charging and increased bright part potential. We have also found out.
[0030]
As the filler, the inorganic pigment has higher hardness and superior wear resistance than the organic pigment. Among inorganic pigments, silica, alumina, and titanium oxide are materials that are particularly excellent in abrasion resistance, and a highly durable photoconductor can be obtained by containing them in the surface layer.
[0031]
By including the charge transport material in the filler-containing surface layer, it is possible to suppress an increase in the bright part potential, which is considered to be caused by poor charge transportability, and thus it is possible to obtain an image free from background stains. Further, when a polymer charge transport material is used, the strength of the film is improved, so that the wear resistance can be improved.
[0032]
By satisfying the above structural requirements, a method for producing an electrophotographic photosensitive member that has high durability and can stably obtain a high-quality image even for repeated use, and those photosensitive members over a long period of time. Completed the third group of the present invention as a method for producing an electrophotographic photosensitive member that achieves both high durability and high image quality by providing a coating solution for a filler-containing surface layer that can be stably produced. I came to let you.
[0033]
  That is, the above-mentioned subject is (1) "In a method for producing an electrophotographic photosensitive member comprising a laminate of at least a photosensitive layer and a surface layer containing a binder resin and a filler on a conductive support, the filler is dispersed in the solvent and the binder resin using a dispersant. The method for producing an electrophotographic photosensitive member, wherein an increase in liquid temperature is 20 ° C. or less in a pulverizing step or a pulverizing step of dispersing a filler in a solvent using a dispersant ”2) “As a dispersant used in the filler dispersion step, a polyester resin, an acrylic resin, or a copolymer containing such a structure, a monocarboxylic acid, and an organic fatty acid may be added alone or in admixture of two or more. The first feature (1)In termsManufacturing method of electrophotographic photosensitive member according to the description ", (3) “Item (1) above, wherein at least a solvent selected from ketones and ethers is used in the filler dispersion step.Or item (2)Manufacturing method of electrophotographic photosensitive member according to the above ", (4) “Item (1) to Item (1), wherein the surface layer coating liquid contains a charge transporting substance.3) Method for producing an electrophotographic photosensitive member according to any one of items ", (5) “The charge transport material contained in the surface layer coating solution is a polymer charge transport material (4The method for producing the electrophotographic photosensitive member according to the item) ”, (6) “The filler dispersed in the surface layer coating liquid is an inorganic pigment,” the items (1) to (5The method for producing an electrophotographic photosensitive member according to any one of items 1), (7) “The inorganic pigment dispersed in the coating liquid for the surface layer is one selected from silica, alumina, and titanium oxide.6The method for producing the electrophotographic photosensitive member according to the item) ”, (8) “The above-mentioned (characterized in that a ball mill is used for dispersing the filler”1The method for producing the electrophotographic photosensitive member according to the item) ”, (9) “A ball having a diameter of 1 mm or more and 10 mm or less is used as the dispersion medium.8The method for producing an electrophotographic photosensitive member according to the item) is achieved.
[0034]
  In addition, the above problem is10) "Item (1) to (9This is achieved by an electrophotographic photosensitive member produced by the production method according to any one of the items).
  In addition, the above problem is11) “An electrophotographic apparatus comprising at least a charging means, an image exposing means, a developing means, a transferring means, a cleaning means, a charge eliminating means, and an electrophotographic photosensitive member, wherein the electrophotographic photosensitive member is the above (10This is achieved by an “electrophotographic apparatus characterized by using the electrophotographic photosensitive member according to the item)”.
[0035]
As described above, the present invention can be grasped by dividing it into the invention of the first group, the invention of the second group, and the invention of the third group. According to the present invention of the first group, Filler can be dispersed, and according to the second group of the present invention, a filler-containing surface layer coating solution having excellent dispersion stability can be prepared by suppressing the temperature rise in the pulverization step to 20 ° C. or less. According to the third group of the present invention, a filler-containing surface layer coating solution having excellent dispersion stability can be prepared by regulating the chlorine ion concentration to 1 ppm or less, so that it is highly durable and stable for repeated use. It is possible to provide a photoconductor that can form a high-quality image.
[0036]
Hereinafter, the present invention will be described in detail.
Fillers used in the present invention include organic pigments such as melamine resin particles and silicone resin particles, titanium oxide, silica, tin oxide, alumina, zirconium oxide, indium oxide, silicon nitride, calcium oxide, magnesium oxide, zinc oxide, and barium sulfate. Inorganic pigments such as silica, alumina, and titanium oxide are particularly preferable.
[0037]
In addition, the above-mentioned filler whose surface has been hydrophobized is also used favorably, and is generally treated with a silane coupling agent as a hydrophobizing treatment, or treated with a fluorinated silane coupling agent, treated with a higher fatty acid, or inorganic. As the treatment, a filler surface treated with alumina, zirconia, tin oxide, or silica is known.
[0038]
Examples of the binder resin include acrylic resins, polyesters, polycarbonates, polyamides, polyurethanes, polystyrenes, epoxy resins, and the like. Particularly preferred binder resins are polycarbonates represented by the following general formulas (1) and (2).
[0039]
[Chemical 1]

[0040]
[Chemical 2]

[0041]
R_Four, R_Five, R₆, R₇Each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group or a halogen atom, or a substituted or unsubstituted aryl group. X represents an aliphatic divalent group or a cycloaliphatic divalent group, Y represents a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O-, -S- , -SO-, -SO₂-, -CO-, -CO-O-Z-O-CO- (wherein Z represents an aliphatic divalent group), or
[0042]
[Chemical 3]

(Wherein, a is an integer of 1 to 20, b is an integer of 1 to 2000, R₈, R₉Represents a substituted or unsubstituted alkyl group or aryl group. ). Where R₆And R₇, R₈And R₉May be the same or different. p and q represent compositions, 0.1 ≦ p ≦ 1, 0 ≦ q ≦ 0.9, and n represents the number of repeating units, which is an integer of 5 to 5000.
[0043]
These polycarbonates have high toughness and good film properties, and since the filler layer has a charge transport function, it is an important condition that compatibility with the charge transport material is important. Polycarbonates represented by 1) and general formula (2) are preferred.
[0044]
A charge transport material is added to the surface layer containing the filler in order to impart a charge transport function. Examples of the charge transport material to be added include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, and styryl. Anthracene, styrylpyrazoline, phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, and the like can be given. These charge transport materials can be used alone or as a mixture of two or more.
[0045]
In particular, the charge transport material represented by the following general formula (3) is preferable because of its high mobility and good compatibility with the binder resin.
[0046]
[Formula 4]

R₁Represents a hydrogen atom, a substituted or unsubstituted alkyl group or a halogen atom, or a substituted or unsubstituted aryl group. R₂, R_ThreeRepresents a substituted or unsubstituted aryl group. R₁Represents a hydrogen atom, each independently a substituted or unsubstituted alkyl group or a halogen atom. Specific examples thereof include the following, which may be the same or different.
[0047]
The alkyl group is preferably C₁~ C₁₂C in particular₁~ C₈, More preferably C₁~ C_FourThese alkyl groups are further a fluorine atom, a hydroxyl group, a cyano group, C₁~ C_FourAn alkoxy group, a phenyl group, or a halogen atom, C₁~ C_FourAlkyl group or C₁~ C_FourA phenyl group substituted with an alkoxy group may be contained.
[0048]
Specifically, methyl group, ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n-butyl group, i-butyl group, trifluoromethyl group, 2-hydroxyethyl Group, 2-cyanoethyl group, 2-ethoxyethyl group, 2-methoxyethyl group, benzyl group, 4-chlorobenzyl group, 4-methylbenzyl group, 4-methoxybenzyl group, 4-phenylbenzyl group and the like.
[0049]
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R₂, R_ThreeRepresents a substituted or unsubstituted aryl group, and specific examples thereof include the following, which may be the same or different.
[0050]
As an aromatic hydrocarbon group, a styryl group, a phenyl group, a condensed polycyclic group as a naphthyl group, a pyrenyl group, a 2-fluorenyl group, a 9,9-dimethyl-2-fluorenyl group, an azulenyl group, an anthryl group, a triphenylenyl group, Examples include a chrycenyl group, a fluorenylidenephenyl group, a 5H-dibenzo [a, d] cycloheptenylidenephenyl group, and a non-condensed polycyclic group such as a biphenylyl group and a terphenylyl group.
[0051]
Examples of the heterocyclic group include a thienyl group, a benzothienyl group, a furyl group, a benzofuranyl group, and a carbazolyl group.
[0052]
The above-mentioned aryl group may have the following groups as a ring substituent.
(1) Halogen atom, trifluoromethyl group, cyano group, nitro group.
(2) As the alkyl group, the above R₁, R₂, R_ThreeThe same thing is mentioned.
(3) As an alkoxy group, an alkyl group represents the alkyl group defined in (2). Specifically, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, s-butoxy group, i-butoxy group, 2-hydroxyethoxy group, 2-cyano Examples include ethoxy group, benzyloxy group, 4-methylbenzyloxy group, trifluoromethoxy group and the like.
(4) As an aryloxy group, a phenyl group and a naphthyl group are mentioned as an aryl group. This is C₁~ C_FourAn alkoxy group of₁~ C_FourThese alkyl groups or halogen atoms may be contained as a substituent. Specific examples include phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methylphenoxy group, 4-methoxyphenoxy group, 4-chlorophenoxy group, 6-methyl-2-naphthyloxy group and the like. It is done.
(5) Specific examples of the substituted mercapto group or aryl mercapto group include a methylthio group, an ethylthio group, a phenylthio group, and a p-methylphenylthio group.
(6) As the alkyl-substituted amino group, the alkyl group represents the alkyl group defined in (2). Specific examples include a dimethylamino group, a diethylamino group, an N-methyl-N-propylamino group, and an N, N-dibenzylamino group.
(7) Specific examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a malonyl group, and a benzoyl group.
[0053]
The content ratio of the charge transport material (D), the binder resin (R) and the filler (F) in the surface layer containing the filler is D: R: F = 10-40: 35-55: 5-40. When the amount of the charge transporting material is 10% by weight or less, the bright portion potential is considered to be increased due to the decrease in charge transporting property, and when it is 40% by weight or more, the film strength is decreased. The binder resin is used to fix the charge transport material and the filler. When the content is 35% by weight or less, the filler layer is embrittled, and when the content is 55% by weight or more, the balance between the charge transport material and the amount of the filler is obtained. This is not preferable in terms of electrical characteristics and film strength. If the amount of filler is 5% by weight or less, it is not preferable in terms of wear resistance, and if it is 40% by weight or more, image deterioration such as scumming due to film opacification occurs.
[0054]
Dispersing solvents include ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, ethers such as dioxane, 1,3-dioxolane, tetrahydrofuran, ethyl cellosolve, aromatics such as toluene and xylene, chlorobenzene, Halogens such as dichloromethane and esters such as ethyl acetate and butyl acetate are used, and they are dispersed and pulverized using a ball mill, sand mill, vibration mill or the like.
[0055]
The filler is dispersed in a volume average particle size of 0.05 to 1.5 μm, preferably 0.2 to 1.0 μm. When the volume average particle size is smaller than 0.2 μm, there is a drawback that the wear resistance is lowered. When the volume average particle size is larger than 1.0 μm, the resolution is reduced due to scattering of writing light, Protruding to damage the cleaning blade, resulting in poor cleaning.
[0056]
The film thickness of the outermost surface layer containing the filler is 0.5 to 10 μm, preferably 1 to 6 μm. As the coating method, a dipping method, a spray coating method, a ring coating method, a roll coater method, a gravure coating method, a nozzle coating method, a screen printing method, or the like is employed. When a surface layer containing a filler is provided on a charge transport layer composed of a charge transport material and a binder resin, the structure of the binder resin used in the charge transport layer and the binder resin used in the filler layer may be the same or different. I do not care.
[0057]
The electrophotographic photosensitive member of the present invention will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view showing a structural example of an electrophotographic photosensitive member used in the present invention. A single-layer photosensitive layer (2) comprising a charge generating material and a charge transporting material as main components on a conductive support (1). ) And a surface layer (3) containing a filler is provided thereon.
FIG. 2 is a cross-sectional view showing another structural example of the electrophotographic photosensitive member of the present invention, in which a charge generation layer (4) containing a charge generation material as a main component and a charge transport material on a conductive support (1). And a surface layer (3) containing a filler is provided thereon.
[0058]
The surface layer containing the filler is provided on the following layer.
As a conductive support, a volume resistance of 10^TenConductives with a conductivity of Ω or less, for example, metals such as aluminum, nickel, chromium, nichrome, copper, silver, gold, platinum, iron, and oxides such as tin oxide and indium oxide are deposited or sputtered into a film or cylinder Plastic, paper, etc., or a plate of aluminum, aluminum alloy, nickel, stainless steel, etc. I. , I. I. , Pipes that have been surface-treated by cutting, superfinishing, polishing, etc. after being made into bare pipes by methods such as extrusion and drawing can be used.
[0059]
The photosensitive layer in the present invention may be a single layer type or a multilayer type, but here, for convenience of explanation, a multilayer type will be described first.
First, the charge generation layer will be described. The charge generation layer is a layer mainly composed of a charge generation material, and a binder resin may be used as necessary. As the charge generation material, inorganic materials and organic materials can be used.
[0060]
Inorganic materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compounds, and amorphous silicon. In amorphous silicon, dangling bonds that are terminated with hydrogen atoms or halogen atoms, or those that are doped with boron atoms, phosphorus atoms, or the like are preferably used.
[0061]
On the other hand, a known material can be used as the organic material. For example, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azulenium salt pigments, squaric acid methine pigments, azo pigments having a carbazole skeleton, azo pigments having a triphenylamine skeleton, azo pigments having a diphenylamine skeleton, dibenzothiophene skeleton Azo pigments having fluorenone skeleton, azo pigments having oxadiazole skeleton, azo pigments having bis-stilbene skeleton, azo pigments having distyryl oxadiazole skeleton, azo pigments having distyrylcarbazole skeleton, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, Jigoido based pigments, and bisbenzimidazole pigments. These charge generation materials can be used alone or as a mixture of two or more.
[0062]
Binder resins used as necessary for the charge generation layer include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinyl. Carbazole, polyacrylamide and the like are used. These binder resins can be used alone or as a mixture of two or more. Furthermore, you may add a charge transport material as needed.
[0063]
Examples of the charge transport material include the electron donating materials shown below and are used favorably. For example, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline , Phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, and the like. These charge transport materials can be used alone or as a mixture of two or more.
[0064]
Methods for forming the charge generation layer include a vacuum thin film preparation method and a casting method from a solution dispersion system.
As the former method, a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used, and the above-described inorganic materials and organic materials can be satisfactorily formed.
[0065]
In addition, in order to provide the charge generation layer by the casting method described later, the inorganic or organic charge generation material described above is used together with a binder resin, if necessary, with a solvent such as tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, butanone, ball mill, atom It can be formed by dispersing with a lighter, sand mill or the like and applying the solution after diluting the dispersion appropriately. The coating can be performed using a dip coating method, a spray coating method, a bead coating method, or the like.
The thickness of the charge generation layer provided as described above is suitably about 0.01 to 5 μm, preferably 0.05 to 2 μm.
[0066]
Next, the charge transport layer will be described.
The charge transport layer can be used as a charge transport layer by dissolving and coating both the charge transport material and the binder resin. Binder resin has good film properties such as polycarbonate (bisphenol A type, bisphenol Z type, bisphenol C type or copolymers thereof), polyarylate, polysulfone, polyester, methacrylic resin, polystyrene, vinyl acetate, epoxy resin, phenoxy resin Etc. are used. These binders can be used alone or as a mixture of two or more.
[0067]
The charge transport materials used in the charge transport layer include oxazole derivatives, oxadiazole derivatives (described in JP-A Nos. 52-139065 and 52-139066), imidazole derivatives, triphenylamine derivatives (Japanese Patent Application No. 1). -77839), benzidine derivatives (described in Japanese Patent Publication No. 58-32372), α-phenylstilbene derivatives (described in Japanese Patent Application Laid-Open No. 57-73075), hydrazone derivatives (Japanese Patent Application Laid-Open No. 55-154955). No. 55-156654, No. 55-52063, No. 56-81850, etc.), triphenylmethane derivatives (described in Japanese Patent Publication No. 51-10983), anthracene derivatives (Japanese Unexamined Patent Publication No. 51-94829). Styryl derivatives (Japanese Patent Laid-Open No. 56-29245, 58-1). Described in 8043 JP), described in JP-carbazole derivatives (JP-58-58552), or the like can be used pyrene derivatives (described in Japanese Patent Application No. 2-94812 specification).
[0068]
In addition, a polymer charge transport material having a function as a charge transport material and a function of a binder resin is also preferably used for the charge transport layer. The charge transport layer composed of these polymer charge transport materials is excellent in wear resistance. As the polymer charge transport material, known materials can be used, and in particular, a polycarbonate containing a triarylamine structure in the main chain and / or side chain is preferably used. Among these, polymer charge transport materials represented by the following formulas (I) to (X) are favorably used, and these are exemplified below and specific examples are shown.
[0069]
[Chemical formula 5]

Where R₁, R₂, R_ThreeEach independently represents a substituted or unsubstituted alkyl group or a halogen atom, R_FourIs a hydrogen atom or a substituted or unsubstituted alkyl group, R_Five, R₆Is a substituted or unsubstituted aryl group, o, p and q are each independently an integer of 0 to 4, k and j are compositions, 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9, n Represents the number of repeating units and is an integer of 5 to 5000. X represents an aliphatic divalent group, a cycloaliphatic divalent group, or a divalent group represented by the following general formula.
[0070]
[Chemical 6]

Where R₁₀₁, R₁₀₂Each independently represents a substituted or unsubstituted alkyl group, aryl group or halogen atom. l and m are integers of 0 to 4, Y is a single bond, a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, -O-, -S-, -SO-, -SO.₂-, -CO-, -CO-O-Z-O-CO- (wherein Z represents an aliphatic divalent group) or
[0071]
[Chemical 7]

(Wherein, a is an integer of 1 to 20, b is an integer of 1 to 2000, R₁₀₃, R₁₀₄Represents a substituted or unsubstituted alkyl group or aryl group. ). Where R₁₀₁And R₁₀₂, R₁₀₃And R₁₀₄May be the same or different.
[0072]
[Chemical 8]

Where R₇, R₈Is a substituted or unsubstituted aryl group, Ar₁, Ar₂, Ar_ThreeRepresent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0073]
[Chemical 9]

Where R₉, R_TenIs a substituted or unsubstituted aryl group, Ar_Four, Ar_Five, Ar₆Represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0074]
[Chemical Formula 10]

Where R₁₁, R₁₂Is a substituted or unsubstituted aryl group, Ar₇, Ar₈, Ar₉Are the same or different arylene groups, and p represents an integer of 1 to 5. X, k, j and n are the same as in the case of formula (I).
[0075]
Embedded image

Where R₁₃, R₁₄Is a substituted or unsubstituted aryl group, Ar_Ten, Ar₁₁, Ar₁₂Are the same or different arylene groups, X₁, X₂Represents a substituted or unsubstituted ethylene group or a substituted or unsubstituted vinylene group. X, k, j and n are the same as in the case of formula (I).
[0076]
Embedded image

Where R₁₅, R₁₆, R₁₇, R₁₈Is a substituted or unsubstituted aryl group, Ar₁₃, Ar₁₄, Ar₁₅, Ar₁₆Are the same or different arylene groups, Y₁, Y₂, Y_ThreeRepresents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group, which may be the same or different. X, k, j and n are the same as in the case of formula (I).
[0077]
Embedded image

Where R₁₉, R₂₀Represents a hydrogen atom, a substituted or unsubstituted aryl group, and R₁₉And R₂₀May form a ring. Ar₁₇, Ar₁₈, Ar₁₉Represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0078]
Embedded image

Where R_{twenty one}Is a substituted or unsubstituted aryl group, Ar₂₀, Ar_{twenty one}, Ar_{twenty two}, Ar_{twenty three}Represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0079]
Embedded image

Where R_{twenty two}, R_{twenty three}, R_{twenty four}, R_{twenty five}Is a substituted or unsubstituted aryl group, Ar_{twenty four}, Ar_{twenty five}, Ar₂₆, Ar₂₇, Ar₂₈Represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0080]
Embedded image

Where R₂₆, R₂₇Is a substituted or unsubstituted aryl group, Ar₂₉, Ar₃₀, Ar₃₁Represent the same or different arylene groups. X, k, j and n are the same as in the case of formula (I).
[0081]
The thickness of the charge transport layer is suitably about 5 to 100 μm, preferably about 10 to 40 μm.
In the present invention, a plasticizer or a leveling agent may be added to the charge transport layer. As the plasticizer, those generally used as a plasticizer for resins such as dibutyl phthalate and dioctyl phthalate can be used as they are. It is.
[0082]
Next, the case where the photosensitive layer has a single layer structure will be described.
In the case of providing a single-layer photosensitive layer by a casting method or the like, a function separation type composed of a charge generation material, a charge transport material, and a binder resin is often used. That is, the above-described materials can be used for the charge generation material and the charge transport material.
Moreover, a plasticizer and a leveling agent can also be added as needed. Furthermore, as a binder resin that can be used as needed, the binder resin mentioned above in the charge transport layer may be used as it is, or the binder resin mentioned in the charge generation layer may be mixed and used. The film thickness of the single-layer photoconductor is suitably about 5 to 100 μm, and preferably about 10 to 40 μm.
[0083]
In the electrophotographic photoreceptor used in the present invention, an undercoat layer can be provided between a conductive support and a photosensitive layer (a charge generation layer in the case of a laminated type). The undercoat layer is provided for the purpose of improving adhesiveness, preventing moire and the like, improving the coatability of the upper layer, and reducing the residual potential. In general, the undercoat layer is mainly composed of a resin. However, considering that the photosensitive layer is applied with a solvent on these resins, the resin may be a resin having a high resistance to a general organic solvent. desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, alkyd-melamine resin, and epoxy resin. And a curable resin that forms a three-dimensional network structure. Further, fine powders such as metal oxides exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like, or metal sulfides and metal nitrides may be added. These undercoat layers can be formed using an appropriate solvent and coating method as in the photosensitive layer described above.
[0084]
Furthermore, a metal oxide layer formed by, for example, a sol-gel method using a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like is also useful as the undercoat layer of the present invention.
In addition to this, the undercoat layer of the present invention includes Al.₂O_ThreePrepared by anodic oxidation, organic matter such as polyparaxylylene (parylene), SiO, SnO₂TiO₂, ITO, CeO₂A material provided with an inorganic material such as a vacuum thin film can also be used favorably. The thickness of the undercoat layer is suitably from 0 to 8 μm.
[0085]
In the present invention, an antioxidant may be added for the purpose of preventing the decrease in sensitivity and the increase in residual potential, in order to improve the environmental resistance. The antioxidant may be added to any layer containing an organic substance, but good results are obtained when it is added to a layer containing a charge transport material.
[0086]
The following are mentioned as antioxidant which can be used for this invention.
Monophenolic compounds
2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl-4 -Hydroxyphenyl) propionate and the like.
[0087]
Bisphenol compounds
2,2′-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2′-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4′-thiobis- ( 3-methyl-6-tert-butylphenol), 4,4′-butylidenebis- (3-methyl-6-tert-butylphenol) and the like.
[0088]
High molecular phenolic compounds
1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t- Butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4 ′ -Hydroxy-3'-t-butylphenyl) butyric acid] glycol ester, tocopherols and the like.
[0089]
Paraphenylenediamines
N-phenyl-N'-isopropyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylenediamine, N, N'- Di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine and the like.
[0090]
Hydroquinones
2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2- (2-octadecenyl) ) -5-methylhydroquinone and the like.
[0091]
Organic sulfur compounds
Dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate, and the like.
[0092]
Organophosphorus compounds
Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine, and the like.
[0093]
These compounds are known as antioxidants such as rubbers, plastics and fats and oils, and commercially available products can be easily obtained. The addition amount of the antioxidant in the present invention is 0.1 to 100 parts by weight, preferably 2 to 30 parts by weight with respect to 100 parts by weight of the charge transport material.
[0094]
Next, the present invention provides an electrophotographic method characterized in that charging, image exposure, and transfer are performed using the above electrophotographic photosensitive member. The present invention also provides an electrophotographic apparatus having the above-described electrophotographic photosensitive member and provided with a charging unit, an image exposure unit, and a transfer unit. Further, the electrophotographic photosensitive member and at least one means selected from charging means, image exposure means, developing means, transfer means and cleaning means are integrally formed so as to be detachable from the main body of the electrophotographic apparatus. A process cartridge for an electrophotographic apparatus is provided.
The electrophotographic method, electrophotographic apparatus, and process cartridge for an electrophotographic apparatus will be described with reference to the drawings.
[0095]
FIG. 3 is a schematic view of the electrophotographic apparatus and the process cartridge for the electrophotographic apparatus of the present invention. Although the photoconductor (11) has a drum shape, it may be a sheet or an endless belt. A charging charger (13), a pre-transfer charger (17), a transfer charger (20), a separation charger (21), and a pre-cleaning charger (23) include a corotron, a scorotron, a solid state charger, and charging. Known means such as a roller is used.
As the transfer means, the above charger can be generally used. However, as shown in the figure, a combination of a transfer charger and a separation charger is effective.
[0096]
An LD or LED is used for the image exposure unit (15). In addition, as a light source such as a static elimination lamp (12), all luminescent materials such as a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, an LED, an LD, and an electroluminescence element (EL) can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range. At this time, the beam system of the image exposure unit and the writing light source is preferably 10 to 30 μm in order to achieve a high resolution equivalent to 1200 to 2400 dpi. Such a light source or the like irradiates the photoreceptor with light by providing a transfer process, a static elimination process, a cleaning process, or a pre-exposure process in combination with light irradiation in addition to the process shown in FIG.
[0097]
The toner developed on the photoconductor (11) by the developing unit (16) is transferred to the transfer paper (19), but not all is transferred, and the toner remaining on the photoconductor (11) is also transferred. Arise. Such toner is removed from the photoreceptor by the fur brush (24) and the blade (25). Cleaning may be performed only with a cleaning brush, and a known brush such as a fur brush or a mag fur brush is used as the cleaning brush.
[0098]
When the electrophotographic photosensitive member is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. If this is developed with toner of negative (positive) polarity (detection fine particles), a positive image can be obtained, and if developed with toner of positive (negative) polarity, a negative image can be obtained. A known method is applied to the developing unit, and a known method is also used for the charge eliminating unit.
[0099]
FIG. 4 is a schematic view of another electrophotographic apparatus of the present invention. The photoconductor (31) is a photoconductor of the present invention, which is driven by driving rollers (32a) and (32b), charged by a charger (33), image exposure by a light source (34), development (not shown), Transfer using the charger (35), exposure before cleaning by the light source (36), cleaning by the brush (37), and charge removal by the light source (38) are repeated. In FIG. 5, the photoconductor (21) (of course, the support is translucent in this case) is irradiated with pre-cleaning exposure light from the support side.
[0100]
The electrophotographic method and the electrophotographic apparatus illustrated above exemplify the embodiments in the present invention, and other embodiments are possible. For example, in FIG. 4, the pre-cleaning exposure is performed from the support side, but this may be performed from the photosensitive layer side, or image exposure and neutralization light irradiation may be performed from the support side.
In addition, the light irradiation process is illustrated as image exposure, pre-cleaning exposure, and static elimination exposure. In addition, a pre-transfer exposure, pre-exposure of image exposure, and other known light irradiation processes are provided to light the photosensitive member. Irradiation can also be performed.
[0101]
The image forming means performed in this way may be fixedly incorporated in a copying apparatus, a facsimile machine, or a printer, but may be incorporated in these apparatuses in the form of a process cartridge. A process cartridge is a device and a part that includes a photosensitive member and includes a charging unit, an exposure unit, a developing unit, a transfer unit, a cleaning unit, and a charge eliminating unit. There are many examples of the shape of the process cartridge. Here, one example is shown in FIG. This process cartridge comprises the electrophotographic photosensitive member (26) of the present invention, a charging charger (27), a cleaning brush (28), an image exposure unit (29), and a developing roller (30).
[0102]
【Example】
  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not restrict | limited by an Example. All parts are parts by weight.
[About the first group of the present invention]
Reference example1
  By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on a φ30 mm aluminum cylinder in sequence, an undercoat layer of 3.5 μm, 0 A 2 μm charge generation layer and a 25 μm charge transport layer were formed. On top of that, xylene and the following organic filler are dispersed for 12 hours using a ball mill containing alumina balls, and the following binder resin is dissolved in toluene and added to the above dispersion and mixed to obtain a surface layer coating solution. 1 was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Table 1 shows the volume average particle size of the surface layer coating solution, the sedimentation test results, the initial image of the photoreceptor provided with the surface layer, the image evaluation results after running 10,000 sheets, and the wear loss of the surface layer. .
[0103]
[Coating liquid for undercoat layer]
Alkyd resin 6 parts
(Beccosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin 4 parts
(Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
Titanium oxide (CREL, manufactured by Ishihara Sangyo) 40 parts
200 parts of methyl ethyl ketone
[0104]
[Coating liquid for charge generation layer]
Oxotitanium phthalocyanine pigment 2 parts
Polyvinyl butyral (UCC: XYHL) 0.2 part
50 parts of tetrahydrofuran
[0105]
[Coating liquid for charge transport layer]
Polycarbonate resin
(Z Polica, manufactured by Teijin Chemicals Ltd., Mv50,000) 10 parts
100 parts of dichloromethane
1% silicone oil
(KF50, manufactured by Shin-Etsu Silicone) 1 part of dichloromethane solution
3 parts of charge transport material represented by the following structural formula (XI)
[0106]
Embedded image

[0107]
[Coating liquid for surface layer 1]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
60 parts of xylene
180 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0108]
Reference example2
  Reference exampleIn the same manner as in No. 1, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and then cyclohexanone and the following organic filler are dispersed for 12 hours using a ball mill containing alumina balls, and the following binder resin is dissolved in tetrahydrofuran there. And it added to the said dispersion liquid and mixed and the coating liquid 2 for surface layers was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0109]
[Coating liquid for surface layer 2]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0110]
Reference example3
  Reference exampleIn the same manner as in No. 1, an undercoat layer, a charge generation layer, and a charge transport layer were provided, and then cyclopentanone and the following organic filler were dispersed for 12 hours using a ball mill containing alumina balls. The transport material (XI) formula was dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 3. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0111]
[Coating liquid 3 for surface layer]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
60 parts of cyclopentanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XI)
[0112]
Reference example4
  Reference exampleIn the same manner as in No. 1, an undercoat layer, a charge generation layer, and a charge transport layer were provided, and then 60 parts of tetrahydrofuran and the following organic filler were dispersed for 12 hours using a ball mill containing alumina balls, in which structural formula (XII) The polymer charge transport material was dissolved in 120 parts of tetrahydrofuran and 60 parts of xylene, and added to and mixed with the above dispersion to prepare a surface layer coating solution 4. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0113]
[Coating fluid for surface layer 4]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
180 parts of tetrahydrofuran
60 parts of xylene
8 parts of polymer charge transport material of the following structural formula (XII)
[0114]
Embedded image

[0115]
Reference example5
  Reference exampleIn the same manner as in No. 1, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and then cyclohexanone and the following inorganic pigment are dispersed for 12 hours using a ball mill containing alumina balls. (XI) was dissolved in tetrahydrofuran, added to the dispersion and mixed to prepare a surface layer coating solution 5. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0116]
[Surface layer coating solution 5]
Zinc oxide (Sazex 4000, manufactured by Sakai Chemical) 2 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XI)
[0117]
Reference example6
  Reference exampleIn the same manner as in No. 1, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and then cyclopentanone and the following silica are dispersed for 12 hours using a ball mill containing alumina balls, and the following binder resin and charge transport are provided there. The substance (XI) is dissolved in 1,3-dioxolane, added to the above dispersion, and mixed to prepare a surface layer coating solution 6, which is then applied by spraying to form a surface layer of about 3.0 μm. After drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0118]
[Surface layer coating solution 6]
Silica (KMPX-100, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts
60 parts of cyclopentanone
180 parts of 1,3-dioxolane
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XI)
[0119]
Reference example7
  Reference example1 is provided with an undercoat layer, a charge generation layer, and a charge transport layer, and cyclohexanone, the following alumina and the following polycarboxylic acid are dispersed for 12 hours using a ball mill containing alumina balls, and the following binder resin is dispersed therein. And the charge transport material (XI) were dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 7. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer Table 1 shows.
[0120]
[Surface layer coating solution 7]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Oleic acid 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XI)
[0121]
[Table 1]

[0122]
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day, all dispersed particles settled
[0123]
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the amount of wear (thickness difference before and after 10,000 sheets) were measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0124]
referenceComparative Example 1
  Reference example1 is provided with an undercoat layer, a charge generation layer, and a charge transport layer.Reference exampleOrganic pigments similar to 1, xylene, andReference exampleDisperse by adding the same binder resin and toluene as in No. 1, and apply the surface layer coating liquid (threeA ratio 1) was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer It shows in Table 2.
[0125]
referenceComparative Example 2
  Reference example1 is provided with an undercoat layer, a charge generation layer, and a charge transport layer.Reference exampleThe same inorganic pigment and cyclohexanone as 5 andReference exampleDisperse by adding the same binder resin, charge transporting substance and tetrahydrofuran as in No. 5, and apply the surface layer coating liquid (threeA ratio 2) was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Reference exampleAs with 1, the volume average particle size of the coating solution for the surface layer, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer It shows in Table 2.
[0126]
referenceComparative Example 3
  Reference example1 is provided with an undercoat layer, a charge generation layer, and a charge transport layer.Reference exampleAlumina, polycarboxylic acid, cyclohexanone similar to 7 andReference exampleThe same binder resin as in No. 7, a charge transport material and 1,3-dioxolane are added to disperse, and the surface layer coating liquid (threeA ratio 3) was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Reference exampleThe volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, It shows in Table 2.
[0127]
referenceComparative Example 4
  Reference exampleAs in Example 1, an undercoat layer, a charge generation layer, and a charge transport layer were provided, and an electrophotographic photoreceptor having no surface layer was obtained.
  Reference exampleTable 2 shows the initial image of the photoreceptor, the image evaluation results after running 10,000 sheets, and the wear loss of the surface layer (charge transport layer) as in the case of 1.
[0128]
[Table 2]

[0129]
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day and all dispersed particles settled… ×
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the wear amount (thickness difference before and after 10,000 sheets are passed) are measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0130]
[About the second group of the present invention]
Example1
  By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on a φ30 mm aluminum cylinder in sequence, an undercoat layer of 3.5 μm, 0 A 2 μm charge generation layer and a 25 μm charge transport layer were formed.
  On top of that, xylene, the following organic filler, and a dispersant (methacryloxy-modified silicone) were pulverized for 2 hours with a paint shaker using a glass container containing alumina balls of φ0.2 mm and dispersed. The liquid temperature before pulverization was 20 ° C., the liquid temperature after pulverization was 35 ° C., and the temperature increased by 15 ° C. during the pulverization process. Then, the following binder resin was dissolved in toluene, added to the dispersion, and mixed to prepare a surface layer coating solution 8. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Table 3 shows the volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer. .
[0131]
[Coating liquid for undercoat layer]
Alkyd resin 6 parts
(Beccosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin 4 parts
(Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
Titanium oxide (CREL, manufactured by Ishihara Sangyo) 40 parts
200 parts of methyl ethyl ketone
[0132]
[Coating liquid for charge generation layer]
Oxotitanium phthalocyanine pigment 2 parts
Polyvinyl butyral (UCC: XYHL) 0.2 part
50 parts of tetrahydrofuran
[0133]
[Coating liquid for charge transport layer]
Polycarbonate resin
(Z Polica, manufactured by Teijin Chemicals Ltd., Mv50,000) 10 parts
100 parts of dichloromethane
1% silicone oil
(KF50, manufactured by Shin-Etsu Silicone) 1 part of dichloromethane solution
3 parts of charge transport material represented by the following structural formula (XIII)
[0134]
Embedded image

[0135]
[Surface layer coating solution 8]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
Methacryloxy modified silicone
(Silerplane FM0725, manufactured by Chisso Corporation) 0.1 part
60 parts of xylene
180 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0136]
Example2
  Example1In a paint shaker using a glass container in which an undercoat layer, a charge generation layer, and a charge transport layer are provided and xylene, the following organic filler and a dispersant (polyester resin) are placed in an alumina ball having a diameter of 0.2 mm. Dispersed by grinding for 2 hours. The liquid temperature before pulverization was 25 ° C., the liquid temperature after pulverization was 38 ° C., and the temperature increased by 13 ° C. during the pulverization process. Then, the following binder resin was dissolved in toluene, added to the dispersion, and mixed to prepare a surface layer coating solution 9. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0137]
[Coating liquid for surface layer 9]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
Polyester resin 0.05 parts
60 parts of xylene
180 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0138]
Example3
  Example1In a paint shaker using a glass container in which an undercoat layer, a charge generation layer, and a charge transport layer are provided, and cyclohexanone, the following organic filler, and a dispersant (polyester resin) are filled with φ0.2 mm alumina balls. Dispersed by grinding for 2 hours. The liquid temperature before pulverization was 20 ° C., the liquid temperature after pulverization was 33 ° C., and the temperature increased by 13 ° C. during the pulverization process. Then, the following binder resin was dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 10. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0139]
[Coating liquid 10 for surface layer]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0140]
Example4
  Example1In the same way as above, paint with a glass container in which an undercoat layer, a charge generation layer, and a charge transport layer are provided and cyclopentanone, the following inorganic pigment, and a dispersant (polyester resin) are placed in a 0.2 mm alumina ball. The mixture was pulverized with a shaker for 2 hours and dispersed. The liquid temperature before pulverization was 20 ° C., the liquid temperature after pulverization was 35 ° C., and the temperature increased by 15 ° C. during the pulverization process. Then, the following binder resin was dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 11. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0141]
[Coating liquid 11 for surface layer]
Zinc oxide (Sazex 4000, manufactured by Sakai Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclopentanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0142]
Example5
  Example1In a paint shaker using a glass container in which an undercoat layer, a charge generation layer, and a charge transport layer are provided, and cyclopentanone, silica, and a dispersing agent (oleic acid) are placed in a 0.2 mm alumina ball. Dispersed by grinding for 2 hours. The liquid temperature before pulverization was 20 ° C., the liquid temperature after pulverization was 34 ° C., and the temperature increased by 14 ° C. during the pulverization process. Then, the following binder resin was dissolved in 1,3-dioxolane, added to the dispersion, and mixed to prepare a surface layer coating solution 12. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0143]
[Coating liquid 12 for surface layer]
Silica (KMPX-100, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts
Oleic acid 0.05 parts
60 parts of cyclopentanone
180 parts of 1,3-dioxolane
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0144]
Example6
  Example1In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer were provided, and cyclohexanone, the following alumina, and a dispersant (polyester resin) were pulverized and dispersed for 12 hours using a ball mill containing alumina balls with a diameter of 20 mm. . The liquid temperature before pulverization was 16 ° C., the liquid temperature after pulverization was 22 ° C., and the temperature increased by 6 ° C. during the pulverization process. Thereupon, it was dissolved in the following binder resin and tetrahydrofuran, and added to and mixed with the above dispersion to prepare a surface layer coating solution 13. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0145]
[Surface layer coating solution 13]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0146]
Example7
  Example1In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer were provided, and cyclohexanone and the following alumina dispersant (polyester resin) were pulverized and dispersed for 12 hours using a ball mill containing φ5 mm alumina balls. The liquid temperature before pulverization was 25 ° C., the liquid temperature after pulverization was 28 ° C., and the temperature increased by 3 ° C. during the pulverization process. Then, the following binder resin was dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 14-1.
  Next, 3 parts of a charge transport material represented by the following binder resin and formula (XIII) were dissolved in tetrahydrofuran, and added to and mixed with the dispersion to prepare a surface layer coating solution 14-2.
  Further, 8 parts of the polymer charge transporting material represented by the formula (XIV) was dissolved in tetrahydrofuran, added to the dispersion, and mixed to prepare a surface layer coating solution 14-3.
  These liquids were applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 3 shows.
[0147]
[Coating liquid for surface layer 14-1]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0148]
[Coating liquid for surface layer 14-2]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XIII)
[0149]
[Coating liquid for surface layer 14-3]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
180 parts of tetrahydrofuran
8 parts of charge transport material represented by the following structural formula (XIV)
[0150]
Embedded image

[0151]
[Table 3]

[0152]
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day, all dispersed particles settled
[0153]
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the amount of wear (thickness difference before and after 10,000 sheets) were measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0154]
Comparative example1
  Example1In the same manner as in Example 1, an undercoat layer, a charge generation layer,1The same xylene, organic filler and dispersing agent as those described above were pulverized with a paint shaker for 3 hours using a glass container containing alumina balls with a diameter of 0.2 mm. The liquid temperature before pulverization was 20 ° C., the liquid temperature after pulverization was 50 ° C., and the temperature increased by 30 ° C. during the pulverization process. Examples there1Dissolve the same binder resin in toluene, add to the above dispersion, mix and apply the surface layer coating solution (ratio1)created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 4 shows.
[0155]
Comparative example2
  Example4In the same manner as in Example 1, an undercoat layer, a charge generation layer,4The same cyclopentanone, inorganic pigment, and dispersant as above were pulverized and dispersed for 1 hour while cooling with water at 16 ° C. using a bead mill containing φ 0.2 mm alumina balls. The liquid temperature before pulverization was 16 ° C., the liquid temperature after pulverization was 38 ° C., and the temperature increased by 22 ° C. during the pulverization process. Examples there4Dissolve the same binder resin in tetrahydrofuran, add to the above dispersion, and mix to prepare the surface layer coating solution (ratio2)created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 4 shows.
[0156]
Comparative example3
  Example7In the same manner as in Example 1, an undercoat layer, a charge generation layer,7The same cyclohexanone, alumina, and dispersant as described above were placed in a glass Erlenmeyer flask and dispersed by pulverizing for 2 hours while flowing tap water using an ultrasonic disperser. The liquid temperature before pulverization was 25 ° C., the liquid temperature after pulverization was 62 ° C., and the temperature increased by 38 ° C. during the pulverization process. Examples there7The same binder resin and 3 parts of the charge transport material represented by the formula (XIII) are dissolved in tetrahydrofuran, added to the dispersion, and mixed to obtain a surface layer coating solution (ratio).3)created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Example1The volume average particle size of the surface layer coating solution, the sedimentation test result, the initial image of the photoreceptor provided with the surface layer, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer are shown. 4 shows.
[0157]
Comparative example4
  Example1In the same way as the electrophotographic photosensitive member provided with an undercoat layer, a charge generation layer, and a charge transport layer, and no surface layer is laminated (ratio4)
  Example1Table 4 shows the initial image of the photoreceptor, the image evaluation result after running 10,000 sheets, and the wear loss of the surface layer (charge transport layer).
[0158]
[Table 4]

[0159]
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day and all dispersed particles settled… ×
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the wear amount (thickness difference before and after 10,000 sheets are passed) are measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0160]
[About the third group of the present invention]
Reference Example 8
  By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on a φ30 mm aluminum cylinder in sequence, an undercoat layer of 3.5 μm, 0 A 2 μm charge generation layer and a 25 μm charge transport layer were formed.
On top of that, the following organic filler and xylene were dispersed in a ball mill for 12 hours using a glass container containing φ2 mm alumina balls. Next, the following binder resin is dissolved in toluene, added to the dispersion, and mixed to form a surface layer coating solution.15It was created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0161]
[Coating liquid for undercoat layer]
Alkyd resin 6 parts
(Beccosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin 4 parts
(Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
Titanium oxide (CREL, manufactured by Ishihara Sangyo) 40 parts
200 parts of methyl ethyl ketone
[0162]
[Coating liquid for charge generation layer]
Oxotitanium phthalocyanine pigment 2 parts
Polyvinyl butyral (UCC: XYHL) 0.2 part
50 parts of tetrahydrofuran
[0163]
[Coating liquid for charge transport layer]
Polycarbonate resin
(Z Polica, manufactured by Teijin Chemicals Ltd., Mv50,000) 10 parts
100 parts of dichloromethane
1% silicone oil
(KF50, manufactured by Shin-Etsu Silicone) 1 part of dichloromethane solution
3 parts of charge transport material represented by the following structural formula (XV)
[0164]
Embedded image

[0165]
[Surface layer coating solution 15]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
100 parts of xylene
100 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0166]
Reference Example 9
  In 100 parts of toluene, 0.0005 part of zinc chloride was dissolved to obtain toluene containing 2 ppm or more of chlorine ions. After adding 20 parts of silica gel to this toluene and stirring for 1 hour, 10 μm Teflon(Registered trademark)Toluene that had been subjected to ion removal treatment was obtained by filtration using a filter made by the method.
  next,Reference Example 8Provide an undercoat layer, charge generation layer, and charge transport layer similar toReference Example 8The same organic filler and xyleneReference Example 8Was dispersed in the same manner. further,Reference Example 8The surface layer coating solution 16 was prepared by dissolving the same binder resin in toluene as above and adding to the filler dispersion and mixing. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0167]
Reference Example 10
  Reference Example 9In the same manner as above, toluene containing 2 ppm or more of chlorine ions was prepared. To this toluene,Reference exampleUsing Florisil (manufactured by Kanto Chemical) instead of silica gel of 2,Reference Example 9Toluene that had been subjected to ion removal treatment in the same manner as above was obtained.
  next,Reference Example 9A surface layer coating solution 17 was prepared by the same method as above, and this solution was applied by spraying to provide a surface layer of about 3.0 μm. After drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0168]
Reference Example 11
  Reference Example 8In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and the following organic filler, dispersant (methacryloxy-modified silicone) and xylene are added.Reference Example 8Was dispersed in the same manner. Next, the following binder resin was dissolved in toluene, added to the dispersion, and mixed to prepare a surface layer coating solution 18. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0169]
[Surface layer coating solution 18]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
Methacryloxy modified silicone
(Silerplane FM0725, manufactured by Chisso Corporation) 0.05 parts
100 parts of xylene
100 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0170]
Reference Example 12
  Reference Example 8In the same manner as in Example 1, except that an undercoat layer, a charge generation layer, and a charge transport layer are provided, and the dispersant is changed from a methacryloxy-modified silicone to a polyester resin.Reference Example 11A surface layer coating solution 19 was prepared in the same manner as described above. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0171]
[Coating liquid 19 for surface layer]
Spherical melamine (Eposter S, made by Nippon Shokubai) 2 parts
Polyester resin 0.05 parts
100 parts of xylene
100 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0172]
Reference Example 13
  Reference Example 8In addition to providing an undercoat layer, a charge generation layer, a charge transport layer, and replacing the organic filler with an inorganic pigmentReference Example 12A surface layer coating solution 20 was prepared in the same manner as described above. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0173]
[Coating liquid 20 for surface layer]
Zinc oxide (Sazex 4000, manufactured by Sakai Chemical) 2 parts
Polyester resin 0.05 parts
100 parts of xylene
100 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0174]
Reference Example 14
  Reference Example 8In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and the following alumina, dispersant (polyester resin), and cyclohexanone are added.Reference Example 8Distributed in the same way. Next, the following binder resin was dissolved in toluene, added to the dispersion, and mixed to prepare a surface layer coating solution 21. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0175]
[Surface layer coating solution 21]
Titanium oxide (CR-EL, manufactured by Ishihara Sangyo) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
140 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
[0176]
Reference Example 15
  Reference Example 8In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and the following alumina, dispersant (polyester resin), and cyclohexanone are added.Reference Example 8Distributed in the same way. Next, the binder resin and the charge transport material represented by the structural formula (XVI) below were dissolved in toluene, added to the dispersion, and mixed to prepare a surface layer coating solution 22. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0177]
[Surface layer coating solution 22]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
140 parts of toluene
Polycarbonate resin
(Z Polyca, Teijin Chemicals, Mv50,000) 5 parts
3 parts of charge transport material represented by structural formula (XVI)
[0178]
Reference Example 16
  Reference Example 8In the same manner as above, an undercoat layer, a charge generation layer, and a charge transport layer are provided, and the following alumina, dispersant (polyester resin), and cyclohexanone are added.Reference Example 8Distributed in the same way. Next, the surface layer coating solution 23 was prepared by dissolving the polymer charge transporting material represented by the structural formula (XVI) in toluene and adding the mixture to the dispersion, followed by mixing. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photoreceptor of the present invention was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 5 shows.
[0179]
[Surface layer coating solution 23]
Alumina (AKP-50, manufactured by Sumitomo Chemical) 2 parts
Polyester resin 0.05 parts
60 parts of cyclohexanone
140 parts of toluene
8 parts of a polymer charge transport material represented by the following structural formula (XVI)
[0180]
Embedded image

[0181]
[Table 5]

[0182]
Chlorine ion concentration was determined by semi-quantitative measurement of the separated water using an ion chromatograph by adding an equal amount of ion-exchanged water to the coating solution, shaking and leaving it to stand.
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day, all dispersed particles settled
[0183]
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the amount of wear (thickness difference before and after 10,000 sheets) were measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0184]
referenceComparative example5
  Reference Example 9In the same manner as above, toluene containing 2 ppm or more of chlorine ions was prepared. next,Reference Example 8As well as providing an undercoat layer, a charge generation layer, and a charge transport layer,Reference Example 8The same organic filler, dispersant and xyleneReference Example 8Was dispersed in the same manner. further,Reference Example 8The same binder resin as above is dissolved in the above toluene and added to the filler dispersion, and mixed to form a surface layer coating solution (threeratio5)created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 6 shows.
[0185]
referenceComparative example6
  Reference Example 9In the same manner as above, toluene containing 2 ppm or more of chlorine ions was prepared. next,Reference Example 8As well as providing an undercoat layer, a charge generation layer, and a charge transport layer,Reference Example 15The same alumina, dispersant and cyclohexanoneReference Example 15Was dispersed in the same manner. further,Reference Example 15The same binder resin and charge transport material as above are dissolved in toluene and added to the filler dispersion, and mixed to form a surface layer coating solution (threeratio6)created. This liquid was applied by spraying to provide a surface layer of about 3.0 μm, and after drying, an electrophotographic photosensitive member was obtained.
  Chlorine ion concentration, volume average particle size, sedimentation test result of the surface layer coating liquid, initial image of the photoreceptor provided with the surface layer, image evaluation result after running 10,000 sheets, and weight loss of the surface layer Table 6 shows.
[0186]
referenceComparative example7
  Reference Example 8As well as an undercoat layer, a charge generation layer, a charge transport layer, and an electrophotographic photosensitive member without a surface layer (threeratio7)
  Table 6 shows the initial image of the photoreceptor, the image evaluation results after running 10,000 sheets, and the wear loss of the surface layer (charge transport layer).
[0187]
[Table 6]

[0188]
Chlorine ion concentration was determined by semi-quantitative measurement of the separated water using an ion chromatograph by adding an equal amount of ion-exchanged water to the coating solution, shaking and leaving it to stand.
The volume average particle size was measured with CAPA700 manufactured by Horiba.
Sedimentation criteria
◎: No settling of dispersed particles after standing for 2 days
○: Allowed to stand for 1 day without sedimentation of dispersed particles
Δ: Allowed to stand for 1 day, partially disperse the dispersed particles
×: Allowed to stand for 1 day, all dispersed particles settled
[0189]
The photoconductor is mounted on the Ricoh Co., Ltd. copier IMAGIO MF200, the dark portion potential is set to 800 V and the light portion potential is set to 100 V, an image (initial) is taken out, and then a 10,000 sheet passing test is performed. The image (10,000 sheets) and the amount of wear (thickness difference before and after 10,000 sheets) were measured by the method.
The film thickness was measured with an eddy current film thickness meter Fischer Corp MMS manufactured by Fischer.
[0190]
【The invention's effect】
As described above, as is clear from the detailed and specific description, according to the first group of electrophotographic photoconductor manufacturing methods of the present invention, the filler can be dispersed in a small particle size, so that the dispersion stability is excellent. In addition, it is possible to provide a photoreceptor that can form a high-quality image that is highly durable and stable for repeated use. In addition, by using ketones and ethers, it is possible to create a filler-containing surface layer coating solution with better dispersion stability. By using this, high-quality images that are durable and stable for repeated use can be created. It is possible to provide a photoconductor that can be used. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be prepared, and by using a charge transport material, it is highly sensitive, durable, and can produce high-quality images that are stable against repeated use. The body can be provided. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created. By using a polymer charge transport material, high-sensitivity, more durable, and high-quality images that are stable against repeated use can be obtained. It is possible to provide a photoconductor that can form an image. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the use of inorganic pigments improves wear resistance, creating a high-quality image that is more durable and stable for repeated use. It is possible to provide a photoconductor that can be used. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the wear resistance is further improved by using silica, alumina, and titanium oxide, making it more durable and stable for repeated use. It is possible to provide a photoconductor that can form a high-quality image. In addition, since polyester resins, acrylic resins, or copolymers containing these structures, polycarboxylic acids, and organic fatty acids function as dispersants, it is possible to create filler-containing surface layer coating solutions with superior dispersion stability. By using this, it is possible to provide an excellent effect that it is possible to provide a photoconductor capable of forming a high-quality image that is highly durable and stable for repeated use.
In addition, according to the second group of electrophotographic photoconductor manufacturing methods of the present invention, the filler-containing surface layer coating solution excellent in dispersion stability can be obtained by suppressing the temperature rise in the pulverization step to 20 ° C. or less. By using this, it is possible to provide a photoreceptor that can form a high-quality image that is highly durable and stable for repeated use. In addition, since a polyester resin, an acrylic resin, or a copolymer containing these structures, polycarboxylic acid, or organic fatty acid functions well as a dispersant, a filler-containing surface layer coating solution with better dispersion stability can be obtained. By using this, it is possible to provide a photoconductor that can form a high-quality image that is highly durable and stable for repeated use. In addition, by using ketones and ethers, it is possible to create a filler-containing surface layer coating solution with better dispersion stability. By using this, high-quality images that are durable and stable for repeated use can be created. It is possible to provide a photoconductor that can be used. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the use of inorganic pigments improves wear resistance, creating a high-quality image that is more durable and stable for repeated use. It is possible to provide a photoconductor that can be used. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the wear resistance is further improved by using silica, alumina, and titanium oxide, making it more durable and stable for repeated use. It is possible to provide a photoconductor that can form a high-quality image. Also, by using a ball mill, the temperature rise during pulverization can be suppressed to a small level, so it is possible to create a filler-containing surface layer coating solution with better dispersion stability, which makes it highly durable and can be used repeatedly. On the other hand, it is possible to provide a photoconductor that can form a stable high-quality image. Also, by using alumina balls with a diameter of φ1 mm or more and φ10 mm or less in the ball mill, the temperature rise during pulverization can be suppressed to a smaller level. By using it, it is possible to provide a photoreceptor that can form a high-quality image that is highly durable and stable for repeated use. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be prepared, and by using a charge transport material, it is highly sensitive, durable, and can produce high-quality images that are stable against repeated use. The body can be provided. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created. By using a polymer charge transport material, high-sensitivity, more durable, and high-quality images that are stable against repeated use can be obtained. An excellent effect is achieved in that a photoconductor capable of forming an image can be provided.
Furthermore, according to the third group of electrophotographic photoconductor manufacturing methods of the present invention, a filler-containing surface layer coating solution having excellent dispersion stability can be created by regulating the chlorine ion concentration to 1 ppm or less. It is possible to provide a photosensitive member that can form a high-quality image that is highly durable and stable for repeated use. In addition, by reducing the chlorine ion concentration in the solvent to 1 ppm or less using an ion adsorbent, it is possible to create a filler-containing surface layer coating solution with excellent dispersion stability, which is highly durable and stable against repeated use. It is possible to provide a photoconductor that can form a high-quality image. Moreover, as an ion adsorbent, more chlorine ions can be removed by using activated clay, florisil, basic alumina, and a filler-containing surface layer coating solution excellent in dispersion stability can be created. It is possible to provide a photosensitive member that can form a high-quality image that is highly durable and stable for repeated use. Also, by adding a dispersant, it is possible to create a filler-containing surface layer coating solution that is more excellent in dispersion stability. By using this, a high-quality image that is highly durable and stable for repeated use can be formed. A photoconductor can be provided. In addition, since a polyester resin, an acrylic resin, or a copolymer containing these structures, a monocarboxylic acid, or an organic fatty acid functions well as a dispersant, a filler-containing surface layer coating solution that is more excellent in dispersion stability is used. By using this, it is possible to provide a photoconductor that can form a high-quality image that is highly durable and stable for repeated use. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the use of inorganic pigments improves wear resistance, creating a high-quality image that is more durable and stable for repeated use. It is possible to provide a photoconductor that can be used. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created, and the wear resistance is further improved by using silica, alumina, and titanium oxide, making it more durable and stable for repeated use. It is possible to provide a photoconductor that can form a high-quality image. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be prepared, and by using a charge transport material, it is highly sensitive, durable, and can produce high-quality images that are stable against repeated use. The body can be provided. In addition, a filler-containing surface layer coating solution with excellent dispersion stability can be created. By using a polymer charge transport material, high-sensitivity, more durable, and high-quality images that are stable against repeated use can be obtained. An excellent effect is achieved in that a photoconductor capable of forming an image can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration example of an electrophotographic photosensitive member of the present invention.
FIG. 2 is a cross-sectional view illustrating another configuration example of the electrophotographic photosensitive member of the present invention.
FIG. 3 is a schematic view of an electrophotographic apparatus and a process cartridge for an electrophotographic apparatus according to the present invention.
FIG. 4 is a schematic view showing another electrophotographic apparatus of the present invention.
FIG. 5 is a schematic view showing another process cartridge of the present invention.
[Explanation of symbols]
1 Conductive support
2 Photosensitive layer
3 Surface layer
4 Charge generation layer
5 Charge transport layer
11 photoconductor
12 Static elimination lamp
13 Charger charger
14 Eraser
15 Image exposure unit
16 Development unit
17 Pre-transfer charger
18 Registration Roller
19 Transfer paper
20 Transcription charger
21 Separate charger
22 Separating nails
23 Cleaning charger
24 Fur Brush
26 photoconductor
27 Charger Charger
28 Cleaning brush
29 Image exposure unit
30 Development roller
31 photoconductor
32a Drive roller
32b Drive roller
33 Charger
34 Image exposure source
35 Transcription Charger
36 Exposure before cleaning
37 Cleaning brush
38 Static elimination light source

Claims (11)

  In a method for producing an electrophotographic photosensitive member comprising at least a photosensitive layer and a surface layer containing a binder resin and a filler on a conductive support, pulverization in which a filler is dispersed in a solvent and a binder resin using a dispersant. A method for producing an electrophotographic photosensitive member, wherein an increase in liquid temperature in a step or a pulverizing step of dispersing a filler in a solvent using a dispersant is 20 ° C. or less. The dispersant used in the filler dispersion step is characterized by adding a polyester resin, an acrylic resin, or a copolymer containing these structures, a monocarboxylic acid, and an organic fatty acid alone or in a mixture of two or more. The method for producing an electrophotographic photosensitive member according to claim 1 . The process of the filler dispersion, at least ketones, process for producing an electrophotographic photosensitive member according to claim 1 or 2, characterized by using a solvent selected from ethers. The method for producing an electrophotographic photosensitive member according to any one of claims 1 to 3, characterized in that the inclusion of the charge transport material in the coating solution for the surface layer. 5. The method for producing an electrophotographic photosensitive member according to claim 4 , wherein the charge transport material contained in the surface layer coating solution is a polymer charge transport material. The method for producing an electrophotographic photosensitive member according to any one of claims 1 to 5 filler dispersed in the coating liquid for the surface layer is characterized in that an inorganic pigment. The method for producing an electrophotographic photosensitive member according to claim 6 , wherein the inorganic pigment dispersed in the coating liquid for the surface layer is one selected from silica, alumina, and titanium oxide. The method for producing an electrophotographic photosensitive member according to claim 1 , wherein a ball mill is used for dispersing the filler. 9. The method for producing an electrophotographic photosensitive member according to claim 8 , wherein balls having a diameter of 1 mm or more and 10 mm or less are used as the dispersion medium. An electrophotographic photosensitive member, characterized in that it is produced by the production method according to any one of claims 1 to 9. At least charging means, image exposure means, developing means, transferring means, a cleaning means, the electrophotographic apparatus comprising comprises a discharging means and an electrophotographic photosensitive member, the electrophotographic of claim 10 as the electrophotographic photosensitive member An electrophotographic apparatus using a photoconductor.

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