JP2004145100A - Electrophotographic device and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic device and a process cartridge excellent in a cleaning performance without using lubricant inside or on a photoreceptor layer, and capable of supplying a high definition image while maintaining high image quality without causing a defective image and the characteristic deterioration at repeatedly outputting images, as for the electrophotographic device using small grain toner. <P>SOLUTION: In an electrophotographic device equipped with a cleaning means constituted so that the contact pressure of a cleaning blade against an electrophotographic photoreceptor is ≥60 g/cm, an organic photoconductive photoreceptor is used as the electrophotographic photoreceptor for the electrophotographic device and the process cartridge. Besides, the contact angle of the surface with respect to deionized water is 60-85°, and the dynamic friction coefficient to the cleaning blade is 0.2-1.4. In the electrophotographic device using the small grain toner, the electrophotographic device and the process cartridge excellent in the cleaning performance without using the lubricant inside or on the photosensitive layer, and capable of supplying the image of high image quality and high definition without causing defective image and deterioration of characteristics at the time of repeatedly outputting images can be obtained. <P>COPYRIGHT: (C)2004,JPO

Description

【００５１】
式中、Ｒ_１及びＲ_２はそれぞれ独立に、ハロゲン原子、置換されてもよいアルキル基、アリール基又はアルキレン基であり、ａ及びｂはそれぞれ独立に０〜４の整数であり、Ｘは単結合、−Ｏ−、−Ｓ−又は−ＣＲ_３Ｒ_４−である。Ｒ_３及びＲ_４は水素原子、ハロゲン原子、アルキル基、アリール基又はＲ_５とＲ_６が結合することによって形成されるアルキリデン基である。
【００５２】
【化４】

【００５３】
式中、Ｒ_５及びＲ_６はそれぞれ独立に、ハロゲン原子、置換されてもよいアルキル基、アリール基又はアルキレン基であり、ｃ及びｄはそれぞれ独立に０〜４の整数である。
【００５４】
電荷輸送層には更に、電荷輸送層中に酸化防止剤、紫外線吸収剤、可塑剤又は公知の電荷輸送材料を必要に応じて添加することもできる。次に図３に本発明の電子写真感光体を有するプロセスカートリッジを備えた電子写真装置の概略構成を示す。
【００５５】
図３において、２１はドラム状の本発明の電子写真感光体であり、軸２２を中心に矢印方向に所定の周速度（プロセススピード）をもって回転駆動される。電子写真感光体２１は、回転過程において、一次帯電手段２３によりその周面に正又は負の所定電位の均一帯電を受け、次いで、スリット露光やレーザービーム走査露光等の露光手段（不図示）から出力される目的の画像情報の時系列電気デジタル画像信号に対応して強度変調された露光光２４を受ける。こうして電子写真感光体２１の周面に対し、目的の画像情報に対応した静電潜像が順次形成されていく。
【００５６】
形成された静電潜像は、次いで現像手段５内の荷電粒子（トナー）で正規現像又は反転現像により可転写粒子像（トナー像）として顕画化され、不図示の給紙部から電子写真感光体２１と転写手段２６との間に電子写真感光体２１の回転と同期して取り出されて給送された転写材２７に、電子写真感光体２１の表面に形成担持されているトナー像が転写手段２６により順次転写されていく。この時、転写手段にはバイアス電源（不図示）からトナーの保有電荷とは逆極性のバイアス電圧が印加される。
【００５７】
トナー画像の転写を受けた転写材２７は、電子写真感光体面から分離されて像定着手段２８へ搬送されてトナー像の定着処理を受けることにより画像形成物（プリント、コピー）として装置外へプリントアウトされる。
【００５８】
トナー像転写後の電子写真感光体２１の表面は、クリーニング手段２９によって転写残りトナー等の付着物の除去を受けて清浄面化される。近年、クリーナレスシステムも研究され、転写残りトナーを直接、現像器等で回収することもできる。更に、前露光手段（不図示）からの前露光光３０により除電処理された後、繰り返し画像形成に使用される。なお、一次帯電手段２３が帯電ローラー等を用いた接触帯電手段である場合は、前露光は必ずしも必要ではない。
【００５９】
本発明においては、上述の電子写真感光体２１、一次帯電手段２３、現像手段２５及びクリーニング手段２９等の構成要素のうち、複数のものを容器に納めてプロセスカートリッジとして一体に結合して構成し、このプロセスカートリッジを複写機やレーザービームプリンター等の電子写真装置本体に対して着脱自在に構成してもよい。例えば、一次帯電手段２３、現像手段２５及びクリーニング手段２９の少なくとも１つを電子写真感光体２１と共に一体に支持してカートリッジ化して、装置本体のレール等の案内手段３２を用いて装置本体に着脱自在なプロセスカートリッジ３１とすることができる。
【００６０】
また、露光光２４は、電子写真装置が複写機やプリンターである場合には、原稿からの反射光や透過光、あるいは、センサーで原稿を読取り、信号化し、この信号に従って行われるレーザービームの走査、ＬＥＤアレイの駆動又は液晶シャッターアレイの駆動等により照射される光である。
【００６１】
本発明の電子写真感光体は、電子写真複写機に利用するのみならず、レーザービームプリンター、ＣＲＴプリンター、ＬＥＤプリンター、ＦＡＸ、液晶プリンター及びレーザー製版等の電子写真応用分野にも幅広く適用し得るものである。
【００６２】
【実施例】
以下に、具体的な実施例を挙げて本発明を更に詳細に説明する。ただし、本発明の実施の形態は、これらに限定されるものではない。なお、実施例中の「部」は「質量部」を意味する。
【００６３】
＜感光体の製造例１＞
長さ２６０．５ｍｍ、直径３０ｍｍ、シリンダー部の厚み０．７ｍｍ、最大表面粗さ５．０μｍ、平均表面粗さ１．０μｍのアルミニウムシリンダー（ＪＩＳＡ　３００３アルミニウムの合金）を用意した。
【００６４】
酸化スズの被覆層を有する硫酸バリウム粒子からなる粉体（パストランＰＣ１、三井金属鉱業（株）製）６０部、酸化チタン（ＴＩＴＡＮＩＸ　ＪＲ、テイカ（株）製）６０部、レゾール型フェノール樹脂（フェノライトＪ−３２５、大日本インキ化学工業（株）製、固形分７０％）７０部、シリコーンオイル（ＳＨ２８ＰＡ、東レシリコーン（株）製）１０部、シリコーン樹脂（トスパール１２０、東芝シリコーン（株）製）１０部、２−メトキシ−１−プロパノール６０部及びメタノール６０部からなる溶液を約２０時間、ボールミルで分散した。
【００６５】
このようにして調合した導電層用分散液を前述のアルミニウムシリンダー上に浸漬法によって塗布し、１４０℃で３０分間加熱硬化することにより、膜厚が１２μｍの樹脂層を形成した。
【００６６】
次に、共重合ナイロン樹脂（商品名：アミランＣＭ８０００、東レ（株）製）１０部とメトキシメチル化６ナイロン樹脂（商品名：トレジンＥＦ−３０Ｔ、帝国化学（株）製）３０部をメタノール４００部／ｎ−ブタノール２００部の混合液に溶解した溶液を、前記樹脂層の上に浸漬塗布し、９０℃で１０分間加熱乾燥して厚み０．６２μｍのバリア層を形成した。
【００６７】
次に下記式（３）のガリウムフタロシアニン顔料８．５部とポリビニルブチラール樹脂（商品名：エスレックＢＸ−１、積水化学工業（株）製）５部、シクロヘキサノン６０部からなる混合溶液をφ１ｍｍガラスビーズを用いたサンドミルで３時間分散した後、酢酸エチル１００部を加えて電荷発生層用塗工液を調製した。この塗工液を上記で作製した中間層上にバーコーティング法によって塗布し、９０℃で１０分間加熱乾燥して、膜厚が０．０８μｍの電荷発生層を形成した。
【００６８】
【化５】

式中、Ｘはそれぞれ独立にＣｌ又はＢｒ基を示す。ｍ、ｎ、ｐ及びｋはそれぞれ独立に０〜４の整数を示す。
【００６９】
次に、以下の材料を溶解調整して電荷輸送層用塗工液を作製した。
【００７０】
下記式（４）で示される電荷輸送材料　　　　４０部
下記式（５）で示されるのポリアリレート　　５０部
（粘度平均分子量１０５０００）
クロロベンゼン　　　　　　　　　　　　　３５０部
【００７１】
【化６】

【００７２】
【化７】

【００７３】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２５μｍの電荷輸送層を形成した。
【００７４】
この時、表面層の水に対する接触角を、以下のように測定したところ、７８°であった。
【００７５】
＜接触角の測定法＞
接触角の測定は常温常湿（２５℃／５０％ＲＨ）において純水を用い、装置は協和界面科学（株）製接触角形ＣＡ−ＤＳ型を用いた。接触角は感光体表面５点の平均値とし、水滴付着後１分以内に測定した。
【００７６】
また、表面層の動摩擦係数を以下のように測定したところ、１．２であった。
【００７７】
＜動摩擦係数の測定法＞
感光体表面の動摩擦係数（μ）の測定は、常温常湿（２５℃／５０％ＲＨ）において図４の概略断面図に示されるクリーニングブレード固定装置を｛ＨＥＩＤＯＮ社製の表面試験装置（型式ＨＥＩＤＯＮ−１４）｝を用いた。この装置は、ブレード７を一定の荷重（ｇ）で電子写真感光体６に押し当て、感光体面と平行に動いている時に加わる力（ｇ）を測定する。動摩擦係数はブレードが動いている時の〔感光体に加わる力（ｇ）〕／〔ブレードに加えた荷重（ｇ）〕から求められる。使用ブレードは北辰工業社製ウレタンブレード（ゴム硬度６７°）を５ｍｍ×３０ｍｍ×２ｍｍにカットし、荷重１０ｇでｗｉｔｈ方向、角度２０°にて測定した。
【００７８】
＜感光体の製造例２＞
感光体製造例１と同様に電荷発生層まで設けた。
【００７９】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【００８０】
式（４）の電荷輸送材料　　　　　　　　　　　　２５部
式（５）のポリアリレート　　　　　　　　　　　５０部
くし型シリコーン　　　　　　　　　　　　　０．７５部
（アロンＧＳ１０１ＣＰ、東亜合成化学工業（株）製）
クロロベンゼン　　　　　　　　　　　　　　　３００部
下記式（６）のシリコーン変性ポリカーボネート　　５部
（粘度平均分子量４００００）
【００８１】
【化８】

【００８２】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚が２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は８５°であった。また、表面層の動摩擦係数は０．５であった。
【００８３】
＜感光体の製造例３＞
感光体製造例１と同様に電荷発生層まで設けた。
【００８４】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【００８５】
式（３）の電荷輸送材料　　　　　　　　　　　　２５部
式（５）のポリアリレート　　　　　　　　　　　５０部
クロロベンゼン　　　　　　　　　　　　　　　３００部
下記式（７）のシリコーン変性ポリカーボネート　　５部
（粘度平均分子量４００００）
【００８６】
【化９】

【００８７】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は８５°であった。また、表面層の動摩擦係数は１．４であった。
【００８８】
＜感光体の製造例４＞
感光体製造例１と同様に電荷発生層まで設けた。
【００８９】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【００９０】
式（４）の電荷輸送材料　　　　　　　　　　　　６０部
式（５）のポリアリレート　　　　　　　　　　　５０部
くし型シリコーン　　　　　　　　　　　　　０．７５部
（アロンＧＳ１０１ＣＰ、東亜合成化学工業（株）製）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【００９１】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は６０°であった。また、表面層の動摩擦係数は０．５であった。
【００９２】
＜感光体の製造例５＞
感光体製造例１と同様に電荷発生層まで設けた。
【００９３】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【００９４】
式（３）の電荷輸送材料　　　　　　　　　　　　５４部
下記式（８）の電荷輸送材料　　　　　　　　　　　６部
式（５）のポリアリレート　　　　　　　　　　　５０部
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【００９５】
【化１０】

【００９６】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は６０°であった。また、表面層の動摩擦係数は０．５であった。
【００９７】
＜感光体の製造例６＞
感光体製造例１と同様に電荷発生層まで設けた。
【００９８】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【００９９】
下記式（９）の電荷輸送材料　　　　　　　　　　６０部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
くし型シリコーン　　　　　　　　　　　　　０．７５部
（アロンＧＳ１０１ＣＰ、東亜合成化学工業（株）製）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【０１００】
【化１１】

【０１０１】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は７５°であった。また、表面層の動摩擦係数は０．４であった。
【０１０２】
＜感光体の製造例７＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１０３】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１０４】
式（９）の電荷輸送材料　　　　　　　　　　　　５４部
式（８）の電荷輸送材料　　　　　　　　　　　　　６部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【０１０５】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は７５°であった。また、表面層の動摩擦係数は１．４であった。
【０１０６】
＜感光体の製造例８＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１０７】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１０８】
式（９）の電荷輸送材料　　　　　　　　　　　　４０部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
クロロベンゼン　　　　　　　　　　　　　　　３５０部
【０１０９】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は９５°であった。また、表面層の動摩擦係数は１．０であった。
【０１１０】
＜感光体の製造例９＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１１１】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１１２】
式（９）の電荷輸送材料　　　　　　　　　　　　７５部
ポリカーボネート　　　　　　　　　　　　　　　４５部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【０１１３】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は５７°であった。また、表面層の動摩擦係数は１．０であった。
【０１１４】
＜感光体の製造例１０＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１１５】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１１６】
式（９）の電荷輸送材料　　　　　　　　　　　　４０部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
くし型シリコーン　　　　　　　　　　　　　０．９５部
（アロンＧＳ１０１ＣＰ、東亜合成化学工業（株）製）
クロロベンゼン　　　　　　　　　　　　　　　３５０部
【０１１７】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は９５°であった。また、表面層の動摩擦係数は０．４であった。
【０１１８】
＜感光体の製造例１１＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１１９】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１２０】
式（９）の電荷輸送材料　　　　　　　　　　　　３６部
式（８）の電荷輸送材料　　　　　　　　　　　　　４部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
クロロベンゼン　　　　　　　　　　　　　　　３５０部
【０１２１】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は９５°であった。また、表面層の動摩擦係数は１．４であった。
【０１２２】
＜感光体の製造例１２＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１２３】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１２４】
式（９）の電荷輸送材料　　　　　　　　　　　　４０部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
くし型シリコーン　　　　　　　　　　　　　０．９５部
（アロンＧＳ１０１ＣＰ、東亜合成化学工業（株）製）
クロロベンゼン　　　　　　　　　　　　　　　３５０部
【０１２５】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は５５°であった。また、表面層の動摩擦係数は０．４であった。
【０１２６】
＜感光体の製造例１３＞
感光体製造例１と同様に電荷発生層まで設けた。
【０１２７】
次に、以下の材料を用いて電荷輸送層用塗工液を作製した。
【０１２８】
式（９）の電荷輸送材料　　　　　　　　　　　　７０部
式（８）の電荷輸送材料　　　　　　　　　　　　　５部
ポリカーボネート　　　　　　　　　　　　　　　５０部
（ユーピロンＺ−２００、三菱ガス化学（株）製）
式（７）のシリコーン変性ポリカーボネート　　　　５部
（粘度平均分子量４００００）
クロロベンゼン　　　　　　　　　　　　　　　４００部
【０１２９】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚２０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角は５５°であった。また、表面層の動摩擦係数は１．５であった。
【０１３０】
＜感光体の製造例１４＞
感光体製造例１と同様に中間層まで設けた。
【０１３１】
次に、下記式（１０）のアゾ顔料７．５部とポリビニルブチラール樹脂（商品名：エスレックＢＸ−１、積水化学工業（株）製）５部、ＴＨＦ６０部からなる混合溶液をφ１ｍｍガラスビーズを用いたサンドミルで３時間分散した後、シクロヘキサノン１００部を加えて電荷発生層用塗工液を調製した。この塗工液を上記で作製した中間層上にバーコーティング法によって塗布し、９０℃で１０分間加熱乾燥して、膜厚が０．０８μｍの電荷発生層を形成した。
【０１３２】
【化１２】

式中、Ｘはそれぞれ独立にＣｌ又はＢｒ基を示す。ｍ、ｎ、ｐ及びｋはそれぞれ独立に０〜４の整数を示す。
【０１３３】
次に、以下の材料を溶解調整して電荷輸送層用塗工液を作製した。
【０１３４】
式（４）で示される電荷輸送材料　　　　　　　　　３６部
式（８）で示される電荷輸送材料　　　　　　　　　　４部
下記式（１１）で示されるのポリアリレート　　　　５０部
（粘度平均分子量１３００００）
クロロベンゼン　　　　　　　　　　　　　　　　３５０部
【０１３５】
【化１３】

【０１３６】
この電荷輸送層用塗工液を、上記電荷発生層上に浸漬塗布し、１２０℃で１時間加熱乾燥して、膜厚３０μｍの電荷輸送層を形成した。この時、表面層の水に対する接触角を、以下のように測定したところ、７８°であった。
【０１３７】
＜トナー製造例１＞
高速攪拌装置ＴＫ式ホモミキサー（特殊機化工業社製）を備えた２リットル用４ツ口フラスコ中にイオン交換水６００ｇと０．１ｍｏｌ／リットル−Ｎａ_３ＰＯ_４水溶液５００ｇを投入し、回転数を１４０００ｒｐｍに調整し、６５℃に加温した。ここに、１．０ｍｏｌ／リットル−ＣａＣｌ_２水溶液７０部を徐々に添加し、微小な難水溶性分散安定剤Ｃａ_３（ＰＯ_４）_２を含む水系分散媒体を調整した。
【０１３８】
一方、分散質として、
スチレン　　　　　　　　　　　　　　　　　　　７８部
ｎ−ブチルアクリレート　　　　　　　　　　　　２２部
ジビニルベンゼン　　　　　　　　　　　　　　０．２部
カーボンブラック（ＢＥＴ比表面積５０ｍ^２／ｇ）　５部
不飽和ポリエステル（エポキシ化ビスフェノールＡをフマル酸の縮合重合体、
ピーク分子量＝７０００）　　　　　　　　　　　　　４部
ジ−ｔｅｒｔ−ブチルサリチル酸のクロル化合物　　２部
エステルワックス（ｍｐ＝６２℃）　　　　　　　１０部
【０１３９】
上記混合物をアトライター（三井金属社製）を用い３時間分散させた後、２，２’−アゾビス（２，４−ジメチルバレロニトリル）５部を添加し、重合性単量体組成物を調製した。
【０１４０】
次に、前記水系分散媒体中に該重合性単量体組成物を投入し、内温６５℃のＮ_２雰囲気下で、高速攪拌器の回転数を１２０００ｒｐｍに維持しつつ、１５分間攪拌し、該重合性単量体組成物を造粒した。その後、攪拌器をプロペラ攪拌羽に代え５０ｒｐｍで攪拌しながら同温度で１０時間保持して重合を完了した。
【０１４１】
重合終了後、懸濁液を冷却し、次いで希塩酸を添加し分散安定剤を除去した。更に、水洗浄を数回繰り返した後、流動層乾燥機（大川原製作所社製）を用い熱風中で攪拌しながら１０時間トナー粒子の球形化処理と乾燥処理を行い、重合体粒子（Ａ）を得た。該重合体粒子（Ａ）は、円相当個数平均径が４．１μｍであった。
【０１４２】
上記重合体粒子（Ａ）１００部と疎水性オイル処理シリカ微粒子（ＢＥＴ：２００ｍ^２／ｇ）２部をヘンシェルミキサーで乾式混合して、トナー（Ａ）を調製した。
【０１４３】
＜トナー製造例２＞
高速攪拌器の回転数を１８０００ｒｐｍ、流動層乾燥機の処理時間を２０時間に変更した以外は、トナー製造例１と同様にしてトナーを製造した。このトナーの円相当個数平均径は２．３μｍであった。
【０１４４】
＜トナー製造例３＞
高速攪拌器の回転数を８０００ｒｐｍ、流動層乾燥機の処理時間を５時間に変更した以外は、トナー製造例１と同様にしてトナーを製造した。このトナーの円相当個数平均径は７．０μｍであった。
【０１４５】
＜トナー製造例４＞
スチレン−ｎ−ブチルアクリレート−ジビニルベンゼン樹脂　１００部
（ピーク分子量＝１５０００、Ｍｗ／Ｍｎ＝２．４、Ｔｇ＝５０℃）
トナーの製造例１で用いた不飽和ポリエステル　　　　　　　　　４部
トナーの製造例１で用いたカーボンブラック　　　　　　　　　　５部
負荷電性制御剤（モノアゾ系鉄錯体）　　　　　　　　　　　　　２部
トナー製造例１で用いたエステルワックス　　　　　　　　　　１０部
【０１４６】
上記混合物を二軸エクストルーダーで溶融混練し、冷却した混練物をハンマーミルで粗粉砕し、租粉砕物をジェットミルで微粉砕し、得られた微粉砕物を市販のリン酸カルシウム微粉体とをヘンシェルミキサーで混合後、得られた混合紛体を水が入っている容器へ投入し、更にホモニキサーを用い水中に分散させ、水温を徐々に昇温させ温度６０℃で２時間加熱処理した。その後、希塩酸を容器に添加し、微粉砕物粒子の表面のリン酸カルシウムを十分溶解した。濾別後に洗浄、乾燥し、次いで４００メッシュの篩いを通して凝集物を除いた後、分級してトナー（Ｄ）とした。トナー製造例１と同様にしてトナー（Ｄ）を調製した。このトナーの円相当個数平均径は８．２μｍであった。
【０１４７】
＜トナー製造例５＞
分散剤として、
エチレン　　　　　　　　　　　　　　　　　　　　　　　　８０部
アクリル酸２−エチルヘキシル　　　　　　　　　　　　　　２０部
ジビニルベンゼン　　　　　　　　　　　　　　　　　　　０．３部
カーボンブラック（ＢＥＴ比表面積＝５０ｍ^２／ｇ）　　　　　　７部
スピロンブラックＴＲＨ（保土ヶ谷化学工業（株）製）　　　　１部
ポリプロピレン（ビスコール５５０Ｐ、三洋化成（株）製）　１０部
２，２’−アゾビス（２，４−ジメチルバレロニトリル）　　　３部
をサンドミルで十分に混合し重合成組成物を得た。
【０１４８】
この重合成組成物をリン酸三カルシウム１部及びドデシルベンゼンスルホン酸ナトリウム０．０１部を分散安定剤として含む水中に加え、内温６５℃のＮ_２雰囲気下で、高速攪拌器にて分散させて懸濁液を得た。その後、この懸濁液を攪拌機を備えた三ツ口フラスコに入れ、攪拌下、７０℃で１０時間加熱して重合させた後、塩酸水溶液にてリン酸三カルシウムを除去し、水洗浄の後、乾燥させてトナーを得た。この重合トナー１００部に疎水性シリカ微粉末（商品名：アエロジルＲ−９７２、アエロジル（株）製）０．３部を加えて混合し、トナー（Ｅ）を得た。このトナーの円相当個数平均径は１１．２μｍであった。
【０１４９】
（実施例１）
本発明の電子写真装置の実施例を説明する。電子写真装置として、ヒューレットパッカード製ＬＢＰ（商品名：レーザージェット４０００、プロセススピード：９４．２ｍｍ／ｓｅｃ）を用いた。
【０１５０】
クリーニングブレードの感光体に対する当接圧を７０ｇ／ｃｍとし、電子写真感光体は感光体製造例１で示したものを装着した。
【０１５１】
現像装置は以下のように改造した。トナー供給耐であるマグネットを内包したアルミニウムスリーブの代わりにカーボンブラックを分散して抵抗を調整したシリコーンゴムからなる中抵抗ゴムローラをトナー担持体として、電子写真感光体に当接した。トナー担持体の表面の移動方向及び回転速度は、電子写真感光体との接触部において同方向であり、電子写真感光体の回転速度に対して１５０％となるように駆動する。トナー担持体のトナーを塗布しる手段をしては、塗布ローラーをトナー担持体に当接させ、トナー担持体と逆方向に回転させてトナーと塗布した。更に、トナーはトナー製造例１で示したものに入れ替えた。
【０１５２】
本体及び電子写真感光体及びトナー構成を表１に示す。
【０１５３】
このＬＢＰを３０℃／８０％ＲＨの環境下に設置し、１００００枚の連続コピーを行い画像評価を行った。感光体への印加電圧として、ＤＣバイアス−６２０Ｖを印加し、更に周波数１６００Ｈｚ、１３００μＡのＡＣバイアスを重畳することによって感光体サンプル表面を帯電し、その時のレーザー光非照射時帯電電位Ｖｄを−６００Ｖとした。また続いてレーザー光を照射し明部電位Ｖｌを−１４０Ｖとした。レーザー光の光量は０．３μＪ／ｃｍ^２とした。
【０１５４】
耐久の結果、クリーニング不良は発生せず、ブレードのめくれも発生しなかった。１００００枚耐久による感光体の摩耗量は１．５μｍであり、耐久前後の画像濃度やドット再現性も良好であった。画像濃度はベタ画像を出力し確認した。また、ドット再現性は図５のような孤立ドット画像を出力し、ルーペを用いて確認した。結果を表２に示す。
【０１５５】
（実施例２〜１１）
本体、クリーニングブレード当接圧、電子写真感光体及びトナー構成は表１に示すとおりに設定し、実施例１と同様に評価を行った。結果を表２に示す。
【０１５６】
（比較例１〜１２）
本体、クリーニングブレード当接圧、電子写真感光体及びトナー構成は表１に示すとおりに設定し、実施例１と同様に評価を行った。結果を表２に示す。
【０１５７】
【表１】

【０１５８】
【表２】

【０１５９】
【発明の効果】
上述したように、本発明によって、小径トナーを用いた電子写真装置において、感光層内又は表面上に潤滑剤を用いることなく、クリーニング性に優れ、繰り返し画像出力時における画像欠陥及び特性悪化を起こさず、高い画像品質とかつ高精細な画像の供給が可能となる電子写真装置及びプロセスカートリッジを提供することが可能となった。
【図面の簡単な説明】
【図１】電子写真感光体とクリーニングブレードの断面構成図である。
【図２】ブレード当接圧の測定方法の例を示す図である。
【図３】本発明の電子写真感光体を有するプロセスカートリッジを備えた電子写真装置の概略構成の例を示す図である。
【図４】電子写真感光体表面の動摩擦係数を測定するクリーニングブレード固定装置の概略断面図である。
【図５】孤立ドット画像の出力例を示す図である（１マス＝４２μｍ×４２μｍ）。
【符号の説明】
１　支柱
２　ホルダー支柱アーム
３　上部ホルダー
４　下部ホルダー
５　固定ビス
６　サンプル
７　ウレタンゴムブレード
１２ａ　感光体ドラム
１３ａ　クリーニングブレード
２１　電子写真感光体
２２　軸
２３　帯電手段
２４　露光光
２５　現像手段
２６　転写手段
２７　転写材
２８　定着手段
２９　クリーニング手段
３０　前露光光
３１　プロセスカートリッジ
３２　案内手段
５６　駆動モータ
５７　移動可能なブレード台
５８　荷重センサー
５９　アンプ
６０　電位計[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrophotographic apparatus and a process cartridge. More specifically, in an electrophotographic apparatus having a cleaning blade, the contact pressure of the cleaning blade against the electrophotographic photosensitive member, the contact angle of the surface layer of the electrophotographic photosensitive member, and the coefficient of kinetic friction are determined. The present invention relates to a specified electrophotographic apparatus and a process cartridge.
[0002]
[Prior art]
2. Description of the Related Art In recent years, with the rapid development of the information industry, high-quality image recording has been desired for industrial or office use. To meet these demands, various methods such as an electrophotographic method, a thermal transfer method, and an ink-jet method have been proposed and put to practical use. Among them, the electrophotographic method is widely used in offices because of its advantages of high-speed printability and high image quality.However, in recent years, cases of recording of graphic image quality have been increasing, and further higher image quality and higher definition are required. It has been demanded. In response to these market demands, laser printers have been increasing their resolution from conventional 240 dpi to 600 and 1200 dpi, and the digital image and high resolution of copiers have been promoted. And higher definition are being promoted.
[0003]
In response to these movements, the development of precision processing technology, the development and use of high-precision control technology, etc. have been proposed and studied from the equipment development side, and the toner development Technology development for higher image quality and higher definition is being actively conducted. In the improvement of the reduction in the diameter of the toner, a conventional pulverization method of kneading, pulverizing, and classifying a colorant and a binder resin to obtain a toner requires finer pulverization, classification means, and reduction in diameter by post-processing such as polishing. Actively studied. On the other hand, a polymerized toner obtained by dispersing an ethylenically unsaturated monomer containing a colorant in water in the presence of a dispersant and then polymerizing is attracting attention, and has been vigorously researched and developed. It has been confirmed that a polymerized toner is an effective means for improving the diameter of a toner. As described above, the small-diameter toner has a great effect in improving the image quality and definition by developing the electrostatic latent image on the electrophotographic photoreceptor faithfully and accurately and exhibiting high transferability. However, on the other hand, there is a drawback that cleaning properties are low, and problems such as poor cleaning frequently occur during a printing test with a copying machine or a printer.
[0004]
In an electrophotographic apparatus such as a copying machine or a printer, after a toner image formed on the surface of an electrophotographic photosensitive member is transferred to a transfer material, untransferred toner remains on the surface of the electrophotographic photosensitive member, and the remaining toner is a brush. , Is removed from the surface of the electrophotographic photosensitive member by a magnetic brush or a blade. For brush cleaning, polyester or acrylic fibers are used, and the shape is changed to a loop shape or a straight hair shape, and the hardness and thickness of the fibers are changed for optimization. However, cleaning with only a brush cannot remove fine powder toner and slips through between fibers, resulting in insufficient removal. The same holds true for the magnetic brush. Attempts have also been made to remove electrostatically by applying an electric field, but toner scattering is not sufficient. Therefore, at present, blade cleaning using an elastic blade is mainly used from the viewpoint of removing residual toner, reducing cost and reducing the diameter.
[0005]
There have been many reports on improving blade cleaning, which are disclosed in numerous patent publications. For example, Patent Literature 1 discloses a study result of physical properties such as hardness, elastic modulus and elongation of urethane rubber blades and cleaning properties.
[0006]
Further, Japanese Patent Application Laid-Open No. H11-163873 discloses the result of studying the cleaning characteristics by setting the toner particle size and the cleaning blade.
[0007]
As described above, the blade cleaning has high cleaning performance even when compared with other methods. However, when cleaning the small-diameter toner described above, sufficient cleaning performance is exhibited in all environments where a copier or a printer is used. This is difficult, and even under the cleaning conditions described in the above publication, cleaning failure occurs particularly in an environment of high temperature and high humidity or low temperature and low humidity, and the solution has not yet been sufficiently solved.
[0008]
At present, as an electrophotographic photosensitive member used in an electrophotographic apparatus, an organic photoconductive photosensitive member is often used for reasons such as production cost and chemical stability. Most of the organic photoreceptors are composed of two layers, a charge generation layer and a charge transport layer. In the cleaning, the charge transport layer comes into contact with the toner and the blade and slides. Therefore, the surface of the electrophotographic photosensitive member is damaged and worn. Scratches and uneven wear of the photosensitive layer cause uneven contact between the cleaning blade and the surface of the electrophotographic photosensitive member, and this causes cleaning failure. Therefore, when blade cleaning is performed on a conventional organic photoreceptor, there is a tendency that cleaning failure is likely to occur during repeated use. When the contact pressure of the cleaning blade on the surface of the electrophotographic photosensitive member is increased to improve the cleaning performance, the initial cleaning performance is improved. In addition to an increase in the amount of abrasion, there is a problem that the cleaning blade is turned up under high temperature and high humidity.
[0009]
On the other hand, the amount of damage to the drum and the amount of wear can be reduced by adding a lubricant such as silicone resin fine particles or fluorine resin fine particles to the photosensitive layer, or by applying a lubricant to the surface of the photosensitive member. However, the addition of such a lubricant tends to deteriorate the latent image on the photoreceptor, resulting in deterioration of image quality, and deterioration of characteristics such as sensitivity characteristics and memory characteristics. Further, means such as application of a lubricant onto the photoreceptor complicates the apparatus configuration and causes a cost increase.
[0010]
As described above, the small-diameter toner faithfully and accurately develops an electrostatic latent image on an electrophotographic photoreceptor, and has an effect on high image quality and high definition by exhibiting high transferability. On the other hand, in a system using an organic photoreceptor and a cleaning blade, which has low cleaning properties and is advantageous for cost reduction and diameter reduction, it is extremely difficult to perform stable cleaning in all use environments, and it has been completely solved. Not yet.
[0011]
[Patent Document 1]
JP-A-5-35156
[Patent Document 2]
JP-A-9-292722
[0012]
[Problems to be solved by the invention]
An object of the present invention is to provide an electrophotographic apparatus using a small-diameter toner, without using a lubricant in or on a surface of a photosensitive layer, having excellent cleaning properties, and not causing image defects and characteristic deterioration at the time of repeated image output. An object of the present invention is to provide an electrophotographic apparatus and a process cartridge capable of supplying a high-definition image while maintaining image quality.
[0013]
[Means for Solving the Problems]
According to the present invention, in an electrophotographic apparatus having a cleaning unit in which a contact pressure of a cleaning blade against an electrophotographic photosensitive member is 60 g / cm or more, the electrophotographic photosensitive member is an organic photoconductive photosensitive member, and pure water on the surface is used. An electrophotographic apparatus and a process cartridge, wherein a contact angle with respect to the cleaning blade is 60 ° or more and 85 ° or less and a dynamic friction coefficient with respect to the cleaning blade is 0.2 or more and 1.4 or less.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0015]
The present inventors have conducted intensive studies on the problem, and found that in an electrophotographic apparatus having a cleaning unit in which a contact pressure of a cleaning blade against a photoconductor is 60 g / cm or more, the photoconductor is made of an organic photoconductive photosensitive material. Wherein the contact angle of the surface of the photoreceptor to pure water is 60 ° or more and 85 ° or less, and the coefficient of kinetic friction of the photoreceptor with respect to the cleaning blade is 0.2 or more and 1.4 or less. It has been found that the above problems can be solved in a photographic device.
[0016]
Specifically, when toner having strict cleaning conditions is used, if the contact pressure of the cleaning blade against the photosensitive member is less than 60 g / cm, the toner slips through during repeated use. It was found that cleaning was established when the contact pressure of the cleaning blade with respect to was 60 g / cm or more.
[0017]
However, when the contact pressure of the cleaning blade with respect to the photoconductor is 60 g / cm or more, in addition to scratches on the photoconductor surface and an increase in abrasion in repeated image output, there is a problem that the cleaning blade is turned up at high temperature and high humidity. Therefore, it could not be used as it was.
[0018]
It is generally said that the larger the contact angle of the electrophotographic photosensitive member surface with pure water, the higher the slipperiness, abrasion resistance, and releasability of the toner and the like. However, in the present invention, the contact angle is 60 ° or more. When the contact pressure of the cleaning blade with respect to the photoreceptor is 60 g / cm or more, the contact pressure of the cleaning blade with respect to the photoreceptor is as small as 85 ° or less and the coefficient of kinetic friction of the photoreceptor with respect to the cleaning blade is between 0.2 and 1.4. In addition, it was found that in repeated image output, scratches on the photoreceptor surface and an increase in abrasion amount were effectively suppressed, and that the cleaning blade was not turned up under high temperature and high humidity.
[0019]
When the contact angle of the electrophotographic photosensitive member surface to pure water was less than 60 °, the scratches and abrasion amount on the photosensitive member surface were significantly increased, and the cleaning blade was turned up under high temperature and high humidity. On the other hand, when the contact angle of the electrophotographic photoreceptor surface with pure water was greater than 85 °, the amount of scratches and abrasion on the surface of the photoreceptor significantly increased, and toner slipped from the surface of the photoreceptor.
[0020]
Further, even when the contact angle of the electrophotographic photosensitive member surface with pure water is 60 ° or more and 85 ° or less, if the kinetic friction coefficient of the photosensitive member is larger than 1.4, the cleaning blade is turned up under high temperature and high humidity. . Further, even when the contact angle of the electrophotographic photosensitive member surface with pure water is 60 ° or more and 85 ° or less, if the kinetic friction coefficient of the photosensitive member is smaller than 0.2, toner slips through and cleaning is not established. Was.
[0021]
As the cleaning blade member used in the image forming method of the present invention, a member made of urethane rubber is preferably used because of its small size, light weight, low cost, abrasion resistance, and excellent cleaning characteristics. Further, the thickness of the cleaning blade member is preferably 0.5 to 10 mm.
[0022]
First, the amount of penetration λ of the cleaning blade 13a into the photosensitive drum 12a and the set angle ψ will be described with reference to FIG. The blade penetration amount λ is a virtual amount in which the tip of the blade 13a enters the photosensitive drum 12a without being deformed, and the blade setting angle ψ is a point at which the tip of the blade 13a intersects the photosensitive drum 12a. Is the angle between the tangent at the point and the blade 13a.
[0023]
Based on the above description, a method of measuring the blade contact pressure will be described with reference to FIG. First, in order to measure the linear pressure per unit cm, a blade 13a cut to a width of 1 cm is set on a blade base 57 movable in the direction of an arrow in the figure by a motor 56, and the blade 13a is set at about 20 ° to 25 °. The desired angle ψ is set to a desired angle and the load sensor 58 is contacted. Next, the blade table 57 is moved in the direction of the load sensor by the amount of penetration λ to be obtained, and the detected value of the load sensor 58 at that time is amplified by the amplifier 59 and read by the voltmeter 60. The load is measured by replacing the load per unit voltage determined in advance with the linear pressure per unit cm. The value measured in this manner is defined as the blade contact pressure.
[0024]
The higher the blade contact pressure, the better the toner cleaning performance. However, since the blade is in contact with the drum in the counter direction with respect to the drum rotation direction, adverse effects such as turning over the blade and chipping of the blade also occur.
[0025]
As the toner used in the electrophotographic apparatus of the present invention, a toner having a small particle diameter and a high circularity is used. By reducing the toner equivalent circle average diameter to preferably 2 to 10 μm, and more preferably 2 to 6 μm, the outline of an image, particularly, image formation and dot reproducibility can be improved. The average circularity is preferably 0.950 to 0.995, and the circularity standard deviation is less than 0.040. More preferably, the average circularity is 0.970 to 0.995, and the circularity standard deviation is 0. By setting it to be less than 035, the transferability of the toner having a small particle diameter, which has been difficult in the past, is greatly improved, and the developing ability for a low-potential latent image is also significantly improved.
[0026]
The toner may contain a wax component. Preferred wax components include petroleum waxes such as paraffin wax, microcrystalline wax and petrolactam and derivatives thereof, montan wax and derivatives thereof, and hydrocarbon waxes and their waxes by the Fischer-Tropsch method. Derivatives, polyolefin wax represented by polyethylene and its derivatives, carnauba wax, candelilla wax, etc., natural wax and its derivatives, etc., derivatives include block copolymers with oxides and vinyl monomers, including graft-modified products, Alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid or compounds thereof; acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, vegetable wax, animal wax, styrene mono As long as the melting temperature to over of 40 to 80 ° C., it is possible to use any.
[0027]
Among these, when polyolefin, hydrocarbon wax, petroleum wax, higher alcohol or higher ester by Fischer-Tropsch method is used, the effect of improving developability and transferability is further enhanced.
[0028]
The above-mentioned wax component is preferably used in an amount of 1 to 30 parts by mass based on 100 parts by mass of the binder resin.
[0029]
Examples of the binder resin include commonly used styrene- (meth) acrylic copolymers, polyester resins, epoxy resins, and styrene-butadiene copolymers. In a method of directly obtaining toner particles by a polymerization method, a monomer for forming them is used. Specifically, styrene; styrene monomers such as o- (m-, p-) methylstyrene and m- (p-) ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, (meth) ) Propyl acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( (Meth) acrylate monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; ene monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylamide It is preferably used. These can be used alone or in general so that the monomer exhibits a theoretical glass transition temperature (Tg) of 40 to 75 ° C as described in the published Polymer Handbook, 2nd edition III-P139-192 (manufactured by John Wiley & Sons). It is used by being appropriately mixed. If the theoretical glass transition temperature is lower than 40 ° C., problems tend to occur in terms of storage stability and durability stability of the toner, while if it exceeds 75 ° C., the fixing point of the toner increases. In particular, in the case of a color toner for forming a full-color image, the color mixture at the time of fixing each color toner is reduced, resulting in poor color reproducibility, and furthermore, the transparency of the OHP image is unfavorably reduced.
[0030]
In addition, a known charge control agent can be used for the toner, but a charge control agent which is particularly fast in charging speed and can stably maintain a constant charge amount is preferable. Further, in the case where a direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibitory property and having no water-soluble substance is preferable.
[0031]
Addition of an inorganic fine powder to the toner is a preferred embodiment for improving developability, transferability, charging stability, fluidity and durability. In addition, inorganic fine particles may be used, if necessary, for the purpose of hydrophobizing or controlling the chargeability, for example, a silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, a silane coupling agent, and a silane coupling agent having a functional group. It is also possible and preferable to use a treating agent such as an organic silicon compound and an organic titanium compound, or a combination of various treating agents.
[0032]
In the toner used in the present invention, further additives such as lubricant powders such as polytetrafluoroethylene powder, zinc stearate powder and polyvinylidene fluoride powder: cerium oxide powder within a range that does not substantially adversely affect the toner; Abrasives such as silicon carbide powder and strontium titanate powder: fluidity-imparting agents such as titanium oxide powder and aluminum oxide powder; anti-caking agents; and conductivity-imparting agents such as carbon black powder, zinc oxide powder and tin oxide powder In addition, a small amount of an organic fine particle and an inorganic fine particle having the opposite polarity can be used as a developing property improver.
[0033]
The developing method in the electrophotographic apparatus of the present invention may be any of a regular developing method represented by a copying machine and a reversal developing method represented by a laser printer. The developing methods include a two-component magnetic brush developing method and a two-component developing method. Method, a magnetic one-component developing method, or a non-magnetic one-component developing method.
[0034]
As the electrophotographic photoreceptor of the present invention, a laminated photoreceptor obtained by sequentially laminating a charge generation layer and a charge transport layer on a conductive substrate is used.
[0035]
Between the conductive substrate and the photosensitive layer, there is a coating of structural defects on the substrate, improved adhesion between the photosensitive layer and the substrate, protection against electrical breakdown of the photosensitive layer, improvement in chargeability, charge from the substrate to the photoconductive layer. A conductive layer may be provided for improving the injection property or the like.
[0036]
The conductive substrate used in the present invention is only required to have conductivity, such as metals such as aluminum and stainless steel, alloys such as aluminum alloys and indium oxide-tin oxide alloys, and plastics having a coating layer of these metals and alloys. A cylindrical cylinder or film of paper or plastic impregnated with conductive particles, plastic having a conductive polymer, or the like is used.
[0037]
The conductive particles (fillers) dispersed in the conductive layer include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, indium oxide doped with tin, tin oxide and zirconium oxide doped with antimony and tantalum, and the like. Such as conductive metal oxides, metal sulfides such as barium sulfate, carbon black or particles containing these, among which tin oxide, titanium oxide, barium sulfate and antimony oxide are preferred. The average particle size is preferably from 0.01 to 0.5 μm, particularly preferably from 0.02 to 0.3 μm. The resin in which the conductive fine powder is dispersed can be appropriately selected from those which are not eluted by the solvent of the barrier layer or the coating material for the photosensitive layer directly applied on the conductive layer. In general, when the average particle size of the filler is small, dispersion becomes difficult and reagglomeration is likely to occur, but a filler having excellent dispersibility is used. The content of the filler is preferably from 1.0 to 90% by mass, and particularly preferably from 5.0 to 80% by mass, based on the conductive layer.
[0038]
As the resin used for the conductive layer, for example, phenol resin, polyurethane, polyamide, polyimide, polyamide imide, polyamic acid, polyvinyl acetal, epoxy resin, acrylic resin, melamine resin, polyester, and the like are preferable. These resins may be used alone or in combination of two or more. These resins have good adhesiveness to the support, improve the dispersibility of the filler, and have good solvent resistance after film formation. Among the above resins, a phenol resin and a polyurethane are particularly preferable.
[0039]
In order to improve the dispersibility of the filler, the surface of the filler may be treated with a treating agent such as a coupling agent (such as a silane coupling agent or a titanium coupling agent) or silicone oil. Further, the treatment agent may be contained in a binder of the conductive layer.
[0040]
The thickness of the conductive layer is preferably from 0.1 to 30 μm, particularly preferably from 0.5 to 20 μm. The volume resistivity of the conductive layer is 10 ^Thirteen Ω · cm or less, preferably 10 Ω · cm or more ¹² Ω · cm or less is preferable. A leveling agent may be added to the conductive layer in order to enhance the surface properties of the conductive layer.
[0041]
Depending on the kind of the material of the photosensitive layer, free carriers may be injected from the conductive layer into the photosensitive layer, which lowers the charging ability of the photosensitive member and greatly affects image characteristics. In such a case, if necessary, an intermediate layer (for example, an appropriate resin thin film) having an electric barrier property is provided between the conductive layer and the photosensitive layer to effectively suppress the injection of the free carrier. Can be.
[0042]
As the intermediate layer, for example, polyvinyl alcohol, polyvinyl methyl ether, polyacrylic acids, methyl cellulose, ethyl cellulose, polyglutamic acid, casein, water-soluble resin such as starch, polyamide, polyimide, polyamide imide, polyamic acid, melamine resin, epoxy resin, Resins such as polyurethane and polyglutamic acid ester can be used. In particular, polyamide is preferred as the intermediate layer in terms of coating properties, adhesion, solvent resistance, electrical barrier properties, resistance, and the like. As the polyamide, low crystalline or non-crystalline copolymerized nylon which can be applied in a solution state is suitable. The thickness of the intermediate layer is preferably from 0.1 to 2.0 μm.
[0043]
Examples of the charge generating material used in the present invention include selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine, anthantrone, dibenzpyrene quinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone, and asymmetric quinocyanine pigments. Is mentioned. Examples of the phthalocyanine include metal phthalocyanines such as aluminum chlorophthalocyanine, chloroindium phthalocyanine, oxyvanadyl phthalocyanine, hydroxygallium phthalocyanine, chlorogallium phthalocyanine, magnesium phthalocyanine, and oxytitanium phthalocyanine, and metal-free phthalocyanines. Phthalocyanine greatly differs in sensitivity and other electrophotographic characteristics depending on its crystal structure, and its structure can be confirmed by X-rays or the like.
[0044]
Various resins can be used as the binder resin of the charge generation layer, and specifically, for example, polycarbonate resin, polyester resin, polyarylate resin, butyral resin, polystyrene resin, polyvinyl acetal resin, diallyl phthalate resin, acrylic resin, methacrylic resin , Vinyl acetate resin, phenolic resin, silicone resin, polysulfone resin, styrene-butadiene copolymer resin, alkyd resin, epoxy resin, urea resin and vinyl chloride-vinyl acetate copolymer resin. However, the present invention is not limited to this.
[0045]
Further, as the dispersing solvent, alcohols, sulfoxides, ketones, ethers, esters, aliphatic halogenated hydrocarbons, aromatic compounds and the like can be used.
[0046]
The charge generation layer is made of a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill or a liquid collision type high-speed disperser together with a charge generation material material, a binder resin and a solvent in an amount of 0.3 to 4.0 times the amount. And the dispersion is applied and dried to form a dispersion. The thickness of the charge generation layer is preferably 5 μm or less, more preferably 0.01 to 0.4 μm.
[0047]
Various sensitizers, antioxidants, ultraviolet absorbers, plasticizers or known charge generation materials can be added to the charge generation layer as needed.
[0048]
The charge transport layer in the present invention is formed by applying and drying a paint in which a charge transport material and a binder resin are dissolved in a solvent. Examples of the charge transport material used include a triarylamine compound, a hydrazone compound, a stilbene compound, a pyrazoline compound, an oxazole compound, a triallylmethane compound, and a thiazole compound.
[0049]
Specific examples of the binder resin include acrylic resins such as polymethyl methacrylate and styrene-acryl copolymer; polystyrene, low molecular weight polypropylene, styrene-butadiene rubber, ethylene-vinyl acetate copolymer, vinyl chloride, and acetic acid. Vinyl and their copolymers; petroleum resin, saturated alkyl polyester resin; aromatic polyester resin such as polyethylene terephthalate resin, polybutylene terephthalate resin and polyarylate resin; polyacetal, polycarbonate, polyether sulfone, polysulfone, polyphenylene sulfide and polyether Ether ketone and the like can be mentioned. The contact angle of the surface layer of the photoreceptor with respect to pure water in the present invention can be controlled by the type of the binder resin and the charge transport agent of the charge transport layer, and it is considered that the contact angle is particularly caused by the structure of the binder resin. The present invention is characterized in that the contact angle of the surface layer with pure water is not less than 60 ° and not more than 85 °, and the physical property value is important. Examples of the material exhibiting the physical property in this range include polyarylate resin and the like. And the structure represented by the formula (1) is particularly preferable. Furthermore, the polyarylate resin represented by the formula (2) has a very small contact angle with pure water, and is more preferable.
[0050]
Embedded image

[0051]
Where R ₁ And R ₂ Are each independently a halogen atom, an alkyl group which may be substituted, an aryl group or an alkylene group, a and b are each independently an integer of 0 to 4, X is a single bond, -O-, -S -Or -CR ₃ R ₄ -. R ₃ And R ₄ Is a hydrogen atom, a halogen atom, an alkyl group, an aryl group or R ₅ And R ₆ Is an alkylidene group formed by bonding.
[0052]
Embedded image

[0053]
Where R ₅ And R ₆ Is each independently a halogen atom, an alkyl group which may be substituted, an aryl group or an alkylene group, and c and d are each independently an integer of 0 to 4.
[0054]
If necessary, an antioxidant, an ultraviolet absorber, a plasticizer, or a known charge transport material may be added to the charge transport layer. Next, FIG. 3 shows a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.
[0055]
In FIG. 3, reference numeral 21 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around an axis 22 in a direction indicated by an arrow at a predetermined peripheral speed (process speed). The electrophotographic photosensitive member 21 receives a uniform charge of a predetermined positive or negative potential on the peripheral surface thereof by the primary charging means 23 during the rotation process, and then receives light from exposure means (not shown) such as slit exposure or laser beam scanning exposure. The exposure light 24 is intensity-modulated in accordance with a time-series electric digital image signal of target image information to be output. In this way, an electrostatic latent image corresponding to the target image information is sequentially formed on the peripheral surface of the electrophotographic photosensitive member 21.
[0056]
The formed electrostatic latent image is then visualized as a transferable particle image (toner image) with charged particles (toner) in the developing unit 5 by regular development or reversal development, and is electrophotographic from a paper feeding unit (not shown). The toner image formed and carried on the surface of the electrophotographic photosensitive member 21 is transferred onto the transfer material 27 taken out and fed between the photosensitive member 21 and the transfer means 26 in synchronization with the rotation of the electrophotographic photosensitive member 21. The image is sequentially transferred by the transfer unit 26. At this time, a bias voltage having a polarity opposite to the charge retained in the toner is applied to the transfer unit from a bias power supply (not shown).
[0057]
The transfer material 27 to which the toner image has been transferred is separated from the surface of the electrophotographic photosensitive member, conveyed to an image fixing unit 28, and subjected to a fixing process of the toner image, thereby being printed outside the apparatus as an image formed product (print, copy). Be out.
[0058]
After the transfer of the toner image, the surface of the electrophotographic photoreceptor 21 is cleaned by a cleaning unit 29 to remove extraneous matters such as untransferred toner. In recent years, a cleaner-less system has been studied, and transfer residual toner can be directly collected by a developing device or the like. Further, after being subjected to static elimination processing by pre-exposure light 30 from a pre-exposure unit (not shown), it is repeatedly used for image formation. When the primary charging unit 23 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required.
[0059]
In the present invention, among the above-mentioned components such as the electrophotographic photoreceptor 21, the primary charging means 23, the developing means 25, and the cleaning means 29, a plurality of components are housed in a container and integrally combined as a process cartridge. The process cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 23, the developing unit 25, and the cleaning unit 29 is integrally supported together with the electrophotographic photosensitive member 21 to form a cartridge, and is attached to and detached from the apparatus main body by using a guide unit 32 such as a rail of the apparatus main body. A flexible process cartridge 31 can be provided.
[0060]
When the electrophotographic apparatus is a copying machine or a printer, the exposure light 24 is light reflected from or transmitted from the original, or the original is read by a sensor, converted into a signal, and scanned by a laser beam performed in accordance with the signal. , Light emitted by driving an LED array or driving a liquid crystal shutter array.
[0061]
The electrophotographic photoreceptor of the present invention can be widely used not only for electrophotographic copying machines but also for electrophotographic applications such as laser beam printers, CRT printers, LED printers, faxes, liquid crystal printers, and laser plate making. It is.
[0062]
【Example】
Hereinafter, the present invention will be described in more detail with reference to specific examples. However, embodiments of the present invention are not limited to these. In the examples, “parts” means “parts by mass”.
[0063]
<Production Example 1 of Photoconductor>
An aluminum cylinder (JISA 3003 aluminum alloy) having a length of 260.5 mm, a diameter of 30 mm, a thickness of a cylinder portion of 0.7 mm, a maximum surface roughness of 5.0 μm, and an average surface roughness of 1.0 μm was prepared.
[0064]
60 parts of powder made of barium sulfate particles having a tin oxide coating layer (Pastran PC1, manufactured by Mitsui Mining & Smelting Co., Ltd.), 60 parts of titanium oxide (TITANIX JR, manufactured by Teica Co., Ltd.), resole type phenolic resin (pheno) 70 parts of Light J-325, manufactured by Dainippon Ink and Chemicals, Inc., 70% solid content, 10 parts of silicone oil (SH28PA, manufactured by Toray Silicone Co., Ltd.), 10 parts of silicone resin (Tospearl 120, manufactured by Toshiba Silicone Co., Ltd.) ) A solution consisting of 10 parts, 60 parts of 2-methoxy-1-propanol and 60 parts of methanol was dispersed in a ball mill for about 20 hours.
[0065]
The conductive layer dispersion prepared in this manner was applied onto the above-mentioned aluminum cylinder by an immersion method, and was heated and cured at 140 ° C. for 30 minutes to form a resin layer having a thickness of 12 μm.
[0066]
Next, 10 parts of a copolymerized nylon resin (trade name: Amilan CM8000, manufactured by Toray Industries, Inc.) and 30 parts of methoxymethylated 6 nylon resin (trade name: Toresin EF-30T, manufactured by Teikoku Chemical Co., Ltd.) were mixed with 400 parts of methanol. A solution dissolved in a mixed solution of 200 parts by weight / n-butanol was dip-coated on the resin layer, and dried by heating at 90 ° C. for 10 minutes to form a barrier layer having a thickness of 0.62 μm.
[0067]
Next, a mixed solution consisting of 8.5 parts of a gallium phthalocyanine pigment represented by the following formula (3), 5 parts of a polyvinyl butyral resin (trade name: Esrec BX-1, manufactured by Sekisui Chemical Co., Ltd.), and 60 parts of cyclohexanone was φ1 mm glass beads. Was dispersed in a sand mill using for 3 hours, and 100 parts of ethyl acetate was added to prepare a coating liquid for a charge generation layer. This coating solution was applied on the above-prepared intermediate layer by a bar coating method, and dried by heating at 90 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.08 μm.
[0068]
Embedded image

In the formula, Xs each independently represent a Cl or Br group. m, n, p and k each independently represent an integer of 0-4.
[0069]
Next, the following materials were dissolved and adjusted to prepare a coating liquid for a charge transport layer.
[0070]
40 parts of a charge transporting material represented by the following formula (4)
50 parts of polyarylate represented by the following formula (5)
(Viscosity average molecular weight 105000)
Chlorobenzene 350 parts
[0071]
Embedded image

[0072]
Embedded image

[0073]
The coating liquid for a charge transport layer was dip-coated on the charge generation layer, and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 25 μm.
[0074]
At this time, the contact angle of the surface layer with water was measured as follows, and was 78 °.
[0075]
<Method of measuring contact angle>
The contact angle was measured using pure water at normal temperature and normal humidity (25 ° C./50% RH), and a contact angle type CA-DS manufactured by Kyowa Interface Science Co., Ltd. was used as an apparatus. The contact angle was an average value of five points on the surface of the photoreceptor and was measured within one minute after the attachment of the water droplet.
[0076]
Further, the dynamic friction coefficient of the surface layer was measured as follows, and was 1.2.
[0077]
<Method of measuring dynamic friction coefficient>
The dynamic friction coefficient (μ) of the photoreceptor surface was measured at room temperature and normal humidity (25 ° C./50% RH) by using a cleaning blade fixing device shown in a schematic sectional view of FIG. 4 with a surface test device (model HEIDON manufactured by HEIDON). -14)｝ was used. In this apparatus, the blade 7 is pressed against the electrophotographic photosensitive member 6 with a constant load (g), and the force (g) applied when the blade 7 is moving in parallel with the surface of the photosensitive member is measured. The coefficient of kinetic friction is obtained from [force (g) applied to photoconductor] / [load (g) applied to blade] when the blade is moving. As a blade to be used, a urethane blade (rubber hardness: 67 °) manufactured by Hokushin Kogyo Co., Ltd. was cut into 5 mm × 30 mm × 2 mm, and measured at a load of 10 g in the with direction at an angle of 20 °.
[0078]
<Production Example 2 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0079]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0080]
25 parts of the charge transport material of the formula (4)
50 parts of polyarylate of the formula (5)
Comb type silicone 0.75 parts
(Alon GS101CP, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
Chlorobenzene 300 parts
5 parts of a silicone-modified polycarbonate of the following formula (6)
(Viscosity average molecular weight 40,000)
[0081]
Embedded image

[0082]
The coating liquid for a charge transport layer was applied onto the charge generation layer by dip coating, and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 85 °. The dynamic friction coefficient of the surface layer was 0.5.
[0083]
<Production Example 3 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0084]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0085]
25 parts of the charge transport material of the formula (3)
50 parts of polyarylate of the formula (5)
Chlorobenzene 300 parts
5 parts of a silicone-modified polycarbonate of the following formula (7)
(Viscosity average molecular weight 40,000)
[0086]
Embedded image

[0087]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 85 °. The dynamic friction coefficient of the surface layer was 1.4.
[0088]
<Production Example 4 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0089]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0090]
60 parts of the charge transport material of the formula (4)
50 parts of polyarylate of the formula (5)
Comb type silicone 0.75 parts
(Alon GS101CP, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
Chlorobenzene 400 parts
[0091]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 60 °. The dynamic friction coefficient of the surface layer was 0.5.
[0092]
<Production Example 5 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0093]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0094]
54 parts of the charge transport material of the formula (3)
6 parts of a charge transport material of the following formula (8)
50 parts of polyarylate of the formula (5)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
Chlorobenzene 400 parts
[0095]
Embedded image

[0096]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 60 °. The dynamic friction coefficient of the surface layer was 0.5.
[0097]
<Example 6 of manufacturing photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0098]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0099]
60 parts of the charge transport material of the following formula (9)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
Comb type silicone 0.75 parts
(Alon GS101CP, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
Chlorobenzene 400 parts
[0100]
Embedded image

[0101]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 75 °. Further, the dynamic friction coefficient of the surface layer was 0.4.
[0102]
<Production Example 7 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0103]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0104]
54 parts of the charge transport material of the formula (9)
6 parts of the charge transport material of the formula (8)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
Chlorobenzene 400 parts
[0105]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 75 °. The dynamic friction coefficient of the surface layer was 1.4.
[0106]
<Production Example 8 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0107]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0108]
40 parts of the charge transport material of the formula (9)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
Chlorobenzene 350 parts
[0109]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 95 °. The dynamic friction coefficient of the surface layer was 1.0.
[0110]
<Production Example 9 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0111]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0112]
75 parts of the charge transport material of the formula (9)
45 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
Chlorobenzene 400 parts
[0113]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 57 °. The dynamic friction coefficient of the surface layer was 1.0.
[0114]
<Production Example 10 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0115]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0116]
40 parts of the charge transport material of the formula (9)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
0.95 parts of comb silicone
(Alon GS101CP, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
Chlorobenzene 350 parts
[0117]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 95 °. Further, the dynamic friction coefficient of the surface layer was 0.4.
[0118]
<Production Example 11 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0119]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0120]
36 parts of the charge transport material of the formula (9)
4 parts of the charge transport material of the formula (8)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
Chlorobenzene 350 parts
[0121]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 95 °. The dynamic friction coefficient of the surface layer was 1.4.
[0122]
<Photoconductor Production Example 12>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0123]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0124]
40 parts of the charge transport material of the formula (9)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
0.95 parts of comb silicone
(Alon GS101CP, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
Chlorobenzene 350 parts
[0125]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 55 °. Further, the dynamic friction coefficient of the surface layer was 0.4.
[0126]
<Production Example 13 of Photoconductor>
The charge generation layer was provided in the same manner as in Photoconductor Production Example 1.
[0127]
Next, a coating liquid for a charge transport layer was prepared using the following materials.
[0128]
70 parts of the charge transport material of the formula (9)
5 parts of the charge transport material of the formula (8)
50 parts of polycarbonate
(Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.)
5 parts of a silicone-modified polycarbonate of the formula (7)
(Viscosity average molecular weight 40,000)
Chlorobenzene 400 parts
[0129]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm. At this time, the contact angle of the surface layer with water was 55 °. The dynamic friction coefficient of the surface layer was 1.5.
[0130]
<Production Example 14 of Photoconductor>
In the same manner as in Photoconductor Production Example 1, an intermediate layer was provided.
[0131]
Next, a mixed solution consisting of 7.5 parts of an azo pigment represented by the following formula (10), 5 parts of a polyvinyl butyral resin (trade name: Esrec BX-1, manufactured by Sekisui Chemical Co., Ltd.), and 60 parts of THF was mixed with φ1 mm glass beads. After dispersing for 3 hours by using a sand mill, 100 parts of cyclohexanone was added to prepare a coating liquid for a charge generation layer. This coating solution was applied on the above-prepared intermediate layer by a bar coating method, and dried by heating at 90 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.08 μm.
[0132]
Embedded image

In the formula, Xs each independently represent a Cl or Br group. m, n, p and k each independently represent an integer of 0-4.
[0133]
Next, the following materials were dissolved and adjusted to prepare a coating liquid for a charge transport layer.
[0134]
36 parts of the charge transporting material represented by the formula (4)
4 parts of the charge transporting material represented by the formula (8)
50 parts of polyarylate represented by the following formula (11)
(Viscosity average molecular weight 130000)
Chlorobenzene 350 parts
[0135]
Embedded image

[0136]
This coating liquid for a charge transport layer was dip-coated on the charge generation layer, and dried by heating at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 30 μm. At this time, the contact angle of the surface layer with water was measured as follows, and was 78 °.
[0137]
<Toner Production Example 1>
600 g of ion-exchanged water and 0.1 mol / l-Na were placed in a 2-liter 4-neck flask equipped with a high-speed stirrer TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). ₃ PO ₄ 500 g of the aqueous solution was charged, the rotation speed was adjusted to 14000 rpm, and the mixture was heated to 65 ° C. Here, 1.0 mol / liter-CaCl ₂ 70 parts of an aqueous solution is gradually added, and a fine hardly water-soluble dispersion stabilizer Ca is added. ₃ (PO ₄ ) ₂ The aqueous dispersion medium containing was prepared.
[0138]
On the other hand, as a dispersoid,
Styrene 78 parts
22 parts of n-butyl acrylate
0.2 parts of divinylbenzene
Carbon black (BET specific surface area 50m ² / G) 5 parts
Unsaturated polyester (condensation polymer of epoxidized bisphenol A with fumaric acid,
(Peak molecular weight = 7000) 4 parts
Chlor compound of di-tert-butylsalicylic acid 2 parts
Ester wax (mp = 62 ° C) 10 parts
[0139]
After dispersing the above mixture for 3 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.), 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) was added to prepare a polymerizable monomer composition. did.
[0140]
Next, the polymerizable monomer composition was charged into the aqueous dispersion medium, and N.sub.2 at an internal temperature of 65.degree. ₂ Under an atmosphere, the mixture was stirred for 15 minutes while maintaining the rotation speed of the high-speed stirrer at 12,000 rpm to granulate the polymerizable monomer composition. Then, the polymerization was completed by maintaining the same temperature for 10 hours while stirring at 50 rpm, replacing the stirrer with a propeller stirring blade.
[0141]
After completion of the polymerization, the suspension was cooled, and then dilute hydrochloric acid was added to remove the dispersion stabilizer. Further, after repeating water washing several times, the toner particles are subjected to sphering treatment and drying treatment for 10 hours while stirring in hot air using a fluidized bed dryer (manufactured by Okawara Seisakusho Co., Ltd.), and polymer particles (A) are obtained. Obtained. The polymer particles (A) had a circle-equivalent number average diameter of 4.1 μm.
[0142]
100 parts of the above polymer particles (A) and hydrophobic oil-treated silica fine particles (BET: 200 m ² / G) 2 parts were dry-mixed with a Henschel mixer to prepare toner (A).
[0143]
<Toner Production Example 2>
A toner was manufactured in the same manner as in Toner Manufacturing Example 1, except that the number of revolutions of the high-speed stirrer was changed to 18000 rpm and the processing time of the fluidized bed dryer was changed to 20 hours. The circle-equivalent number average diameter of this toner was 2.3 μm.
[0144]
<Toner Production Example 3>
A toner was produced in the same manner as in Toner Production Example 1, except that the number of revolutions of the high-speed stirrer was changed to 8000 rpm, and the processing time of the fluidized bed dryer was changed to 5 hours. The toner had a circle-equivalent number average diameter of 7.0 μm.
[0145]
<Toner Production Example 4>
Styrene-n-butyl acrylate-divinylbenzene resin 100 parts
(Peak molecular weight = 15000, Mw / Mn = 2.4, Tg = 50 ° C.)
4 parts of unsaturated polyester used in Production Example 1 of toner
5 parts of carbon black used in toner production example 1
Negative charge control agent (monoazo-based iron complex) 2 parts
10 parts of ester wax used in toner production example 1
[0146]
The above mixture is melt-kneaded with a twin-screw extruder, the cooled kneaded material is roughly pulverized with a hammer mill, the ground material is finely pulverized with a jet mill, and the obtained finely pulverized product is mixed with a commercially available calcium phosphate fine powder by Henschel. After mixing with a mixer, the obtained mixed powder was put into a container containing water, further dispersed in water using a homonixer, and the temperature of the water was gradually increased, followed by heat treatment at a temperature of 60 ° C for 2 hours. Thereafter, diluted hydrochloric acid was added to the container to sufficiently dissolve the calcium phosphate on the surface of the finely pulverized product particles. After filtering, the resultant was washed and dried, and then passed through a 400-mesh sieve to remove aggregates, and then classified to obtain a toner (D). A toner (D) was prepared in the same manner as in Toner Production Example 1. The circle-equivalent number average diameter of this toner was 8.2 μm.
[0147]
<Toner Production Example 5>
As a dispersant,
80 parts of ethylene
20 parts of 2-ethylhexyl acrylate
0.3 parts of divinylbenzene
Carbon black (BET specific surface area = 50m ² / G) 7 parts
Spiron Black TRH (Hodogaya Chemical Industry Co., Ltd.) 1 copy
Polypropylene (Viscole 550P, manufactured by Sanyo Chemical Co., Ltd.) 10 parts
2,2'-azobis (2,4-dimethylvaleronitrile) 3 parts
Was thoroughly mixed with a sand mill to obtain a heavy synthetic composition.
[0148]
This heavy-synthetic composition was added to water containing 1 part of tricalcium phosphate and 0.01 part of sodium dodecylbenzenesulfonate as a dispersion stabilizer. ₂ Under an atmosphere, the mixture was dispersed with a high-speed stirrer to obtain a suspension. Thereafter, the suspension was placed in a three-necked flask equipped with a stirrer, heated at 70 ° C. for 10 hours with stirring, and polymerized. Thereafter, tricalcium phosphate was removed with an aqueous hydrochloric acid solution, washed with water, and dried. Thus, a toner was obtained. To 100 parts of this polymerized toner, 0.3 part of hydrophobic silica fine powder (trade name: Aerosil R-972, manufactured by Aerosil Co., Ltd.) was added and mixed to obtain a toner (E). This toner had a circle-equivalent number average diameter of 11.2 μm.
[0149]
(Example 1)
An embodiment of the electrophotographic apparatus of the present invention will be described. As an electrophotographic apparatus, LBP manufactured by Hewlett-Packard (trade name: Laser Jet 4000, process speed: 94.2 mm / sec) was used.
[0150]
The contact pressure of the cleaning blade against the photoreceptor was set to 70 g / cm, and the electrophotographic photoreceptor used was the one shown in Photoreceptor Production Example 1.
[0151]
The developing device was modified as follows. A medium resistance rubber roller made of silicone rubber in which carbon black was dispersed and whose resistance was adjusted instead of an aluminum sleeve containing a magnet for toner supply resistance was used as a toner carrier, and was brought into contact with the electrophotographic photosensitive member. The moving direction and the rotation speed of the surface of the toner carrier are the same in the contact portion with the electrophotographic photosensitive member, and the toner carrier is driven to be 150% of the rotational speed of the electrophotographic photosensitive member. As means for applying the toner on the toner carrier, the application roller was brought into contact with the toner carrier, and rotated in a direction opposite to the toner carrier to apply the toner. Further, the toner was replaced with that shown in Toner Production Example 1.
[0152]
Table 1 shows the configuration of the main body, the electrophotographic photosensitive member, and the toner.
[0153]
This LBP was placed in an environment of 30 ° C./80% RH, and 10,000 copies were continuously copied to evaluate the image. As a voltage applied to the photoreceptor, a DC bias of -620 V is applied, and the surface of the photoreceptor sample is charged by superimposing an AC bias having a frequency of 1600 Hz and 1300 µA. And Subsequently, laser light was applied to set the bright portion potential Vl to -140V. The amount of laser light is 0.3μJ / cm ² And
[0154]
As a result of the durability, no cleaning failure occurred, and no turning of the blade occurred. The abrasion loss of the photoreceptor due to the durability of 10,000 sheets was 1.5 μm, and the image density and dot reproducibility before and after the durability were good. The image density was confirmed by outputting a solid image. The dot reproducibility was confirmed by outputting an isolated dot image as shown in FIG. 5 and using a loupe. Table 2 shows the results.
[0155]
(Examples 2 to 11)
The main body, the cleaning blade contact pressure, the electrophotographic photosensitive member, and the toner configuration were set as shown in Table 1, and the evaluation was performed in the same manner as in Example 1. Table 2 shows the results.
[0156]
(Comparative Examples 1 to 12)
The main body, the cleaning blade contact pressure, the electrophotographic photosensitive member, and the toner configuration were set as shown in Table 1, and the evaluation was performed in the same manner as in Example 1. Table 2 shows the results.
[0157]
[Table 1]

[0158]
[Table 2]

[0159]
【The invention's effect】
As described above, according to the present invention, in an electrophotographic apparatus using a small-diameter toner, without using a lubricant in or on a photosensitive layer, the cleaning property is excellent, and image defects and characteristic deterioration at the time of repeated image output are caused. In addition, it has become possible to provide an electrophotographic apparatus and a process cartridge capable of supplying a high-definition image with high image quality.
[Brief description of the drawings]
FIG. 1 is a cross-sectional configuration diagram of an electrophotographic photosensitive member and a cleaning blade.
FIG. 2 is a diagram illustrating an example of a method of measuring a blade contact pressure.
FIG. 3 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member according to the present invention.
FIG. 4 is a schematic sectional view of a cleaning blade fixing device for measuring a dynamic friction coefficient of the surface of the electrophotographic photosensitive member.
FIG. 5 is a diagram showing an output example of an isolated dot image (1 square = 42 μm × 42 μm).
[Explanation of symbols]
1 prop
2 Holder support arm
3 Upper holder
4 Lower holder
5 fixed screws
6 samples
7 Urethane rubber blade
12a Photoreceptor drum
13a Cleaning blade
21 Electrophotographic photoreceptor
22 axes
23 Charging means
24 Exposure light
25 Developing means
26 transfer means
27 Transfer material
28 Fixing means
29 Cleaning means
30 Pre-exposure light
31 process cartridge
32 Guide
56 drive motor
57 Movable blade base
58 Load sensor
59 amplifier
60 Electrometer

Claims (5)

In an electrophotographic apparatus having a cleaning means in which a contact pressure of a cleaning blade against an electrophotographic photosensitive member is 60 g / cm or more, the electrophotographic photosensitive member is an organic photoconductive photosensitive member, and a contact angle of the surface with pure water is reduced. An electrophotographic apparatus characterized in that the angle is 60 ° or more and 85 ° or less and the coefficient of dynamic friction with respect to the cleaning blade is 0.2 or more and 1.4 or less. 2. The electrophotographic apparatus according to claim 1, wherein the electrophotographic photosensitive member has a dynamic friction coefficient of 0.5 or more and 1.2 or less. 3. The electrophotographic apparatus according to claim 1, wherein the surface layer of the electrophotographic photosensitive member contains a polyarylate having a structural unit represented by the following formula (1).

(Wherein, R ₁ and R ₂ are each independently a halogen atom, an alkyl group which may be substituted, an aryl group or an alkylene group, a and b are each independently an integer of 0 to 4, and X is single bond, -O -, - S-, or _-CR 3 _{R 4} - is .R ₃ and _{R 4} are formed by a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or _{R 3} and _{R 4} are bonded Alkylidene group) The electrophotographic apparatus according to any one of claims 1 to 3, wherein the surface layer of the electrophotographic photosensitive member contains a polyarylate having a structural unit represented by the following formula (2).

(In the formula, R ₅ and R ₆ are each independently a halogen atom, an optionally substituted alkyl group, an aryl group or an alkylene group, and c and d are each independently an integer of 0 to 4.) 5. The electrophotographic apparatus according to claim 1, wherein charging means for charging the electrophotographic photosensitive member, developing means for developing the electrophotographic photosensitive member on which the electrostatic latent image is formed with toner, and after the transfer step. A process cartridge which integrally supports at least one unit selected from the group consisting of a cleaning unit for recovering toner remaining on the electrophotographic photosensitive member, and is detachable from an electrophotographic apparatus main body.

Images