JP4067417B2 - Electrophotographic photoreceptor - Google Patents

Description

【００６１】
【表２】

【００６２】
＜電荷発生層用分散液の作製＞
＜下引き層用分散液の作製＞
酸化チタン（石原産業（株）製：商品名ＴＴＯ５５Ｎ（平均一次粒子径約４０ｎｍ））にメチルジメトキシシランを３重量％処理したチタニアを、ボールミルによりメタノール／ｎ−プロパノール＝７／３の混合溶媒中で分散し、その酸化チタンスラリーに、下記構造式（１）の共重合ポリアミド溶解液を混合し、更に超音波分散処理を行い、溶媒組成が、メタノール／ｎ−プロパノール＝７／３で、酸化チタン／ポリアミド＝３／１で、固形分濃度１６重量％の分散液を調整し、下引き層用分散液を作製した。
【００６３】
【化１】

【００６４】
ＣｕＫα線によるＸ線回折においてブラック角（２θ±０．２）９．３°、１０．６°、１３．２°、１５．１°、１５．７°、１６．１°、２０．８°、２３．３°、２６．３°、２７．１°に強い回折ピークを示すオキシチタニウムフタロシアニン１０部を、１，２−ジメトキシエタン１５０部に加え、サンドグラインドミルにて粉砕分散処理を行い、顔料分散液を作製した。
【００６５】
ポリビニルブチラール（電気化学工業（株）製、商品名デンカブチラール＃６０００Ｃ）５部を１，２−ジメトキシエタン９５部に溶解し、固形分濃度５％のバインダー溶液１を作製した。
フェノキシ樹脂（ユニオンカーバイド社製、商品名ＰＫＨＨ）５部を１，２−ジメトキシエタン９５部に溶解し、固形分濃度５％のバインダー溶液２を作製した。
先に作製した顔料分散液１６０部に、バインダー溶液１を５０部、バインダー溶液２を５０部、適量の１，２−ジメトキシエタンと、適量の４−メトキシ−４−メチルペンタノン−２を加え固形分濃度４．０％、１，２−ジメトキシエタン：４−メトキシ−４−メチルペンタノン−２＝９：１の電荷発生層用分散液αを調製した。
【００６６】
ＣｕＫα線によるＸ線回折においてブラッグ角（２θ±０．２）２７．３゜に最大回折ピークを示すオキシチタニウムフタロシアニン１０部を、１，２−ジメトキシエタン１５０部に加え、サンドグラインドミルにて粉砕分散処理を行い、顔料分散液を作製した。
この顔料分散液１６０部に、ポリビニルブチラール（電気化学工業（株）製、商品名デンカブチラール＃６０００Ｃ）５部を１，２−ジメトキシエタン９５部に溶解した、固形分濃度５％のバインダー溶液１００部と、適量の１，２−ジメトキシエタン、適量の４−メトキシ−４−メチルペンタノン−２を加え、固形分濃度４．０％、１，２−ジメトキシエタン：４−メトキシ−４−メチルペンタノン−２＝９：１の電荷発生層用分散液β１を作製した。
ＣｕＫα線によるＸ線回折においてブラッグ角（２θ±０．２）９．３°、１０．６°、１３．２°、１５．１°、１５．７°、１６．１°、２０．８°、２３．３°、２６．３°、２７．１°に強い回折ピークを示すオキシチタニウムフタロシアニン１０部を、１，２−ジメトキシエタン１５０部に加え、サンドグラインドミルにて粉砕分散処理を行い、顔料分散液を作製した。
この顔料分散液１６０部に、ポリビニルブチラール（電気化学工業（株）製、商品名デンカブチラール＃６０００Ｃ）５部を１，２−ジメトキシエタン９５部に溶解した、固形分濃度５％のバインダー溶液１００部と、適量の１，２−ジメトキシエタン、適量の４−メトキシ−４−メチルペンタノン−２を加え、固形分濃度４．０％、１，２−ジメトキシエタン：４−メトキシ−４−メチルペンタノン−２＝９：１の電荷発生層用分散液β２を作製した。
電荷発生層用分散液β１と電荷発生層用分散液β２を８：２の割合で混合し、電荷発生層用分散液βを調製した。
【００６７】
＜感光体の作製＞
実施例１
表面が鏡面仕上げされた外径３０ｍｍ、長さ２８５ｍｍ、肉厚１．０ｍｍのアルミニウム合金よりなるシリンダーの表面に、陽極酸化処理を行い、その後酢酸ニッケルを主成分とする封孔剤によって封孔処理を行うことにより、約６μｍの陽極酸化被膜（アルマイト被膜）を形成した。このシリンダーを先に作製した電荷発生層用分散液αに浸漬塗布し、その乾燥後の重量が０．３ｇ／ｍ²（膜厚約０．３μｍ）となるように電荷発生層を形成した。
次に、この電荷発生層を形成したシリンダーを、下記構造式（２）に示す電荷輸送性化合物５０部と、電荷輸送層用バインダー樹脂として製造例１で作製したポリカーボネート樹脂（粘度平均分子量約３０，９００、Ｍｗ／Ｍｎ＝１．３４、Ｍｖ／Ｍｎ′＝１．１５）１００部、シリコーンオイル（信越化学社製、商品名ＫＦ９６）０．０５部をテトラヒドロフラン：１，４−ジオキサン＝６５：３５の混合溶媒に溶解させた液に浸漬塗布することにより、乾燥後の膜厚２０μｍの電荷輸送層を設けた。このようにして得られた感光体ドラムをＡ１とする。
【００６８】
【化２】

【００６９】
実施例２
電荷輸送層用バインダー樹脂として製造例２で作製したポリカーボネート樹脂を用いたこと以外は実施例１と同様にして感光体Ａ２を得た。このポリカーボネート樹脂は、Ｍｖ＝４２，２００、Ｍｗ／Ｍｎ＝１．３２、Ｍｖ／Ｍｎ′＝１．１０である。
比較例１
電荷輸送層用バインダー樹脂として製造例６で作製したポリカーボネート樹脂を用いたこと以外は実施例１と同様にして感光体Ｂ１を得た。このポリカーボネート樹脂は、Ｍｖ＝３０，２００、Ｍｗ／Ｍｎ＝３．０２、Ｍｖ／Ｍｎ′＝１．４５である。
比較例２
電荷輸送層用バインダー樹脂として製造例７で作製したポリカーボネート樹脂を用いたこと以外は実施例１と同様にして感光体Ｂ２を得た。このポリカーボネート樹脂は、Ｍｖ＝４５，９００、Ｍｗ／Ｍｎ＝３．５５、Ｍｖ／Ｍｎ′＝１．５１である。
【００７０】
実施例３
表面が鏡面仕上げされた外径３０ｍｍ、長さ２５４ｍｍ、肉厚０．７５ｍｍのアルミニウム合金よりなるシリンダーを、先に調製した下引き層用分散液に浸漬塗布し、膜厚約１．３μｍの下引き層を形成した。このシリンダーを先に作製した電荷発生層用分散液βに浸漬し、その乾燥後の重量が０．３ｇ／ｍ²（膜厚約０．３μｍ）となるように電荷発生層を形成した。
次に、この電荷発生層を形成したシリンダーを、前記構造式（２）に示す電荷輸送性化合物５０部と、電荷輸送層用バインダー樹脂として製造例１で作製したポリカーボネート樹脂（粘度平均分子量約３０，９００、Ｍｗ／Ｍｎ＝１．３４、Ｍｖ／Ｍｎ′＝１．１５）１００部、シリコーンオイル（信越化学社製、商品名ＫＦ９６）０．０５部をテトラヒドロフラン：１，４−ジオキサン＝６５：３５の混合溶媒に溶解させた液に浸漬塗布することにより、乾燥後の膜厚２５μｍの電荷輸送層を設けた。このようにして得られた感光体ドラムをＡ３とする。
【００７１】
実施例４
電荷輸送層用バインダー樹脂として製造例２で作製したポリカーボネート樹脂を用いたこと以外は実施例３と同様にして感光体Ａ３を得た。このポリカーボネート樹脂は、Ｍｖ＝４２，２００、Ｍｗ／Ｍｎ＝１．３２、Ｍｖ／Ｍｎ′＝１．１０である。
比較例３
電荷輸送層用バインダー樹脂として製造例６で作製したポリカーボネート樹脂を用いたこと以外は実施例３と同様にして感光体Ｂ３を得た。このポリカーボネート樹脂は、Ｍｖ＝３０，２００、Ｍｗ／Ｍｎ＝３．２０、Ｍｖ／Ｍｎ′＝１．４５である。
比較例４
電荷輸送層用バインダー樹脂として製造例７で作製したポリカーボネート樹脂を用いたこと以外は実施例３と同様にして感光体Ｂ４を得た。このポリカーボネート樹脂は、Ｍｖ＝４５，９００、Ｍｗ／Ｍｎ＝３．５５、Ｍｖ／Ｍｎ′＝１．５１である。
【００７２】
実施例５
表面が鏡面仕上げされた外径３０ｍｍ、長さ２８５ｍｍ、肉厚１．０ｍｍのアルミニウム合金よりなるシリンダーの表面に、陽極酸化処理を行い、その後酢酸ニッケルを主成分とする封孔剤によって封孔処理を行うことにより、約６μｍの陽極酸化被膜（アルマイト被膜）を形成した。このシリンダーを先に作製した電荷発生層用分散液αに浸漬塗布し、その乾燥後の重量が０．３ｇ／ｍ²（膜厚約０．３μｍ）となるように電荷発生層を形成した。
次に、この電荷発生層を形成したシリンダーを、前記構造式（２）に示す電荷輸送性化合物５０部と、電荷輸送層用バインダー樹脂として製造例３で作製したポリカーボネート樹脂（粘度平均分子量約４１，９００、Ｍｗ／Ｍｎ＝１．３９、Ｍｖ／Ｍｎ′＝１．０４）１００部、シリコーンオイル（信越化学社製、商品名ＫＦ９６）０．０５部をテトラヒドロフラン：トルエン＝８０：２０の混合溶媒に溶解させた液に浸漬塗布することにより、乾燥後の膜厚２０μｍの電荷輸送層を設けた。このようにして得られた感光体ドラムをＡ５とする。
【００７３】
実施例６
電荷輸送層用バインダー樹脂として製造例４で作製したポリカーボネート樹脂を用いたこと以外は実施例５と同様にして感光体Ａ６を得た。このポリカーボネート樹脂は、Ｍｖ＝５２，９００、Ｍｗ／Ｍｎ＝１．３８、Ｍｖ／Ｍｎ′＝１．０４である。
比較例５
電荷輸送層用バインダー樹脂として製造例８で作製したポリカーボネート樹脂を用いたこと以外は実施例５と同様にして感光体Ｂ５を得た。このポリカーボネート樹脂は、Ｍｖ＝４６，８００、Ｍｗ／Ｍｎ＝３．６２、Ｍｖ／Ｍｎ′＝１．５２である。
比較例６
電荷輸送層用バインダー樹脂として製造例９で作製したポリカーボネート樹脂を用いたこと以外は実施例５と同様にして感光体Ｂ６を得た。このポリカーボネート樹脂は、Ｍｖ＝５６，９００、Ｍｗ／Ｍｎ＝３．８９、Ｍｖ／Ｍｎ′＝１．５４である。
【００７４】
実施例７
表面が鏡面仕上げされた外径３０ｍｍ、長さ２５４ｍｍ、肉厚０．７５ｍｍのアルミニウム合金よりなるシリンダーを、先に調製した下引き層用分散液に浸漬塗布し、膜厚約１．３μｍの下引き層を形成した。このシリンダーを先に作製した電荷発生層用分散液に浸漬し、その乾燥後の重量が０．３ｇ／ｍ²（膜厚約０．３μｍ）となるように電荷発生層を形成した。
次に、この電荷発生層を形成したシリンダーを、前記構造式（２）に示す電荷輸送性化合物５０部と、電荷輸送層用バインダー樹脂として製造例３で作製したポリカーボネート樹脂（粘度平均分子量約４１，９００、Ｍｗ／Ｍｎ＝１．３９、Ｍｖ／Ｍｎ′＝１．０４）１００部、シリコーンオイル（信越化学社製、商品名ＫＦ９６）０．０５部をテトラヒドロフラン：トルエン＝８０：２０の混合溶媒に溶解させた液に浸漬塗布することにより、乾燥後の膜厚２５μｍの電荷輸送層を設けた。このようにして得られた感光体ドラムをＡ７とする。
【００７５】
実施例８
電荷輸送層用バインダー樹脂として製造例４で作製したポリカーボネート樹脂を用いたこと以外は実施例７と同様にして感光体Ａ８を得た。このポリカーボネート樹脂は、Ｍｖ＝５２，９００、Ｍｗ／Ｍｎ＝１．３８、Ｍｖ／Ｍｎ′＝１．０４である。
比較例７
電荷輸送層用バインダー樹脂として製造例８で作製したポリカーボネート樹脂を用いたこと以外は実施例７と同様にして感光体Ｂ７を得た。このポリカーボネート樹脂は、Ｍｖ＝４６，８００、Ｍｗ／Ｍｎ＝３．６２、Ｍｖ／Ｍｎ′＝１．５２である。
比較例８
電荷輸送層用バインダー樹脂として製造例９で作製したポリカーボネート樹脂を用いたこと以外は実施例７と同様にして感光体Ｂ８を得た。このポリカーボネート樹脂は、Ｍｖ＝５６，９００、Ｍｗ／Ｍｎ＝３．８９、Ｍｖ／Ｍｎ′＝１．５４である。
【００７６】
＜感光体の評価＞
［電気特性評価］
次にこれらＡ１からＡ８、Ｂ１からＢ８の感光体を、感光体特性試験機（三菱化学（株）製）に装着し、帯電、露光、電位測定、除電のサイクルによる電気特性評価試験を行った。初期表面電位は−７００Ｖとし、露光はハロゲンランプの光を干渉フィルターで７８０ｎｍの単色光としたものを用いて、表面電位が−７００Ｖから−３５０Ｖに半減するのに要した露光量（半減露光量、Ｅ１／２）、４．７μＪ／ｃｍ²（電荷発生層用分散液αを用いて作製した感光体の場合、露光から電位測定までの時間は約３９０ｍｓ）または１．２μＪ／ｃｍ²（電荷発生層用分散液βを用いて作製した感光体の場合、露光から電位測定までの時間は約１００ｍｓ）照射した時点の表面電位（ＶＬ）を測定した。また、除電光には６６０ｎｍのＬＥＤ光を用いて、除電光照射後の残留電位（Ｖｒ）を測定した。測定は温度２５℃、湿度５０％ＲＨの環境下で行った。結果を表３に示す。
【００７７】
【表３】

【００７８】
表３で示される通り、実施例の感光体Ａ１ないしＡ８は、比較例の感光体Ｂ１ないしＢ８と比べて同等若しくは良好な電機特性を有している。
［耐刷試験による膜減り測定］
次に感光体Ａ１、Ａ２、Ｂ１、Ｂ２、Ａ５、Ａ６、Ｂ５、Ｂ６を市販のカラーレーザープリンター（エプソン社製 ＬＰ３０００Ｃ）に装着して常温常湿環境下においてモノクロ（黒）モードで２４０００枚のプリントを行った。
この際、プリントする前の感光層の膜厚、２４０００枚プリント後の膜厚を測定し、プリント１０，０００枚あたりの膜減り量を計算した。結果を表４に示す。
また、用いたバインダー樹脂のＭｖを横軸に１０，０００あたりの膜減り量を縦軸にとってプロットしたものを図１、図２に示す。
また、感光体Ａ３、Ａ４、Ｂ３、Ｂ４、Ａ７、Ａ８、Ｂ７、Ｂ８を市販のモノクロレーザープリンター（レックスマーク社製、Ｏｐｔｒａ Ｓ２４５０、Ａ４縦送りで２４枚／分、ＤＣ印加のローラー帯電、ローラー転写）に装着して常温常湿下において３０，０００枚のプリントを行った。プリント前後の膜厚の差から１０，０００枚あたりの膜減り量を計算した。結果を表５に示す。
また、用いたバインダー樹脂のＭｖを横軸に１０，０００あたりの膜減り量を縦軸にとってプロットしたものを図３、図４に示す。
【００７９】
【表４】

【００８０】
【表５】

【００８１】
【発明の効果】
本発明のポリカーボネートは従来使用されているポリカーボネートに比べ耐摩耗性に優れている為、耐熱性や高い表面硬度が要求される用途に適している。また、電子写真感光体において、本発明のポリカーボネートを用いることにより、優れた電気特性を示し、感光体表面の耐摩耗性を著しく向上させることができる。
【図面の簡単な説明】
【図１】粘度平均分子量と膜減り
【図２】粘度平均分子量と膜減り
【図３】粘度平均分子量と膜減り
【図４】粘度平均分子量と膜減り[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to electrophotographic photosensitive.To the bodyIn particular, narrow molecular weight distributionIRecarbonate treeFatThe present invention relates to an electrophotographic photoreceptor formed using a binder resin for a photosensitive layer.
[0002]
[Prior art]
In recent years, electrophotographic technology has been widely used and applied not only in the field of copying machines but also in the field of various printers because of its immediacy and high-quality images. Photoconductors, the core of electrophotographic technology, have been used as conventional photoconductive materials for inorganic photoconductors such as selenium, arsenic-selenium alloys, cadmium sulfide, and zinc oxide. A photoreceptor using an organic photoconductive material having advantages such as easy and easy manufacture is mainly used. However, organic photoreceptors have a shorter life than inorganic photoreceptors such as amorphous silicon, and further improvements are required.
[0003]
Since the electrophotographic photosensitive member is repeatedly used in an electrophotographic process, that is, a cycle of charging, exposure, development, transfer, cleaning, static elimination, and the like, it is deteriorated by various stresses during that time. Such deterioration includes, for example, strongly oxidative ozone and NOx generated from a corona charger normally used as a charger, which chemically damages the photosensitive layer, or a carrier (current) generated by image exposure is exposed to light. There are chemical and electrical degradations due to flowing in the layer, static elimination light, and decomposition of the photosensitive layer composition by external light. Further, there is mechanical deterioration such as abrasion of the surface of the photosensitive layer due to rubbing of a cleaning blade, a magnetic brush or the like, contact with a developer, paper, and the like, and film peeling. In particular, such damage on the surface of the photosensitive layer is likely to appear on the copy image, and directly impairs the image quality, which is a major factor that limits the life of the photoreceptor. In addition, if the photosensitive layer is highly worn, the film thickness becomes thin immediately and sufficient charging cannot be obtained, resulting in a short life. That is, in order to develop a long-life photoconductor, it is essential to increase the mechanical strength as well as the electrical and chemical durability.
[0004]
As a photoreceptor using an organic photoconductive material, a so-called dispersion type photoreceptor in which a photoconductive fine powder is dispersed in a binder resin, and a laminate type photoreceptor in which a charge generation layer and a charge transport layer are laminated are known. ing. In addition, in the laminated type photoreceptor, there are a forward laminated type photoreceptor in which the charge generation layer and the charge transport layer are laminated in this order on the conductive substrate, and a reverse laminated type photoreceptor in which the charge transport layer and the charge generation layer are laminated in this order. Are known. Multilayered photoreceptors can be obtained by combining highly efficient charge generating substances and charge transporting substances to obtain highly sensitive photoreceptors, a wide range of material selection, and highly safe photoreceptors. Has been developed and put into practical use as the mainstream of photoconductors because of its high productivity and relatively advantageous cost.
In general, in the case of a sequentially laminated type photoreceptor, it is the charge transport layer that is the outermost layer that is subjected to an electrical, chemical or mechanical load. The charge transport layer is usually composed of a binder resin and a charge transport material, and it is the binder resin that substantially determines the strength, but it does not have sufficient mechanical strength, and has a higher durability. The body is desired.
The binder resin for forming the charge transport layer of the photoreceptor includes vinyl polymers such as polymethyl methacrylate, polystyrene, and polyvinyl chloride, and copolymers thereof, polycarbonate, polyester, polysulfone, phenoxy, epoxy, silicone resin, etc. Thermoplastic resins and various thermosetting resins have been used. Among them, polycarbonate resins have relatively excellent performance, and various polycarbonate resins have been developed and put into practical use. (See Patent Documents 1 to 4).
However, conventional organophotoreceptors using polycarbonates have insufficient mechanical strength, so they have disadvantages such as large wear and scratches, so that they have practically limited printing performance. The current situation remains.
[0005]
[Patent Document 1]
JP 50-98332 A
[Patent Document 2]
JP 59-71057 A
[Patent Document 3]
JP 59-184251
[Patent Document 4]
JP-A-5-21478
[0006]
[Problems to be solved by the invention]
  The object of the present invention is to provide an electrophotographic photosensitive material that has excellent mechanical properties such as printing durability, abrasion resistance, and slipping property in repeated use, and also has excellent electrical characteristics.BodyIt is to provide.
[0007]
[Means for Solving the Problems]
  Therefore, as a result of intensive studies on the improvement of the abrasion resistance of the surface of the electrophotographic photosensitive member, the present inventors have significantly improved the surface strength and durability by using a specific polycarbonate resin as a binder resin for the photosensitive layer. The inventors have found that an electrophotographic photoreceptor excellent in the above can be obtained, and have reached the present invention.
  That is, the gist of the present invention is as follows.
  An electrophotographic photosensitive member having at least a photosensitive layer on a conductive support.The binder resin of the photosensitive layer isBy reacting a carbonate-forming compound with a dihydroxy compound to form an oligomer and polymerizing the oligomer in the presence of a catalyst.manufacturedPolycarbonate resinBecauseThe catalyst used is a salt of a compound having a basicity of 7 or less as the pKa value of the hydrochloride, and is a polycarbonate resin. The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography in the polycarbonate resin The number average molecular weight calculated from the viscosity average molecular weight (Mv) calculated by the following formula (I) and the number of molecular ends, and the ratio (Mw / Mn) of the number average molecular weight (Mn) to 2.4 or less Polycarbonate resin whose ratio (Mv / Mn ′) to (Mn ′) is 1.4 or lessIsElectrophotographic photosensitivebody,
InExist.
[0008]
[Expression 2]
ηsp / C = [η] × (1 + 0.28ηsp) Formula (I)
[Η] = 1.23 × 10^-Four× Mv^0.83
(In the formula (I), ηsp is the specific viscosity of a polycarbonate resin methylene chloride solution measured at 20 ° C., and C is the concentration of the methylene chloride solution. As the methylene chloride solution, the concentration of the polycarbonate resin is 0.6 g / dl)
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail. The polycarbonate resin in the present invention is produced by reacting a carbonate-forming compound and a dihydroxy compound. Typically, an aromatic compound (aromatic dihydroxy compound) having two phenolic hydroxyl groups represented by bisphenol A is reacted with phosgene to form an oligomer, and this oligomer is used in the absence of an end-capping agent. And polymerized in the presence of a catalyst such as pyridine hydrochloride or quinoline hydrochloride.
Here, the carbonate-forming compound is a compound capable of forming a carbonate bond [—O—CO—O—] in the polycarbonate main chain by a polymer forming reaction such as a condensation reaction or an exchange reaction. Specifically, phosgene And carbonic acid diester. Examples of the carbonic acid diester include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and ditolyl carbonate.
[0010]
Examples of the dihydroxy compound include an aliphatic dihydroxy compound and an aromatic dihydroxy compound. Examples of the aromatic dihydroxy compound include an aromatic compound having two phenolic hydroxyl groups.
Specific examples of preferred dihydroxy compounds used in the present invention include bisphenol A, hydroquinone, resorcin, dihydroxydiphenol, bis (hydroxyphenyl) alkane, bis (hydroxyphenyl) cycloalkane, bis (hydroxyphenyl) sulfide, Bis (hydroxyphenyl) ether, bis (hydroxyphenyl) ketone, bis (hydroxyphenyl) sulfone, bis (hydroxyphenyl) sulfoxide, bis (hydroxyphenyl) dialkylbenzene, and derivatives thereof having an alkyl or halogen substituent in the nucleus Is mentioned. Among these, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 1,1-bis (4- Hydroxyphenyl) cyclohexane and 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane.
[0011]
A small amount of a branching agent having 3 or more functional groups can be used in combination with the dihydroxy compound. Such branching agents are known, for example 2,4-bis (4'-hydroxyphenyl-isopropyl) phenol, 2,6-bis (2'-hydroxy-5'-methylbenzyl) -4-methylphenol, 2- (4-hydroxyphenyl) -2- (2,4-dihydroxyphenyl) propane, 1,4-bis (4,4′-dihydroxytriphenylmethyl) benzene, 2,4-dihydroxybenzoic acid, trimesic acid, Cyanuric chloride, bis (4'-hydroxyphenyl) -2-oxo-2,3-dihydroxyindole, 3,3-bis (4-hydroxy-3-methylphenyl) -2-oxo-2,3-dihydroindole, etc. Is mentioned. Of these, those having three or more phenolic hydroxyl groups are preferred. The amount of branching agent used varies depending on the target degree of branching, but is usually used in an amount of 0.05 to 2 mol% with respect to the aromatic compound having two phenolic hydroxyl groups. Note that when a branching agent is used in combination, the viscosity average molecular weight (Mv) tends to increase.
[0012]
  Next, a polycarbonate having a narrow molecular weight distribution used in the present invention is disclosed in, for example, JP-A-200200.2As described in JP-A-69168, the catalyst can be produced by using a hydrochloride having a pKa value of 7 or less, preferably 6 or less, more preferably 5.5 or less. That is, by using a catalyst having a weak basicity, the nucleophilic substitution reaction can be preferentially caused only from the other ionized terminal (phenylene-ONa terminal) without ionizing the terminal of the chloroformate molecule. Since the reaction mechanism is different from the conventional condensation polymerization at the time of producing a polycarbonate resin that proceeds only by a single reaction, a polycarbonate having a molecular weight distribution according to the Poisson distribution is obtained as a result.
[0013]
Furthermore, the production of the polycarbonate resin according to the present invention is preferably an interfacial polymerization reaction in which an aqueous phase and an organic phase are present as described later. In this interfacial polymerization reaction, the reaction proceeds by a nucleophilic substitution reaction from only the ionized end, and therefore, it is necessarily a sequential reaction that can only produce growth corresponding to the interfacial area per volume. When the molecular weight is large and the condensed species disappears, the chloroformate molecule terminal is hydrolyzed by NaOH in the aqueous phase, and the molecular weight elongation stops as the OH terminal. When the interfacial area per volume is small, as a side reaction, the chloroformate end, which is the molecular end of the growth reaction, undergoes a hydrolysis reaction with NaOH in the aqueous phase, resulting in growth to a molecular weight higher than that. The molecular weight is not obtained, that is, the molecular weight is controlled by the interfacial area. The background to the establishment of such a reaction is that the growth reaction proceeds at a much faster rate than the hydrolysis reaction.
[0014]
In the conventional condensation polymerization that occurs during the production of a general polycarbonate resin, there is no such imbalance in the reaction. In the conventional condensation polymerization, a catalyst having a high pKa value is used, and the chloroformate terminal is also activated in an ion-like manner by the catalyst having a high pKa value, and the reaction activity is almost the same as that of the ionized phenylene-ONa terminal. Is obtained at both molecular ends, and a condensate having a general molecular weight distribution according to Flory's most probable distribution can be obtained. .
[0015]
As a catalyst satisfying the above conditions, a salt of a nitrogen-containing heterocyclic compound is used. For example, a ring carbon atom such as pyridine, quinoline, isoquinoline, picoline, acridine, pyrazine, pyridazine, pyrimidine, 2,4,6-trimethyltriazine may be substituted with an alkyl group, an alkoxy group, a halogen atom, or the like. A salt of a compound having a saturated nitrogen-containing 6-membered ring is used. Further, salts of compounds having an unsaturated nitrogen-containing five-membered ring such as phenothiazine, 2-methylimidazole, benzimidazole, benzotriazole, benzothiazole and the like are also used. Of these nitrogen-containing heterocyclic compounds, pyridine, quinoline, picoline, imidazoles, pyrazoles, triazoles, and the like are preferably used. These catalysts are used so that it may become 0.01-1 mol% normally with respect to the aromatic compound which has two phenolic hydroxyl groups of a raw material. Preferably it is used so that it may become 0.05-0.5 mol%, especially 0.05-0.15 mol%. These nitrogen-containing heterocyclic compounds are used in the salt form such as hydrochloride, sulfate, nitrate, hydrobromide, etc., but in the reaction system, they are in a dissociation equilibrium state between the free base form and the salt form. It is thought that there is.
[0016]
These catalysts may be present in the reaction system from the beginning of the reaction between the aromatic compound having two phenolic hydroxyl groups and phosgene, or may be added to the reaction system after this reaction. However, if the addition of the catalyst is delayed, it becomes difficult to control the molecular weight of the polycarbonate resin to be produced. Accordingly, the catalyst is preferably added to the reaction system from the beginning of the reaction with phosgene until the molecular weight starts to increase, and in terms of viscosity average molecular weight (Mv), Mv reaches 2000 to 3000.
[0017]
On the other hand, as a condensation catalyst, you may use together the well-known thing used for the two-phase interfacial polymerization method. Usually, trialkylamine, N-ethylpyrrolidone, N-ethylpiperidine, N-ethylmorpholine, N-isopropylpiperidine, or N-isopropylmorpholine is used. Of these, triethylamine or N-ethylpiperidine is preferably used. The condensation catalyst is preferably supplied to the reaction system after phosgene is supplied. In the reaction, an aqueous solution prepared by dissolving an aromatic compound having two phenolic hydroxyl groups and caustic soda in water and an inert organic solvent are mixed to prepare an emulsion, and phosgene is supplied thereto. React to produce oligomers. The molar ratio of the aromatic compound having two phenolic hydroxyl groups and caustic soda in the aqueous solution is usually 1: 1.8 to 3.5, preferably 1: 2.0 to 3.2. A small amount of a reducing agent such as hydrosulfite is preferably added to the aqueous solution. The ratio of the organic phase to the aqueous phase is preferably 0.2 to 1.0 (volume ratio). As the inert organic solvent, a phosgene that is a raw material, an oligomer generated by the reaction, and a polycarbonate resin are dissolved under reaction conditions, but those that do not dissolve in water are used. The amount used may be an amount capable of dissolving the produced oligomer, but is usually used so that the concentration of the produced oligomer solution is 10 to 40% by weight.
[0018]
Typical inert organic solvents include aliphatic hydrocarbons such as hexane and n-heptane, methylene chloride, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, tetrachloroethane, dichloropropane and 1,2-dichloroethylene. Chlorinated aliphatic hydrocarbons, aromatic hydrocarbons such as benzene, toluene and xylene, chlorinated aromatic hydrocarbons such as chlorobenzene, o-dichlorobenzene and chlorotoluene, and other substituted aromatic carbons such as nitrobenzene and acetophenone Examples include hydrogen. Of these, chlorinated hydrocarbons such as methylene chloride or chlorobenzene are preferably used. These inert organic solvents can be used alone or as a mixture with other solvents. The oligomer formation reaction is performed at 80 ° C. or lower, preferably 70 ° C. or lower. If the reaction temperature is too high, side reactions will increase and the phosgene intensity will deteriorate. Conversely, a low reaction temperature is advantageous in terms of reaction control, but the reaction is a large exothermic reaction. Therefore, the lower the temperature of the reaction system, the higher the cost for maintaining this temperature. Therefore, considering these points, the reaction is usually carried out at 10 to 65 ° C.
[0019]
The oligomer produced as described above is then polymerized to give a polycarbonate resin. Usually, the reaction mixture obtained in the above oligomer production step is separated into an aqueous phase and an organic phase in which the oligomer is dissolved, and is necessary so that the oligomer concentration in this organic phase is 5 to 30% by weight. Depending on the addition of inert organic solvent. Next, an aqueous solution of caustic soda is newly added to the oligomer solution, and the aforementioned catalyst is further added to cause interfacial polymerization. In this case, the ratio of the aqueous phase to the organic phase is preferably 0.2 to 2.0 (volume ratio). The temperature of the interfacial polymerization reaction varies depending on the organic solvent used, but in the case of methylene chloride, it is usually carried out at 10 to 35 ° C.
[0020]
After completion of the polymerization, the organic phase is washed with an aqueous caustic soda solution until the content of the chloroformate group of the polycarbonate resin is 0.1 μeq / g or less, then washed with an aqueous acid solution to neutralize the alkali and remove the catalyst. Further, the electrolyte is completely removed by washing with water. Finally, the organic solvent is removed from the organic phase by evaporation to obtain a polycarbonate resin. This polycarbonate resin has a very narrow molecular weight distribution in the state as produced by the interfacial polycondensation reaction, that is, without performing a treatment for adjusting the molecular weight distribution such as fractional precipitation or extraction and removal of low molecular weight components.
[0021]
The polycarbonate resin obtained by the above method allows the reaction to occur without using a terminal blocking agent at any stage of the oligomer formation reaction and the polymerization reaction from the oligomer to the polycarbonate resin. is there. If a polycarbonate resin whose molecular terminal is sealed with a long-chain alkyl group is desired, the polycarbonate resin obtained above is reacted with a long-chain alcohol, a long-chain carboxylic acid or a reactive derivative thereof. A polycarbonate resin whose ends are sealed to a desired degree can be obtained.
[0022]
The polycarbonate resin in the present invention can be produced by the above method, and the ratio (Mw / Mn) of polystyrene-equivalent weight average molecular weight (Mw) to number average molecular weight (Mn) measured by gel permeation chromatography is 2. The ratio (Mv / Mn ′) of the viscosity average molecular weight (Mv) calculated by the following formula (I) and the number average molecular weight (Mn ′) calculated from the number of molecular ends is 1.4 or less. It is as follows.
[0023]
[Equation 3]
ηsp / C = [η] × (1 + 0.28ηsp) Formula (I)
[Η] = 1.23 × 10^-Four× Mv^0.83
(In the formula, ηsp is the specific viscosity measured at 20 ° C. for a methylene chloride solution of polycarbonate resin, and C is the concentration of this methylene chloride solution. The methylene chloride solution has a polycarbonate resin concentration of 0.6 g / dl. Is used)
[0024]
A preferable polycarbonate resin in the present invention has Mw / Mn of 2.4 or less, particularly 2.0 or less. Mv / Mn ′ is preferably 1.3 or less, particularly preferably 1.2 or less. Mw / Mn and Mv / Mn ′ are both indices indicating the width of the molecular weight distribution, and a small value means that the molecular weight distribution is narrow. There have been proposals for the production of polycarbonate resins having a narrow molecular weight distribution, but the products obtained by these conventional production methods have a value far exceeding 2 from Mw / Mn calculated from the glass transition point. Since the value is close to 3, the polycarbonate resin used in the present invention is different from this and has a remarkably narrow molecular weight distribution.
[0025]
Mv is preferably 5,000 to 200,000, more preferably 10,000 to 150,000, and most preferably 20,000 to 100,000. If Mv is less than 5,000, the strength is insufficient and impractical, and if it exceeds 200,000, it is difficult to apply an appropriate film thickness.
[0026]
<Conductive support>
The electrophotographic photoreceptor of the present invention is constituted by forming a photosensitive layer on a conductive support. As the conductive support on which the photosensitive layer is formed, any of those used in known electrophotographic photoreceptors can be used. Specifically, for example, drums, sheets made of metal materials such as aluminum, stainless steel, copper, nickel, zinc, indium, gold, and silver, laminates of these metal foils, deposits, or aluminum, copper, palladium on the surface Insulating supports such as polyester film provided with a conductive layer such as tin oxide, indium oxide, and conductive polymer, paper, and glass. Furthermore, a plastic film, a plastic drum, paper, a paper tube, and the like obtained by applying a conductive material such as metal powder, carbon black, copper iodide, and a polymer electrolyte together with an appropriate binder to conduct a conductive treatment may be used. Further, a plastic sheet or drum containing a conductive material such as metal powder, carbon black, or carbon fiber and becoming conductive can be used. Moreover, the plastic film and belt which carried out the electroconductive process with electroconductive metal oxides, such as a tin oxide and an indium oxide, are mentioned. Thus, the surface of the conductive support can be subjected to various treatments, for example, surface oxidation treatment or chemical treatment within a range that does not affect the image quality. The shape can be any shape such as a drum, a sheet, a belt, a seamless belt, and the like.
[0027]
<Blocking layer>
A known blocking layer that is usually used may be provided between the conductive support and the photosensitive layer. Examples of the blocking layer include an anodized aluminum film, an inorganic layer such as aluminum oxide and aluminum hydroxide, an organic layer such as polyvinyl alcohol, casein, polyvinyl pyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide and polyamide. Layers are used. When the organic layer is used as a blocking layer, a metal oxide such as titania, alumina, silica, and zirconium oxide or a metal fine powder such as copper, silver, and aluminum may be dispersed.
[0028]
Although the film thickness of these blocking layers can be set suitably, it is 0.05-20 micrometers normally, Preferably it is the range of 0.1-10 micrometers.
<Configuration of photosensitive layer>
As the photosensitive layer, any of a so-called laminated type photosensitive layer and a dispersion type photosensitive layer can be used. However, in order to comprehensively consider the mechanical properties, electrical characteristics, manufacturing stability, etc. A laminate type photoreceptor is preferred.
[0029]
<Charge generating material>
Examples of the charge generation material contained in the photosensitive layer include oxide semiconductors such as titanium oxide, silicon materials such as amorphous silicon, other inorganic photoconductive substances, phthalocyanines, azo dyes, quinacridones, polycyclic quinones, pyrylium salts, Various organic pigments and dyes such as perylene, indigo, thioindigo, anthanthrone, pyrantrone, and cyanine can be used. Among them, perylene, metal-free phthalocyanine, copper, indium chloride, gallium, silicon, tin, titanium, zinc, vanadium and other metals, or oxides, chlorides, hydroxide coordinated phthalocyanines, or monoazo, Azo pigments such as bisazo, trisazo and polyazos are desirable.
Further, two or more kinds of charge generating materials may be mixed and used for the purpose of improving the chargeability at the first rotation, reducing light fatigue, and adjusting sensitivity.
[0030]
<Charge transport material>
In the present invention, charge transport materials used in the photosensitive layer include diphenoquinone derivatives, aromatic nitro compounds such as 2,4,7-trinitrofluorenone, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, oxalates. Heterocyclic compounds such as diazole derivatives, pyrazoline derivatives, thiadiazole derivatives, aniline derivatives, hydrazone compounds, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine compounds, a combination of these compounds, or from these compounds And a polymer having such a group in the main chain or side chain. In addition, you may use the said charge transport material in mixture of 2 or more types.
[0031]
<Dispersion type photosensitive layer>
When the electrophotographic photosensitive member of the present invention has a dispersion type photosensitive layer, the charge generating material is dispersed or dissolved in the layer containing the polycarbonate resin of the present invention together with the charge transporting material.
At this time, the particle size of the charge generating material needs to be sufficiently small, and is preferably 1 μm or less, more preferably 0.5 μm or less.
The amount of the charge generating material dispersed or dissolved in the photosensitive layer is, for example, in the range of 0.5 to 50% by weight. However, if the amount is too small, sufficient sensitivity cannot be obtained. And is preferably used in the range of 1 to 20% by weight.
Furthermore, the photosensitive layer may contain various additives such as an antioxidant, an electron-withdrawing compound, a leveling agent, a lubricant, an ultraviolet absorber, and a sensitizer as necessary.
In addition, various additives for improving the mechanical strength and durability of the coating film can also be used. Examples of such additives include known plasticizers, various stabilizers, fluidity imparting agents, and crosslinking agents.
The resulting coating solution is coated on a conductive support and dried to form a photosensitive layer. Usually, the coating solution is used in a thickness of several μm to several tens of μm, preferably 10 to 45 μm, more preferably 20 to 35 μm.
[0032]
<Laminated photosensitive layer>
i) Charge generation layer
When the electrophotographic photoreceptor of the present invention has a laminated photosensitive layer, the charge generating material is used alone or in combination with a binder resin to form the charge generating layer.
Disperse and dissolve the charge generating material in an appropriate dispersion medium using a ball mill, ultrasonic disperser, paint shaker, attritor, sand grinder, etc., and add a binder resin as necessary to adjust the coating solution. The coating solution is dried by a coating method such as dipping method, spray method, bar coater method, blade method, roll coater method, wire bar coating method, knife coater coating method.
[0033]
Examples of the binder resin include polyester resin, polyvinyl acetate, polyester, polycarbonate, polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, phenoxy resin, epoxy resin, urethane resin, cellulose ester, cellulose ether, styrene, vinyl acetate, vinyl chloride, Examples thereof include polymers and copolymers of vinyl compounds such as acrylic acid esters, methacrylic acid esters, vinyl alcohol, and ethyl vinyl ether, polyamides, and silicon resins. In this case, the charge generation material is usually 5 to 500 parts by weight, preferably 20 to 300 parts by weight, based on 100 parts by weight of the binder resin. The film thickness of the charge generation layer is usually 0.01-5 μm, preferably 0.05-2 μm, more preferably 0.15-0.8 μm. In addition, the charge generation layer may contain various additives such as a leveling agent, an antioxidant, and a sensitizer for improving the coating property as necessary.
When the charge generating material is used alone, the coating solution may be prepared and applied without adding a binder to the dispersion, or may be formed by a method such as vapor deposition or sputtering.
[0034]
ii) Charge transport layer
When the electrophotographic photoreceptor of the present invention has a function-separated type photosensitive layer, the charge transport material is mixed with a binder resin containing the polycarbonate resin of the present invention to form a charge transport layer.
The ratio of the charge transport material and the binder resin is usually 10 to 200 parts by weight, preferably 30 to 150 parts by weight, based on 100 parts by weight of the binder resin.
The thickness of the charge transport layer is usually 10 to 50 μm, preferably 13 to 35 μm.
Furthermore, the charge transport layer may contain various additives such as an antioxidant, an electron-withdrawing compound, a leveling agent, a lubricant, an ultraviolet absorber, a sensitizer, and other charge transport materials as necessary. .
In addition, various additives for improving the mechanical strength and durability of the coating film can be used. Examples of such additives include known plasticizers, various stabilizers, fluidity imparting agents, and crosslinking agents.
[0035]
<Coating solution for forming photosensitive layer>
Solvents and dispersion media used when applying the above layers include butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, Xylene, chloroform, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, dichloromethane, tetrahydrofuran, dioxane, methyl Examples include alcohol, ethyl alcohol, isopropyl alcohol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and methyl cellosolve.
These solvents may be used alone or in combination of two or more.
[0036]
<Photosensitive layer forming method>
Examples of the photosensitive layer coating method include a spray coating method, a spiral coating method, a ring coating method, and a dip coating method.
Spray coating methods include air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, and hot airless spray. Considering the degree of conversion, adhesion efficiency, etc., in the rotary atomizing electrostatic spray, the conveying method disclosed in the republished Japanese Patent Publication No. 1-805198, that is, the cylindrical workpiece is rotated while the axial direction is spaced. By continuously transporting the electrophotographic photosensitive member, an electrophotographic photosensitive member excellent in film thickness uniformity can be obtained with a comprehensively high adhesion efficiency.
[0037]
Examples of the spiral coating method include a method using a liquid injection coating machine or a curtain coating machine disclosed in Japanese Patent Laid-Open No. 52-119651, and paint from a minute opening disclosed in Japanese Patent Laid-Open No. 1-2231966. There are a method of continuously flying in a streak shape, a method using a multi-nozzle body disclosed in JP-A-3-193161, and the like.
As an example of the dip coating method, the following coating formation procedure of the charge transport layer may be mentioned.
Using a charge transport material, binder resin, solvent, etc., the total solid concentration is 15% or more, more preferably 40% or less, and the viscosity is usually 50 centipoise or more and 700 centipoise or less, preferably 100 centipoise or more and 500 centipoise. The following coating liquid for forming the charge transport layer is prepared.
After the coating film is formed, the coating film is dried, and the drying temperature and time are adjusted so that necessary and sufficient drying is performed. A drying temperature is 100-250 degreeC normally, Preferably it is 110-170 degreeC, More preferably, it is the range of 115-140 degreeC. As a drying method, a hot air dryer, a steam dryer, an infrared dryer, a far infrared dryer, or the like can be used.
The electrophotographic photoreceptor of the present invention thus obtained maintains excellent printing durability and slipperiness over a long period of time, and is suitable for electrophotographic fields such as copying machines, printers, fax machines, and plate-making machines.
[0038]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded. “Parts” used in Examples and Comparative Examples indicates “parts by weight” unless otherwise specified.
<Preparation of binder resin>
The evaluation method in the production example is as follows.
(1) Measurement of gel permeation chromatography
Equipment: Tosoh Corporation product, HLC-8020
Columns: Four columns (diameter: 7.8 mmφ, length: 300 mm) packed with TSK 5000HLX, 4000HLX, 3000HLX, and 2000HLX (all manufactured by Tosoh Corporation) were used as fillers.
Detector: Refractometer
Eluent: Tetrahydrofuran
Calibration curve: Standard polystyrene (molecular weight; 761 (Mw / Mn ≦ 1.14), 2000 (Mw / Mn ≦ 1.20), 4000 (Mw / Mn ≦ 1.06), 9000 (Mw) manufactured by Chemco Corporation /Mn≦1.04), 17500 (Mw / Mn ≦ 1.03), 50000 (Mw / Mn ≦ 1.03), 233000 (Mw / Mn ≦ 1.05), 600000 (Mw / Mn ≦ 1.05) ) And 900,000 (Mw / Mn ≦ 1.05).
Operation: Mw and Mn were determined in terms of polystyrene from the chart obtained by detecting the difference in refractive index, and Mw / Mn was calculated. The baseline at this time was calculated by connecting the point where the base before the rising of the high molecular weight was faithfully extended as it was and the point where it returned to the original baseline on the low molecular weight side while the device was completely stable. In addition, it was confirmed that the above-mentioned standard polystyrene was measured and all were within the standard.
[0039]
(2) Measurement of number average molecular weight (Mn ′)
The ends of the polycarbonate resin produced without using the end-capping agent and the remaining ends not terminated with the terminator are all OH groups. The terminal OH group was colored with titanium tetrachloride under the acidity of acetic acid, and the terminal group was quantified by measuring the absorbance at a wavelength of 480 nm. The number average molecular weight (Mn ′) was calculated by the following formula (II).
Mn ′ = 10⁶/ (Number of terminal groups (μeq / g) × 1/2) Formula (II)
[0040]
Further, when a terminal blocking agent is used in the polymerization, it is calculated from the number of terminal OH groups obtained by the above measurement and the amount of the sealing agent added, assuming that the terminal blocking agent is all bonded to the terminal. The total with the number of terminal groups on the end was taken as the number of terminal groups. In addition, the polycarbonate resin polymerized in the presence of the end-capping agent was subjected to alkali hydrolysis in a preliminary experiment, and the amount of the end-capping agent bonded was quantified, and all the used end-capping agents were bonded to the molecular ends. I have confirmed that.
[0041]
(3) Measurement of viscosity average molecular weight (Mv)
It calculated | required based on following formula (I).
[0042]
[Expression 4]
ηsp / C = [η] × (1 + 0.28ηsp) Formula (I)
[Η] = 1.23 × 10^-Four× Mv^0.83
In the formula, ηsp is the specific viscosity measured at 20 ° C. for a methylene chloride solution of polycarbonate resin, and C is the concentration of this methylene chloride solution. As the methylene chloride solution, a polycarbonate resin having a concentration of 0.6 g / dl was used.
[0043]
[Production Example 1]
An aqueous solution in which 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as “bisphenol A”) is dissolved at 35 ° C. and then cooled to 25 ° C. in a caustic soda aqueous solution in which hydrosulfite is dissolved; The cooled methylene chloride is continuously supplied to a stainless steel pipe having an inner diameter of 6 mm and mixed, and the mixed solution is supplied to a homomixer (product of Tokushu Kaika Co., Ltd., TK homomic line flow LF-500 type). And emulsified to prepare an emulsion. The supply amount to the pipe is 16.31 kg / Hr of bisphenol A, 5.93 kg / Hr of caustic soda, 101.1 kg / Hr of water, 0.018 kg / Hr of hydrosulfite, and 68.0 kg / Hr of methylene chloride. The produced emulsion was allowed to flow through a pipe reactor having an inner diameter of 6 mm into a PTFE (polytetrafluoroethylene) pipe reactor having an inner diameter of 6 mm and a length of 34 m. Liquefied phosgene, cooled to 0 ° C. at the same time, was supplied to the pipe reactor at 7.5 kg / Hr for reaction to produce oligomers. The flow rate of the pipe reactor is 1.7 m / sec. As phosgene, phosgene cooled to −5 ° C. was passed through SV = 3 into a cylindrical container having a diameter of 55 mm and a height of 500 mm filled with the following activated carbon (trade name: Taihei Chemical Co., Ltd., trade name: Yokokor S). The purified product was used.
[0044]
Various physical properties of activated carbon cocool S (product of Taihei Chemicals)
True density: 2.1 g / ml
Porosity: 40%
Specific surface area: 1200m²/ G
Pore volume: 0.86 ml / g
[0045]
In the pipe reactor, the temperature rose to 60 ° C, but was 35 ° C at the outlet due to external cooling. The reaction mixture was allowed to stand and separate into an aqueous phase and an oil phase. 30 kg was fractionated from the obtained oil phase, and charged into a reaction vessel with an internal volume of 200 liters with a Faudler blade.
Next, 16 kg of methylene chloride and 32 kg of water were added thereto, and after cooling to 3 ° C. with stirring in a nitrogen atmosphere, pyridine hydrochloride as a catalyst was added at a ratio of 0.02 mol% with respect to bisphenol A, and 25% 4.15 kg of an aqueous caustic soda solution was added and a polymerization reaction was carried out for 60 minutes with stirring at 400 rpm, thereby producing a polycarbonate resin. At this time, the internal temperature of the polymerization rose to 11 ° C.
[0046]
To this reaction mixture, 3.04 mol% of benzoyl chloride as an end terminator with respect to bisphenol A and caustic soda equivalent to the terminator were added and stirred for 60 minutes while maintaining the same temperature. To the reaction mixture, 35 kg of methylene chloride and 10 kg of water were added, stirred for 20 minutes at room temperature, and allowed to stand to separate the aqueous phase and the organic phase. To the organic phase, 28 kg of 0.1N hydrochloric acid was added and stirred for 15 minutes, and then allowed to stand to separate the aqueous phase and the organic phase. As a result of repeating the washing operation of adding 28 kg of pure water to this organic phase and stirring for 15 minutes and then allowing it to stand to separate into an aqueous phase and an oil phase, chlorine ions were no longer detected in the aqueous phase. The washing operation was stopped. From the organic phase, methylene chloride was removed by evaporation with a kneader, and the resulting powder was dried to obtain a polycarbonate resin. Table 1 shows polymerization conditions and physical properties of the obtained polycarbonate resin.
[0047]
[Production Example 2]
In Production Example 1, the stirring rotation speed during the polymerization reaction was changed to 420, and the amount of caustic soda added at the same time as the end terminator and the end terminator was changed to 2.45 mol% with respect to bisphenol A. In the same manner as in Example 1, polycarbonate resin was produced. Table 1 shows the physical properties of the obtained polycarbonate resin.
[0048]
[Production Example 3]
An aqueous solution in which 1,1-bis (4-hydroxyphenyl) cyclohexane (hereinafter referred to as “bisphenol Z”) is dissolved at 35 ° C. and then cooled to 25 ° C. in a caustic soda aqueous solution in which hydrosulfite is dissolved; The cooled methylene chloride is continuously supplied to a stainless steel pipe having an inner diameter of 6 mm and mixed, and the mixed solution is supplied to a homomixer (product of Tokushu Kaika Co., Ltd., TK homomic line flow LF-500 type). And emulsified to prepare an emulsion. The feed rates to the pipe are bisphenol Z 8.63 kg / Hr, caustic soda 3.86 kg / Hr, water 110.9 kg / Hr, hydrosulfite 0.018 kg / Hr, and methylene chloride 68.0 kg / Hr. The produced emulsion was passed through a pipe having an inner diameter of 6 mm and a PTFE pipe reactor having an inner diameter of 6 mm and a length of 34 m. Liquefied phosgene, cooled to 0 ° C. at the same time, was supplied to the pipe reactor at 3.4 kg / Hr for reaction to produce oligomers. The flow rate of the pipe reactor is 1.7 m / sec. The phosgene was purified by passing phosgene cooled to −5 ° C. at SV = 3 into a cylindrical container having a diameter of 55 mm and a height of 500 mm filled with the activated carbon (Yaikol S manufactured by Taihei Chemical Co., Ltd.). A thing was used.
[0049]
In the pipe reactor, the temperature rose to 60 ° C, but was 35 ° C at the outlet due to external cooling. The reaction mixture was allowed to stand and separate into an aqueous phase and an oil phase. 33 kg of the obtained oil phase was fractionated and charged into a reaction vessel with an internal volume of 200 liters equipped with a Faudler blade.
Next, 4.8 kg of methylene chloride and 33 kg of water were added thereto, and after cooling to 3 ° C. with stirring in a nitrogen atmosphere, pyridine hydrochloride was added as a catalyst in a proportion of 0.20 mol% with respect to bisphenol A. 5.41 kg of 25% aqueous sodium hydroxide solution was added and a polymerization reaction was carried out for 60 minutes with stirring at 420 rpm and a polycarbonate resin was produced. At this time, the internal temperature of the polymerization rose to 11 ° C.
[0050]
To this reaction mixture, 35 kg of methylene chloride and 10 kg of water were added, stirred for 20 minutes at room temperature, and allowed to stand to separate the aqueous phase and the organic phase. To the organic phase, 28 kg of 0.1N hydrochloric acid was added and stirred for 15 minutes, and then allowed to stand to separate the aqueous phase and the organic phase. As a result of repeating the washing operation of adding 28 kg of pure water to this organic phase and stirring for 15 minutes and then allowing it to stand to separate into an aqueous phase and an oil phase, chlorine ions were no longer detected in the aqueous phase. The washing operation was stopped. From the organic phase, methylene chloride was removed by evaporation with a kneader, and the resulting powder was dried to obtain a polycarbonate resin. Table 1 shows polymerization conditions and physical properties of the obtained polycarbonate resin.
[0051]
[Production Example 4]
In Production Example 3, a polycarbonate resin was produced in the same manner as in Production Example 3, except that the number of stirring rotations during the polymerization reaction was changed to 430 rpm. Table 1 shows the physical properties of the obtained polycarbonate resin.
[0052]
[Production Example 5]
2,2-bis (3-methyl-4-hydroxyphenyl) propane (hereinafter referred to as “bisphenol C”) and 1,1-bis (4-hydroxyphenyl)-are added to an aqueous caustic soda solution in which hydrosulfite is dissolved. An aqueous solution in which 1-phenylethane (hereinafter referred to as “bisphenol P”) is dissolved at 35 ° C. and then cooled to 25 ° C. and methylene chloride cooled to 5 ° C. are continuously added to a stainless steel pipe having an inner diameter of 6 mm. The mixture was supplied and mixed, and the mixture was emulsified by passing through a homomixer (product of Tokushu Kika Co., Ltd., TK homomic line flow LF-500 type) to prepare an emulsion. The feed rates to the pipe were bisphenol C 8.11 kg / Hr, bisphenol P 8.20 kg / Hr, caustic soda 5.28 kg / Hr, water 101.8 kg / Hr, hydrosulfite 0.018 kg / Hr, and methylene chloride 68. 0 kg / Hr. The produced emulsion was passed through a pipe having an inner diameter of 6 mm and a PTFE pipe reactor having an inner diameter of 6 mm and a length of 34 m. Liquefied phosgene, cooled to 0 ° C. at the same time, was supplied to the pipe reactor at 6.3 kg / Hr for reaction to produce oligomers. The flow rate of the pipe reactor is 1.7 m / sec. The phosgene was purified by passing phosgene cooled to −5 ° C. at SV = 3 into a cylindrical container having a diameter of 55 mm and a height of 500 mm filled with the activated carbon (Yaikol S manufactured by Taihei Chemical Co., Ltd.). Things were used.
[0053]
In the pipe reactor, the temperature rose to 60 ° C, but was 35 ° C at the outlet due to external cooling. The reaction mixture was allowed to stand and separate into an aqueous phase and an oil phase. From the obtained oil phase, 32 kg was collected and charged into a reaction vessel with a fouler blade having an internal volume of 200 liters.
Next, 11.5 kg of methylene chloride and 30 kg of water were added thereto, and after cooling to 3 ° C. with stirring in a nitrogen atmosphere, pyridine hydrochloride was added as a catalyst at a ratio of 0.02 mol% with respect to bisphenol A. 4.65 kg of 25% caustic soda aqueous solution was added and a polymerization reaction was carried out for 60 minutes while stirring at a stirring speed of 390 rpm to produce a polycarbonate resin. At this time, the internal temperature of the polymerization rose to 10 ° C.
[0054]
To this reaction mixture, 35 kg of methylene chloride and 10 kg of water were added, stirred for 20 minutes at room temperature, and allowed to stand to separate the aqueous phase and the organic phase. To the organic phase, 28 kg of 0.1N hydrochloric acid was added and stirred for 15 minutes, and then allowed to stand to separate the aqueous phase and the organic phase. As a result of repeating the washing operation of adding 28 kg of pure water to this organic phase and stirring for 15 minutes and then allowing it to stand to separate into an aqueous phase and an oil phase, chlorine ions were no longer detected in the aqueous phase. The washing operation was stopped. The methylene chloride was removed by evaporation from the organic phase with a kneader, and the resulting powder was dried to obtain a polycarbonate resin. Table 1 shows polymerization conditions and physical properties of the obtained polycarbonate resin.
[0055]
[Production Example 6]
Manufactured in Production Example 2 except that para-t-butylphenol was used at 2.4 mol% with respect to bisphenol A as a terminal terminator and triethylamine was used at 1.15 mol% with respect to bisphenol A as a catalyst during the polymerization reaction. A polycarbonate resin was produced in exactly the same manner as in Example 2. Table 2 shows the polymerization conditions and the physical properties of the obtained polycarbonate resin.
[0056]
[Production Example 7]
In Production Example 2, production was performed except that para-t-butylphenol was used at 1.6 mol% with respect to bisphenol A as a terminal terminator and triethylamine was used at 1.15 mol% with respect to bisphenol A as a catalyst during the polymerization reaction. A polycarbonate resin was produced in exactly the same manner as in Example 2. Table 2 shows the polymerization conditions and the physical properties of the obtained polycarbonate resin.
[0057]
[Production Example 8]
Production Example 3 except that para-t-butylphenol was used at 1.8 mol% with respect to bisphenol Z as a terminal terminator, and triethylamine was used at 1.15 mol% with respect to bisphenol Z as a catalyst during the polymerization reaction. A polycarbonate resin was produced in exactly the same manner as in Example 3. Table 2 shows the polymerization conditions and the physical properties of the obtained polycarbonate resin.
[0058]
[Production Example 9]
Production Example 3 except that para-t-butylphenol was used at 1.6 mol% with respect to bisphenol Z as a terminal terminator and triethylamine was used at 1.15 mol% with respect to bisphenol Z as a catalyst during the polymerization reaction. A polycarbonate resin was produced in exactly the same manner as in Example 3. Table 2 shows the polymerization conditions and the physical properties of the obtained polycarbonate resin.
[0059]
[Production Example 10]
Manufactured in Production Example 5 except that para-t-butylphenol was used at 1.7 mol% with respect to bisphenol Z as a terminal terminator and triethylamine was used at 1.15 mol% with respect to bisphenol Z as a catalyst during the polymerization reaction. A polycarbonate resin was produced in exactly the same manner as in Example 5. Table 2 shows the polymerization conditions and the physical properties of the obtained polycarbonate resin.
[0060]
[Table 1]

[0061]
[Table 2]

[0062]
<Preparation of dispersion for charge generation layer>
<Preparation of dispersion for undercoat layer>
Titania treated with 3% by weight of methyldimethoxysilane on titanium oxide (Ishihara Sangyo Co., Ltd .: trade name: TTO55N (average primary particle size: about 40 nm)) in a mixed solvent of methanol / n-propanol = 7/3 by a ball mill. The titanium oxide slurry is mixed with a copolymerized polyamide solution of the following structural formula (1), further subjected to ultrasonic dispersion treatment, and the solvent composition is methanol / n-propanol = 7/3. A dispersion having a solid content concentration of 16% by weight with titanium / polyamide = 3/1 was prepared to prepare an undercoat layer dispersion.
[0063]
[Chemical 1]

[0064]
Black angle (2θ ± 0.2) 9.3 °, 10.6 °, 13.2 °, 15.1 °, 15.7 °, 16.1 °, 20.8 ° in X-ray diffraction by CuKα ray 10 parts of oxytitanium phthalocyanine showing a strong diffraction peak at 23.3 °, 26.3 ° and 27.1 ° are added to 150 parts of 1,2-dimethoxyethane, and pulverized and dispersed in a sand grind mill. A pigment dispersion was prepared.
[0065]
5 parts of polyvinyl butyral (trade name Denkabutyral # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.) was dissolved in 95 parts of 1,2-dimethoxyethane to prepare a binder solution 1 having a solid content concentration of 5%.
5 parts of a phenoxy resin (trade name PKHH, manufactured by Union Carbide) was dissolved in 95 parts of 1,2-dimethoxyethane to prepare a binder solution 2 having a solid content concentration of 5%.
To 160 parts of the pigment dispersion prepared earlier, 50 parts of binder solution 1, 50 parts of binder solution 2, an appropriate amount of 1,2-dimethoxyethane and an appropriate amount of 4-methoxy-4-methylpentanone-2 were added. A dispersion α for charge generation layer having a solid content concentration of 4.0% and 1,2-dimethoxyethane: 4-methoxy-4-methylpentanone-2 = 9: 1 was prepared.
[0066]
10 parts of oxytitanium phthalocyanine, which shows the maximum diffraction peak at a Bragg angle (2θ ± 0.2) of 27.3 ° in X-ray diffraction using CuKα rays, is added to 150 parts of 1,2-dimethoxyethane and pulverized in a sand grind mill. Dispersion treatment was performed to prepare a pigment dispersion.
A binder solution 100 having a solid content concentration of 5% was prepared by dissolving 5 parts of polyvinyl butyral (trade name Denkabutyral # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.) in 95 parts of 1,2-dimethoxyethane in 160 parts of this pigment dispersion. Part, an appropriate amount of 1,2-dimethoxyethane and an appropriate amount of 4-methoxy-4-methylpentanone-2, and a solid content concentration of 4.0%, 1,2-dimethoxyethane: 4-methoxy-4-methyl A dispersion β1 for charge generation layer of pentanone-2 = 9: 1 was prepared.
Bragg angles (2θ ± 0.2) 9.3 °, 10.6 °, 13.2 °, 15.1 °, 15.7 °, 16.1 °, 20.8 ° in X-ray diffraction by CuKα ray 10 parts of oxytitanium phthalocyanine showing a strong diffraction peak at 23.3 °, 26.3 ° and 27.1 ° are added to 150 parts of 1,2-dimethoxyethane, and pulverized and dispersed in a sand grind mill. A pigment dispersion was prepared.
A binder solution 100 having a solid content concentration of 5% was prepared by dissolving 5 parts of polyvinyl butyral (trade name Denkabutyral # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.) in 95 parts of 1,2-dimethoxyethane in 160 parts of this pigment dispersion. Part, an appropriate amount of 1,2-dimethoxyethane and an appropriate amount of 4-methoxy-4-methylpentanone-2, and a solid content concentration of 4.0%, 1,2-dimethoxyethane: 4-methoxy-4-methyl A dispersion β2 for charge generation layer of pentanone-2 = 9: 1 was prepared.
Charge generation layer dispersion β1 and charge generation layer dispersion β2 were mixed at a ratio of 8: 2 to prepare charge generation layer dispersion β.
[0067]
<Production of photoconductor>
Example 1
The surface of a cylinder made of an aluminum alloy with an outer diameter of 30 mm, a length of 285 mm, and a wall thickness of 1.0 mm is mirror-finished, and then anodized, and then sealed with a sealant mainly composed of nickel acetate. As a result, an anodic oxide coating (alumite coating) of about 6 μm was formed. This cylinder was dip-coated in the charge generation layer dispersion α prepared earlier, and the weight after drying was 0.3 g / m.²The charge generation layer was formed so as to have a film thickness of about 0.3 μm.
Next, the cylinder in which this charge generation layer was formed was prepared by using 50 parts of the charge transporting compound represented by the following structural formula (2) and the polycarbonate resin (viscosity average molecular weight of about 30) produced in Production Example 1 as a binder resin for the charge transport layer. , 900, Mw / Mn = 1.34, Mv / Mn ′ = 1.15) 100 parts, silicone oil (trade name KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.05 parts tetrahydrofuran: 1,4-dioxane = 65: A charge transport layer having a thickness of 20 μm after drying was provided by dip coating in a solution dissolved in 35 mixed solvent. The photoreceptor drum thus obtained is designated as A1.
[0068]
[Chemical formula 2]

[0069]
Example 2
A photoconductor A2 was obtained in the same manner as in Example 1 except that the polycarbonate resin prepared in Production Example 2 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 42,200, Mw / Mn = 1.32, and Mv / Mn ′ = 1.10.
Comparative Example 1
A photoreceptor B1 was obtained in the same manner as in Example 1 except that the polycarbonate resin prepared in Production Example 6 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 30,200, Mw / Mn = 3.02, Mv / Mn ′ = 1.45.
Comparative Example 2
A photoconductor B2 was obtained in the same manner as in Example 1 except that the polycarbonate resin prepared in Production Example 7 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 45,900, Mw / Mn = 3.55, and Mv / Mn ′ = 1.51.
[0070]
Example 3
A cylinder made of an aluminum alloy with an outer diameter of 30 mm, a length of 254 mm, and a wall thickness of 0.75 mm, which has a mirror-finished surface, is dip-coated in the previously prepared dispersion for the undercoat layer, and the film thickness is about 1.3 μm below. A pulling layer was formed. The cylinder was immersed in the charge generation layer dispersion β prepared earlier, and the weight after drying was 0.3 g / m.²The charge generation layer was formed so as to have a film thickness of about 0.3 μm.
Next, the cylinder on which this charge generation layer was formed was prepared by using 50 parts of the charge transporting compound represented by the structural formula (2) and the polycarbonate resin (viscosity average molecular weight of about 30) produced in Production Example 1 as a binder resin for the charge transport layer. , 900, Mw / Mn = 1.34, Mv / Mn ′ = 1.15) 100 parts, silicone oil (trade name KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.05 parts tetrahydrofuran: 1,4-dioxane = 65: A charge transport layer having a thickness of 25 μm after drying was provided by dip coating in a solution dissolved in 35 mixed solvent. The photoreceptor drum thus obtained is designated as A3.
[0071]
Example 4
A photoconductor A3 was obtained in the same manner as in Example 3 except that the polycarbonate resin prepared in Production Example 2 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 42,200, Mw / Mn = 1.32, and Mv / Mn ′ = 1.10.
Comparative Example 3
A photoconductor B3 was obtained in the same manner as in Example 3 except that the polycarbonate resin prepared in Production Example 6 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 30,200, Mw / Mn = 3.20, and Mv / Mn ′ = 1.45.
Comparative Example 4
A photoconductor B4 was obtained in the same manner as in Example 3 except that the polycarbonate resin prepared in Production Example 7 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 45,900, Mw / Mn = 3.55, and Mv / Mn ′ = 1.51.
[0072]
Example 5
The surface of a cylinder made of an aluminum alloy with an outer diameter of 30 mm, a length of 285 mm, and a wall thickness of 1.0 mm is mirror-finished, and then anodized, and then sealed with a sealant mainly composed of nickel acetate. As a result, an anodic oxide coating (alumite coating) of about 6 μm was formed. This cylinder was dip-coated in the charge generation layer dispersion α prepared earlier, and the weight after drying was 0.3 g / m.²The charge generation layer was formed so as to have a film thickness of about 0.3 μm.
Next, 50 parts of the charge transporting compound represented by the structural formula (2) and the polycarbonate resin prepared in Production Example 3 as a binder resin for the charge transport layer (viscosity average molecular weight of about 41) were formed on the cylinder on which the charge generation layer was formed. , 900, Mw / Mn = 1.39, Mv / Mn ′ = 1.04), 100 parts of silicone oil (trade name KF96, manufactured by Shin-Etsu Chemical Co., Ltd.), 0.05 parts, mixed solvent of tetrahydrofuran: toluene = 80: 20 A charge transport layer having a thickness of 20 μm after drying was provided by dip coating in the solution dissolved in the solution. The photoreceptor drum thus obtained is designated as A5.
[0073]
Example 6
A photoreceptor A6 was obtained in the same manner as in Example 5 except that the polycarbonate resin prepared in Production Example 4 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 52,900, Mw / Mn = 1.38, and Mv / Mn ′ = 1.04.
Comparative Example 5
A photoconductor B5 was obtained in the same manner as in Example 5 except that the polycarbonate resin prepared in Production Example 8 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 46,800, Mw / Mn = 3.62, Mv / Mn ′ = 1.52.
Comparative Example 6
A photoconductor B6 was obtained in the same manner as in Example 5 except that the polycarbonate resin prepared in Production Example 9 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 56,900, Mw / Mn = 3.89, and Mv / Mn ′ = 1.54.
[0074]
Example 7
A cylinder made of an aluminum alloy with an outer diameter of 30 mm, a length of 254 mm, and a wall thickness of 0.75 mm, which has a mirror-finished surface, is dip-coated in the previously prepared dispersion for the undercoat layer, and the film thickness is about 1.3 μm below. A pulling layer was formed. This cylinder is immersed in the previously prepared dispersion for charge generation layer, and the weight after drying is 0.3 g / m.²The charge generation layer was formed so as to have a film thickness of about 0.3 μm.
Next, 50 parts of the charge transporting compound represented by the structural formula (2) and the polycarbonate resin prepared in Production Example 3 as a binder resin for the charge transport layer (viscosity average molecular weight of about 41) were formed on the cylinder on which the charge generation layer was formed. , 900, Mw / Mn = 1.39, Mv / Mn ′ = 1.04), 100 parts of silicone oil (trade name KF96, manufactured by Shin-Etsu Chemical Co., Ltd.), 0.05 parts, mixed solvent of tetrahydrofuran: toluene = 80: 20 A charge transport layer having a thickness of 25 μm after drying was provided by dip-coating in the solution dissolved in the solution. The photoreceptor drum thus obtained is designated as A7.
[0075]
Example 8
A photoconductor A8 was obtained in the same manner as in Example 7 except that the polycarbonate resin prepared in Production Example 4 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 52,900, Mw / Mn = 1.38, and Mv / Mn ′ = 1.04.
Comparative Example 7
A photoconductor B7 was obtained in the same manner as in Example 7 except that the polycarbonate resin prepared in Production Example 8 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 46,800, Mw / Mn = 3.62, Mv / Mn ′ = 1.52.
Comparative Example 8
A photoconductor B8 was obtained in the same manner as in Example 7 except that the polycarbonate resin prepared in Production Example 9 was used as the binder resin for the charge transport layer. This polycarbonate resin has Mv = 56,900, Mw / Mn = 3.89, and Mv / Mn ′ = 1.54.
[0076]
<Evaluation of photoreceptor>
[Electrical characteristics evaluation]
Next, the photoconductors A1 to A8 and B1 to B8 were mounted on a photoconductor characteristic tester (manufactured by Mitsubishi Chemical Corporation), and an electric characteristic evaluation test was performed by a cycle of charging, exposure, potential measurement, and static elimination. . The initial surface potential was -700V, and the exposure was carried out using a halogen lamp with a monochromatic light of 780 nm using an interference filter, and the exposure amount required to halve the surface potential from -700V to -350V (half exposure amount) , E1 / 2), 4.7 μJ / cm²(In the case of a photoreceptor produced using the dispersion α for charge generation layer, the time from exposure to potential measurement is about 390 ms) or 1.2 μJ / cm²(In the case of a photoreceptor produced using the dispersion β for charge generation layer, the time from exposure to potential measurement is about 100 ms) The surface potential (VL) at the time of irradiation was measured. Moreover, the residual electric potential (Vr) after neutralization light irradiation was measured using 660 nm LED light for static elimination light. The measurement was performed in an environment of temperature 25 ° C. and humidity 50% RH. The results are shown in Table 3.
[0077]
[Table 3]

[0078]
As shown in Table 3, the photoconductors A1 to A8 of the example have the same or better electrical characteristics than the photoconductors B1 to B8 of the comparative example.
[Measurement of film reduction by printing test]
Next, the photoconductors A1, A2, B1, B2, A5, A6, B5, and B6 are mounted on a commercially available color laser printer (LP3000C manufactured by Epson Corporation), and 24,000 sheets in monochrome (black) mode in a normal temperature and humidity environment. Printed out.
At this time, the film thickness of the photosensitive layer before printing and the film thickness after printing 24,000 sheets were measured, and the amount of film reduction per 10,000 printed sheets was calculated. The results are shown in Table 4.
Further, FIG. 1 and FIG. 2 are plots in which the Mv of the binder resin used is plotted on the horizontal axis and the amount of film loss per 10,000 is plotted on the vertical axis.
In addition, the photoconductors A3, A4, B3, B4, A7, A8, B7, and B8 are commercially available monochrome laser printers (manufactured by Lexmark, Optra S2450, 24 sheets per minute with A4 vertical feed, DC charging roller charging, rollers 30,000 sheets were printed at room temperature and humidity. The amount of film reduction per 10,000 sheets was calculated from the difference in film thickness before and after printing. The results are shown in Table 5.
Further, FIG. 3 and FIG. 4 show plots in which the Mv of the binder resin used is plotted on the horizontal axis and the amount of film loss per 10,000 is plotted on the vertical axis.
[0079]
[Table 4]

[0080]
[Table 5]

[0081]
【The invention's effect】
Since the polycarbonate of the present invention is superior in abrasion resistance compared to conventionally used polycarbonate, it is suitable for applications requiring heat resistance and high surface hardness. Further, by using the polycarbonate of the present invention in an electrophotographic photoreceptor, excellent electrical characteristics can be exhibited, and the abrasion resistance of the photoreceptor surface can be remarkably improved.
[Brief description of the drawings]
FIG. 1 Viscosity average molecular weight and film loss
Fig. 2 Viscosity average molecular weight and film loss
Fig. 3 Viscosity average molecular weight and film loss
[Figure 4] Viscosity average molecular weight and film loss

Claims (3)

In an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, the binder resin of the photosensitive layer is
A polycarbonate resin produced by reacting a carbonate-forming compound and a dihydroxy compound to produce an oligomer, and polymerizing the oligomer in the presence of a catalyst ,
A salt of a compound having a basicity of 7 or less as the pKa value of hydrochloride is used as the catalyst,
The ratio (Mw / Mn) of polystyrene-equivalent weight average molecular weight (Mw) and number average molecular weight (Mn) measured by gel permeation chromatography in the polycarbonate resin is 2.4 or less,
And a polycarbonate resin having a ratio (Mv / Mn ′) of 1.4 or less of the viscosity average molecular weight (Mv) calculated by the following formula (I) and the number average molecular weight (Mn ′) calculated from the number of molecular terminals. an electrophotographic photosensitive member, characterized in that.

(Wherein ηsp is the specific viscosity measured at 20 ° C. for a methylene chloride solution of polycarbonate resin, and C is the concentration of this methylene chloride solution. The methylene chloride solution has a polycarbonate resin concentration of 0.6 g / dl. Is used) The electrophotographic photoreceptor according to claim 1, wherein the catalyst is a salt of a nitrogen-containing heterocyclic compound . The polycarbonate resin, electrophotographic photosensitive member according to claim 1 or 2, characterized in that a polycarbonate resin produced by an interfacial polymerization reaction.

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