JP4204451B2 - Image forming apparatus and process cartridge for image forming apparatus - Google Patents

Description

  The present invention relates to a method for producing a coating solution for forming a photosensitive layer of an electrophotographic photoreceptor, a coating solution for forming a photosensitive layer produced by the production method, and an electrophotographic photoreceptor using the coating solution for forming a photosensitive layer. And an image forming apparatus including the electrophotographic photosensitive member, an image forming method, and a process cartridge for the image forming apparatus.

  In an image forming apparatus such as a copying machine, a printer, and a facsimile machine using an electrophotographic system, a uniformly charged photosensitive member is irradiated with writing light modulated by image data, and the photosensitive member is irradiated on the photosensitive member. An electrostatic latent image is formed, and toner is supplied from a developing unit to the photoconductor on which the electrostatic latent image is formed, and a toner image is formed on the photoconductor and developed. The image forming apparatus transfers the toner image on the photoconductor to the transfer paper (recording paper) by the transfer unit, and then fixes the toner transferred on the transfer paper by the fixing unit by heating and pressurizing, and remains on the surface of the photoconductor. The collected toner is collected by a method such as scraping with a cleaning blade at the cleaning unit.

  In an image forming apparatus using such an electrophotographic method, it has been known that, by reducing the coefficient of friction on the surface of the photoreceptor, unnecessary toner adhesion can be prevented and an image free of background stains can be obtained. It has been. In addition, a photoreceptor having a small surface friction coefficient can reduce the amount of surface wear and extend the life of the photoreceptor.

  That is, the reason for determining the life of the photoconductor is the wear of the photoconductive layer of the photoconductor. When a certain amount of the photoconductive layer is scraped off, the electrical characteristics of the photoconductor change and an appropriate image forming process can be performed. Disappear. This friction is generated in all the parts where the photoconductor and other image forming units such as the developing unit and the transfer unit are in contact with each other in the image forming process described above. It is possible to reduce the wear generated at the site and improve the life of the photoreceptor.

  Further, it is known that by reducing the coefficient of friction on the surface of the photoconductor, the transfer rate when the toner image formed on the photoconductor is transferred to the transfer target is improved. That is, since it is possible to suppress worm-engraving prints and to reduce the amount of residual toner after transfer, there are also effects such as reduction of the amount of waste toner.

Furthermore, recently, due to the demand for higher image quality in electrophotography, spherical toners produced using emulsion polymerization methods, suspension polymerization methods, etc. can be highly effective apart from the point of cleaning efficiency. It has become clear.
In general, for cleaning the transfer residual toner on the photosensitive member, a method is employed in which a blade formed of urethane rubber or the like is brought into contact with the counter direction and the toner is removed by the blade. However, since the spherical toner is rubbed into the contact portion between the cleaning blade and the photosensitive member and slips through, the cleaning toner often causes poor cleaning. The reason for this is that when the spherical toner is to be removed from the surface of the photoreceptor using the cleaning blade described above, the toner is close to the closest packed state at the cleaning nip, which is the contact portion between the surface of the photoreceptor and the cleaning blade. The toner slips between the first layer toner having strong adhesion to the surface of the photoreceptor and the second layer toner on the surface layer, and the first layer toner passes through the blade, resulting in poor cleaning. End up. On the other hand, it can be considered that by reducing the coefficient of friction on the surface of the photoreceptor, slipping of the spherical toner can be suppressed, and defective cleaning can be suppressed.

As a method for reducing the friction coefficient on the surface of the photoreceptor, it has been proposed to add a lubricant that reduces the friction coefficient to the surface layer of the photoreceptor. Specifically, there are those proposed in Patent Documents 1 and 2 and the like.
Lubricants include fluorine atom-containing resins such as polytetrafluoroethylene (hereinafter referred to as fluororesins), spherical acrylic resins, polyethylene resins, metal oxide powders such as silicon oxide and aluminum oxide, and zinc stearate. Lubricating liquids such as metal soap powder and silicone oil are known. These are dispersed in a binder resin such as an acrylic resin, a polyester resin, a polyurethane resin, or a polycarbonate resin, and then formed as a surface layer or a protective layer of the photoreceptor.
However, in general, such an additive affects the electrical characteristics of the electrophotographic photosensitive member, and often causes side effects such as an increase in residual potential and image blur in a high temperature and high humidity environment. Therefore, in order to suppress such side effects, it is necessary to limit the amount added, and as a result, sufficient lubricity cannot be obtained, and in particular, there is a problem that a low friction coefficient cannot be maintained by long-term use. It has occurred. In addition, since many of the lubricants have self-destructive characteristics, the layer containing the lubricant has weak mechanical strength, and there are problems such as deterioration of the durability of the photoreceptor due to a decrease in wear resistance. Likely to happen.

  As another method for reducing the coefficient of friction on the surface of the photoconductor, as proposed in Patent Document 3, an image forming apparatus having a mechanism for supplying a lubricant to the surface of the photoconductor is conventionally proposed. It has been put into practical use. However, if the supply amount of the lubricant is insufficient, there is a problem that a sufficiently low friction coefficient cannot be obtained. In addition, increasing the supply amount shortens the life of the lubricant as a consumable item, leading to deterioration of maintainability, and failure caused by excessive lubricant, for example, changes in the electrical characteristics of the photoreceptor surface. In some cases, image blurring or background stains may occur.

  In addition to these conventional techniques, many proposals have been made to reduce the friction coefficient of the electrophotographic photosensitive member surface. However, the improvement of the cleaning property by lowering the friction coefficient of the photosensitive member surface and the improvement of the durability of the photosensitive member. There has been a demand for further improvement since it has not yet satisfied the problems of long life and maintenance of image quality stability in repeated use over a long period of time.

JP-A-63-249152 JP 56-142567 A JP 58-102949 A

An object of the present invention is to solve the above-mentioned problems, maintain a low surface friction coefficient, have good electrophotographic characteristics, and perform highly stable image formation and cleaning over a long period of time. It is to provide a forming method.
Another object of the present invention is to provide such a process cartridge for an image forming apparatus.

Therefore, in order to achieve the above-mentioned problems, the present inventors diligently studied about reducing the friction coefficient of the electrophotographic photosensitive member surface and improving the durability.
The above-mentioned problem is (1) “in an image forming apparatus having at least an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit, and a transferring unit, and the electrophotographic photosensitive member generates at least a charge on a conductive support. An electrophotographic photosensitive member having a layer containing a substance and a charge transporting substance, the outermost surface layer having the following general formula (1);

〔式中のＲ^１、Ｒ^２及びＲ^３は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｙはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基、Ｚ^１及びＺ^２は、それぞれ同一又は異なる水素原子、低級アルキル基又は

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

基（Ｒ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である）、ｍは１０，０００以下の正の整数、ｎは１以上の整数である〕
で表わされるポリオルガノシロキサンと、下記一般式（２）；

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2):

（式中のＲ^７は水素原子又はメチル基、Ｒ^８はアルキル基、アルコキシ置換アルキル基、シクロアルキル基又はアリール基である）
で表わされる（メタ）アクリル酸エステル又はこの（メタ）アクリル酸エステル７０重量％以上と共重合可能な単量体３０重量％以下との混合物とを、重量比５：９５ないし９５：５の割合で乳化グラフト共重合させて成るアクリル変性ポリオルガノシロキサンであり、しかもＮａイオン含有量が１００ｐｐｍ以下、Ｓイオン含有量が２００ｐｐｍ以下に精製したものを含有し、かつ該画像形成装置が電子写真感光体表面に潤滑性付与剤を塗布する機構を備えていることを特徴とする画像形成装置」、（２）「前記最表層中に含有するアクリル変性ポリオルガノシロキサンの含有量が５重量％〜５０重量％であることを特徴とする前記第（１）項に記載の画像形成装置」、（３）「前記最表層中にバインダー樹脂、電荷輸送性物質を含有することを特徴とする前記第（１）項又は第（２）項に記載の画像形成装置」、（４）「前記潤滑性付与剤が、金属石鹸であることを特徴とする前記第（１）項乃至第（３）項のいずれかに記載の画像形成装置」、（５）「前記潤滑性付与剤として、ステアリン酸亜鉛、ステアリン酸アルミニウム、ステアリン酸カルシウムより選ばれる金属石鹸を、単独または２種類以上混合して用いることを特徴とする前記第（１）項乃至第（４）項のいずれかに記載の画像形成装置」、（６）「前記画像形成装置が複数の電子写真感光体、帯電手段、現像手段、転写手段を有するタンデム型であることを特徴とする前記第（１）項乃至第（５）項のいずれかに記載の画像形成装置」、（７）「前記画像形成装置が電子写真感光体上に現像されたトナー画像を中間転写体上に一次転写したのち、該中間転写体上のトナー画像を記録材上に二次転写する中間転写手段を有する画像形成装置であって、複数色のトナー画像を中間転写体上に順次重ね合わせてカラー画像を形成し、該カラー画像を記録材上に一括で二次転写することを特徴とする前記第（１）項乃至第（６）項のいずれかに記載の画像形成装置」によって解決される。
また、上記課題は、本発明の（８）「少なくとも電子写真感光体を有する画像形成装置を用い、少なくとも帯電工程、露光工程、現像工程及び転写工程を有する画像形成方法において、該電子写真感光体が導電性支持体上に少なくとも電荷発生物質と電荷輸送物質を含む層を有する電子写真感光体であって、その最表面層に下記一般式（１）；

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. An image forming apparatus comprising a mechanism for applying a lubricity-imparting agent to the surface ", (2)" The content of the acrylic-modified polyorganosiloxane contained in the outermost layer is 5 wt% to 50 wt% %. The image forming apparatus according to item (1) above, wherein (3) “the outermost layer contains a binder resin and a charge transporting substance” The image forming apparatus according to item (1) or (2) ”, (4)“ The lubricity-imparting agent is metal soap, ”(1) The image forming apparatus according to any one of items 1 to 3), (5) “as the lubricity imparting agent, one or two kinds of metal soaps selected from zinc stearate, aluminum stearate, and calcium stearate. The image forming apparatus according to any one of (1) to (4) above, wherein the image forming apparatus includes a plurality of electrophotographic photosensitive members, charging The image forming apparatus according to any one of (1) to (5) above, wherein the image forming apparatus is a tandem type having a means, a developing means, and a transfer means. Toner image developed on electrophotographic photoreceptor An image forming apparatus having an intermediate transfer unit that performs primary transfer onto an intermediate transfer member and then secondary transfer of a toner image on the intermediate transfer member onto a recording material, wherein a plurality of color toner images are placed on the intermediate transfer member. The image forming apparatus according to any one of (1) to (6), wherein a color image is formed by sequentially superimposing and the color image is secondarily transferred onto a recording material at once. Is solved by.
In addition, the above-described problem is solved by (8) “ an image forming apparatus having at least an electrophotographic photosensitive member and having at least a charging step, an exposure step, a developing step, and a transfer step. Is an electrophotographic photosensitive member having a layer containing at least a charge generating material and a charge transporting material on a conductive support, and the following general formula (1):

〔式中のＲ^１、Ｒ^２及びＲ^３は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｙはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基、Ｚ^１及びＺ^２は、それぞれ同一又は異なる水素原子、低級アルキル基又は

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

基（Ｒ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である）、ｍは１０，０００以下の正の整数、ｎは１以上の整数である〕
で表わされるポリオルガノシロキサンと、下記一般式（２）；

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2):

（式中のＲ^７は水素原子又はメチル基、Ｒ^８はアルキル基、アルコキシ置換アルキル基、シクロアルキル基又はアリール基である）
で表わされる（メタ）アクリル酸エステル又はこの（メタ）アクリル酸エステル７０重量％以上と共重合可能な単量体３０重量％以下との混合物とを、重量比５：９５ないし９５：５の割合で乳化グラフト共重合させて成るアクリル変性ポリオルガノシロキサンであり、しかもＮａイオン含有量が１００ｐｐｍ以下、Ｓイオン含有量が２００ｐｐｍ以下に精製したものを含有し、かつ該画像形成装置が電子写真感光体表面に潤滑性付与剤を塗布する機構を備えていることを特徴とする画像形成方法」、（９）「前記最表層中に含有するアクリル変性ポリオルガノシロキサンの含有量が５重量％〜５０重量％であることを特徴とする前記第（８）項に記載の画像形成方法」、（１０）「前記最表層中にバインダー樹脂、電荷輸送性物質を含有することを特徴とする前記第（８）項又は第（９）項に記載の画像形成方法」、（１１）「前記潤滑性付与剤が、金属石鹸であることを特徴とする前記第（８）項乃至第（１０）項のいずれかに記載の画像形成方法」、（１２）「前記潤滑性付与剤として、ステアリン酸亜鉛、ステアリン酸アルミニウム、ステアリン酸カルシウムより選ばれる金属石鹸を、単独または２種類以上混合して用いることを特徴とする前記第（８）項乃至第（１１）項のいずれかに記載の画像形成方法」、（１３）「前記画像形成方法が複数の電子写真感光体、帯電工程、現像工程、転写工程を有するタンデム型であることを特徴とする前記第（８）項乃至第（１２）項のいずれかに記載の画像形成方法」、（１４）「前記画像形成方法が電子写真感光体上に現像されたトナー画像を中間転写体上に一次転写したのち、該中間転写体上のトナー画像を記録材上に二次転写する中間転写工程を有する画像形成方法であって、複数色のトナー画像を中間転写体上に順次重ね合わせてカラー画像を形成し、該カラー画像を記録材上に一括で二次転写することを特徴とする前記第（８）項乃至第（１３）項のいずれかに記載の画像形成方法」によって解決される。
また、上記課題は、本発明の（１５）「前記電子写真感光体と、帯電手段、露光手段、現像手段、転写手段の少なくとも一つとを具備してなることを特徴とする前記第（１）項乃至第（７）項のいずれかに記載の画像形成装置用プロセスカートリッジ」によって解決される。

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. An image forming method comprising a mechanism for applying a lubricity-imparting agent to the surface ", (9)" The content of the acrylic-modified polyorganosiloxane contained in the outermost layer is 5 wt% to 50 wt% %. The image forming method according to item (8), characterized in that the binder resin and the charge transporting substance are contained in the outermost layer. The image forming method according to item (8) or (9) ”, (11)“ The lubricity-imparting agent is a metal soap ”(8) The image forming method according to any one of Items 1 to (10), (12) “As the lubricity-imparting agent, one or two kinds of metal soaps selected from zinc stearate, aluminum stearate, and calcium stearate are used. The image forming method according to any one of (8) to (11) above, wherein the image forming method comprises a plurality of electrophotographic photosensitive members, charging The image forming method according to any one of (8) to (12), wherein the image forming method is a tandem type having a process, a developing process, and a transfer process. Developed on electrophotographic photoreceptor An image forming method including an intermediate transfer step in which a toner image on the intermediate transfer member is first transferred onto an intermediate transfer member and then a toner image on the intermediate transfer member is secondarily transferred onto a recording material. Item (8) to Item (13), wherein a color image is formed by sequentially superimposing on a transfer member, and the color image is secondarily transferred collectively onto a recording material. The image forming method of the above.
Further, the above-described problem is (15) of the present invention, wherein the electrophotographic photosensitive member is provided with at least one of a charging unit, an exposure unit, a developing unit, and a transfer unit. This is solved by the process cartridge for an image forming apparatus according to any one of Items 1 to 7.

  In the image forming apparatus of the present invention having at least an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit, and a transferring unit, the electrophotographic photosensitive member includes at least a charge generating substance and a charge transporting substance on a conductive support. An electrophotographic photosensitive member having a layer, the outermost surface layer having the following general formula (1);

〔式中のＲ^１、Ｒ^２及びＲ^３は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｙはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基、Ｚ^１及びＺ^２は、それぞれ同一又は異なる水素原子、低級アルキル基又は

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

基（Ｒ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である）、ｍは１０，０００以下の正の整数、ｎは１以上の整数である〕
で表わされるポリオルガノシロキサンと、下記一般式（２）；

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2):

（式中のＲ^７は水素原子又はメチル基、Ｒ^８はアルキル基、アルコキシ置換アルキル基、シクロアルキル基又はアリール基である）
で表わされる（メタ）アクリル酸エステル又はこの（メタ）アクリル酸エステル７０重量％以上と共重合可能な単量体３０重量％以下との混合物とを、重量比５：９５ないし９５：５の割合で乳化グラフト共重合させて成るアクリル変性ポリオルガノシロキサンであり、しかもＮａイオン含有量が１００ｐｐｍ以下、Ｓイオン含有量が２００ｐｐｍ以下に精製したものを含有し、かつ該画像形成装置が電子写真感光体表面に潤滑性付与剤を塗布する機構を備えていることを特徴とする画像形成装置とすることで、感光体表面の低摩擦係数化によるクリーニング性の向上と、耐久性向上による感光体の長寿命化、長期間繰り返し使用における画質安定性の維持という課題を同時に達成することができた。
すなわち、本発明は、クリーニングが困難な、球形の重合トナーを用いても、クリーニング不良が発生せず、安定して良好な画像を出力できる画像家生成装置、画像形成方法、および、該画像形成装置用プロセスカートリッジが提供されるという、極めて優れた効果を奏するものである。

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. By providing a mechanism for applying a lubricity-imparting agent to the surface, it is possible to improve the cleaning property by lowering the coefficient of friction on the surface of the photoconductor and to increase the length of the photoconductor by improving the durability. At the same time, we were able to achieve the issues of longevity and maintenance of image quality stability in repeated use over a long period of time.
That is, the present invention provides an imager generating device, an image forming method, and an image forming method capable of stably outputting a good image without causing poor cleaning even when a spherical polymer toner that is difficult to clean is used. This provides an extremely excellent effect of providing a process cartridge for an apparatus.

Hereinafter, the present invention will be described in detail.
As described above, the present inventor, in an image forming apparatus having at least an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit, and a transferring unit, includes at least a charge generating material on a conductive support. An electrophotographic photosensitive member having a layer containing a charge transport material, the outermost surface layer having the following general formula (1);

〔式中のＲ^１、Ｒ^２及びＲ^３は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｙはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基、Ｚ^１及びＺ^２は、それぞれ同一又は異なる水素原子、低級アルキル基又は

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

基（Ｒ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である）、ｍは１０，０００以下の正の整数、ｎは１以上の整数である〕
で表わされるポリオルガノシロキサンと、下記一般式（２）；

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2):

（式中のＲ^７は水素原子又はメチル基、Ｒ^８はアルキル基、アルコキシ置換アルキル基、シクロアルキル基又はアリール基である）
で表わされる（メタ）アクリル酸エステル又はこの（メタ）アクリル酸エステル７０重量％以上と共重合可能な単量体３０重量％以下との混合物とを、重量比５：９５ないし９５：５の割合で乳化グラフト共重合させて成るアクリル変性ポリオルガノシロキサンであり、しかもＮａイオン含有量が１００ｐｐｍ以下、Ｓイオン含有量が２００ｐｐｍ以下に精製したものを含有し、かつ該画像形成装置が電子写真感光体表面に潤滑性付与剤を塗布する機構を備えていることを特徴とする画像形成装置とすることで、上記課題を解決することを見出し、本発明に至った。

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. It has been found that the above-mentioned problems can be solved by using an image forming apparatus having a mechanism for applying a lubricity-imparting agent to the surface.

That is, according to the present invention, the outermost layer is a specific acrylic-modified polyorganosiloxane having the above-described structure, and further contains a refined Na ion content of 100 ppm or less and an S ion content of 200 ppm or less , and By providing the image forming apparatus with a mechanism for applying a lubricity-imparting agent to the surface of the electrophotographic photosensitive member, the low coefficient of friction of the surface of the electrophotographic photosensitive member can be maintained even after repeated use over a long period of time. Since the wear of the photographic photosensitive member can be remarkably suppressed, the lifetime becomes very long. Furthermore, since the image forming apparatus of the present invention consumes less lubricity than the conventional one, the cost can be reduced and the maintenance can be greatly improved.

  By containing the specific acrylic-modified polyorganosiloxane, the friction coefficient on the surface of the electrophotographic photosensitive member is reduced, and as a result, the spherical polymerized toner, the pulverized toner having a reduced particle size, and the cleaning property of the polymerized toner are obtained. It is considered that abnormal images such as background stains due to poor cleaning can be suppressed. Furthermore, the lubricity imparting agent effectively works to maintain a low coefficient of friction, and contributes to maintenance of cleaning properties for repeated use over a long period of time and suppression of photoreceptor wear. Further, the reason why the wear of the lubricity imparting agent can be suppressed is not clearly understood, but the following may be considered.

  The surface of the photoreceptor containing the specific acrylic-modified polyorganosiloxane has a high affinity with the lubricity imparting agent and the applied lubricity imparting agent is difficult to peel off. Therefore, the lubricity imparting agent once applied stays on the surface of the photoreceptor for a long time, and exhibits an effect of reducing the friction coefficient. As a result, it is considered that wear of the lubricity imparting agent and wear of the photoreceptor are suppressed, and a lower friction coefficient is obtained by a synergistic effect with the lower friction coefficient of the acrylic-modified polyorganosiloxane.

According to the invention, in the photoreceptor used in the image forming apparatus, the content of the specific acrylic-modified polyorganosiloxane contained in the outermost layer is 5% by weight to 50% by weight. It is included as one of its more preferred embodiments.
By containing the specific acrylic-modified polyorganosiloxane within the above range, the effect of reducing the coefficient of friction on the surface of the photoreceptor, the long-term durability, and the leveling property of the coating film surface are also improved, and a highly durable photoreceptor can be obtained. Therefore, it is possible to obtain an image forming apparatus capable of outputting a higher quality image even when used repeatedly for a long time.

According to the invention, in the image forming apparatus, the outermost layer includes a binder resin and a charge transporting material as one of more preferable embodiments.
As a result, the charge transport capability of the outermost layer is improved, a good potential contrast is obtained, and a very sharp and high-quality image can be obtained.

According to the invention, in the image forming apparatus, the lubricity-imparting agent is a metal soap, and more preferably, a metal selected from zinc stearate, aluminum stearate, and calcium stearate as the lubricity-imparting agent. One of the more preferable embodiments is to use soap alone or in combination of two or more.
These lubricity-imparting agents can be used as powders, but can be melted and solidified to form rod-like solids, so that they are easy to handle, and the acrylic modified polyorgano is used on the outermost layer. Since the coating property on the surface of the electrophotographic photosensitive member containing siloxane is good, the friction coefficient is further reduced, so that the consumption of the lubricity imparting agent is suppressed, and further, the wear on the surface of the electrophotographic photosensitive member is also suppressed. It is.

According to the invention, the image forming apparatus and the image forming method are a tandem type having a plurality of electrophotographic photosensitive members, a charging unit, a developing unit, and a transfer unit, and / or the image forming apparatus is electrophotographic. An image forming apparatus having an intermediate transfer unit that primarily transfers a toner image developed on a photosensitive member onto an intermediate transfer member and then secondarily transfers the toner image on the intermediate transfer member onto a recording material. One of the more preferable embodiments includes forming a color image by sequentially superimposing color toner images on an intermediate transfer member, and then performing secondary transfer of the color image collectively onto a recording material. .
That is, by using the tandem type, it is possible to transfer toner images of a plurality of colors with a single sheet passing, so that a full color image can be output as fast as a monochrome image.

  Furthermore, since the surface of the photoconductor has a low friction coefficient, the toner transfer efficiency is high and the residual toner can be suppressed. Therefore, color mixing on the photoconductor is suppressed, and the toner recycling is very effective. . Furthermore, secondary transfer onto the transfer material via the intermediate transfer member facilitates the alignment of the toner images of multiple colors on the intermediate transfer member, and a good full-color image with reduced color misregistration can be obtained. The layout through the intermediate transfer member increases the degree of freedom of the layout in the image forming apparatus, and the image forming apparatus and the image forming method have achieved miniaturization of the apparatus and improvement in maintainability.

Furthermore, according to the present invention, there is provided a process cartridge for an image forming apparatus comprising at least one of a charging unit, an exposure unit, a developing unit, and a transfer unit and the electrophotographic photosensitive member of the present invention.
As a result, the electrophotographic photosensitive member and other process members can be easily replaced in a short time, so that the time required for maintenance can be shortened and the cost can be reduced. Further, since the process member and the electrophotographic photosensitive member are integrated, there are also advantages such as improvement in the accuracy of the mounting position.

  FIG. 1 is a schematic cross-sectional view of an electrophotographic photosensitive member used in the image forming apparatus of the present invention, and shows an electrophotographic photosensitive member having a configuration in which a photosensitive layer is provided on a conductive support. 2, 3 and 4 show other examples of the structure of the electrophotographic photosensitive member according to the present invention. FIG. 2 shows a function-separated type electrophotographic photoreceptor whose photosensitive layer is composed of a charge generation layer (CGL) and a charge transport layer (CTL), and FIG. 3 shows a conductive support and a function-separated type. An electrophotographic photosensitive member is shown in which an undercoat layer is inserted between CGL and CTL of the photosensitive layer. FIG. 4 shows an electrophotographic photosensitive member in which a protective layer is further formed on the photosensitive layer of the type shown in FIG. The electrophotographic photosensitive member according to the present invention may have other layers other than the above as long as it has at least a photosensitive layer on a conductive support, and the type of the photosensitive layer. May be combined arbitrarily.

The conductive support used in the electrophotographic photosensitive member in the present invention includes a conductor or an insulator subjected to a conductive treatment, for example, a metal such as Al, Ni, Fe, Cu, Au, or an alloy thereof, polyester A thin film made of a metal such as Al, Ag, Au or a conductive material such as In ₂ O ₃ or SnO ₂ on an insulating substrate such as polycarbonate, polyimide, or glass, carbon black, graphite, Al, A resin substrate obtained by uniformly dispersing a metal powder such as Cu or Ni, conductive glass powder or the like and imparting conductivity to the resin, paper subjected to conductive treatment, or the like can be used. The shape of the conductive support is not particularly limited, and any of a plate shape, a drum shape, or a belt shape can be used. However, when a belt-like support is used, it is necessary to provide a driving roller and a driven roller inside. While the equipment is complicated and large, there are advantages such as increased flexibility in layout. However, when forming a protective layer, there is a possibility that cracks called cracks may occur on the surface due to insufficient flexibility of the protective layer, which may cause granular background stains. It is done. For this reason, a drum-like member having high rigidity is preferably used as the support.

  If necessary, an undercoat layer may be provided between the conductive support and the photosensitive layer. Such an undercoat layer is provided for the purpose of improving adhesiveness, preventing moire, improving the coatability of the upper layer, and reducing residual potential. The undercoat layer generally contains a resin as a main component, but these resins are resins having high solubility resistance to general organic solvents in consideration of applying a photosensitive layer thereon with a solvent. It is desirable to be. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resins, alkyd-melamine resins, and epoxy resins. Examples thereof include curable resins that form a three-dimensional network structure. Further, fine powders such as metal oxides exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like, or metal sulfides and metal nitrides may be added. These undercoat layers can be formed by a common coating method using an appropriate solvent.

Further, as the undercoat layer, a metal oxide layer formed by using, for example, a sol-gel method using a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like is also useful.
In addition, as the undercoat layer, an anodized layer of Al ₂ O ₃ , an organic material such as polyparaxylylene (parylene), or an inorganic material such as SnO ₂ , TiO ₂ , ITO, or CeO ₂ is used. It may be provided by a vacuum thin film manufacturing method.
The thickness of the undercoat layer is suitably about 0.1 to 10 μm, more preferably 1 μm to 5 μm.

As the kind of the photosensitive layer used in the electrophotographic photosensitive member of the present invention, any of Se type, OPC type and the like can be applied. Examples of inorganic materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, and selenium-arsenic compounds. In particular, environmentally friendly and inexpensive OPC is good.
The photosensitive layer in the present invention may be either a single layer type or a laminated type, but here, a laminated type will be described. First, the charge generation layer will be described.
The charge generation layer is a layer mainly composed of a charge generation material, and a binder resin may be used as necessary. As the charge generation material, inorganic materials and organic materials can be used.

Examples of inorganic materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, and selenium-arsenic compounds.
On the other hand, a known material can be used as the organic material. For example, phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, azulenium salt pigments, squaric acid methine pigments, azo pigments having a carbazole skeleton, azo pigments having a triphenylamine skeleton, azo pigments having a diphenylamine skeleton, dibenzothiophene skeleton Azo pigments having fluorenone skeleton, azo pigments having oxadiazole skeleton, azo pigments having bis-stilbene skeleton, azo pigments having distyryl oxadiazole skeleton, azo pigments having distyrylcarbazole skeleton, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, Goido based pigments, and bisbenzimidazole pigments. These charge generation materials can be used alone or as a mixture of two or more.

As a binder resin used as necessary for the charge generation layer, polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, Polyacrylamide or the like is used. These binder resins can be used alone or as a mixture of two or more.
Moreover, you may add a charge transport substance as needed. In addition to the binder resin described above, a polymer charge transporting material is also preferably used as the binder resin for the charge generation layer.

Examples of the organic solvent used in the charge generation layer forming coating solution include acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, dichloroethane, dichloropropane, trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, Examples include dioxolane, dioxane, methanol, ethanol, isopropyl alcohol, butanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve, ethyl cellosolve, and propyl cellosolve. These organic solvents may be used alone or in combination of two or more. good.
In particular, tetrahydrofuran, methyl ethyl ketone, dichloromethane, methanol, and ethanol having a boiling point of 40 ° C. or higher and 80 ° C. or lower are preferably used because they can be easily dried after coating.

  The charge generation layer forming coating solution is produced by dispersing and dissolving a charge generation material and, if necessary, a binder resin in the organic solvent. Examples of the method for dispersing the organic pigment in the organic solvent include a dispersion method using a dispersion medium such as a ball mill, a bead mill, a sand mill, and a vibration mill, and a high-speed liquid collision dispersion method.

As a method for forming the charge generation layer, a vacuum thin film preparation method and a casting method from a solution dispersion system can be largely mentioned.
Examples of the former method include a glow discharge polymerization method, a vacuum deposition method, a CVD method, a sputtering method, a reactive sputtering method, an ion plating method, and an accelerated ion injection method. This vacuum thin film manufacturing method can satisfactorily form the inorganic material or organic material described above.
In order to provide the charge generation layer by the latter casting method, a charge generation layer forming coating solution is used and a conventional method such as dip coating, spray coating, or bead coating is used. it can.
The film thickness of the charge generation layer varies in electrophotographic characteristics, particularly photosensitivity, depending on the thickness, and generally the photosensitivity increases as the film thickness increases. Therefore, the film thickness of the charge generation layer needs to be set in a suitable range depending on the required specifications of the image forming apparatus. Generally, in order to obtain the sensitivity required for an electrophotographic photoreceptor, a film thickness of about 0.01 to 5 μm is appropriate, and preferably about 0.05 to 2 μm.

The charge transport layer is a layer intended to hold a charged charge and to couple the charge generated and separated in the charge generation layer by exposure to the charged charge that has been held. In order to achieve the purpose of holding the charged charge, it is required that the electric resistance is high. Further, in order to achieve the purpose of obtaining a high surface potential with the charged charge that has been held, it is required that the dielectric constant is small and the charge mobility is good.
The charge transport layer for satisfying these requirements is composed of a charge transport material and a binder resin used as necessary. Such a charge transport layer can be formed by dissolving or dispersing these charge transport materials and a binder resin in an appropriate solvent, and applying and drying them. If necessary, an appropriate amount of additives such as a plasticizer, an antioxidant, and a leveling agent can be added to the charge transport layer in addition to the charge transport material and the binder resin.

Examples of the charge transport material include a hole transport material and an electron transport material.
Examples of the electron transport material include chloroanil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2, 4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophene-4-one, 1,3,7-tri Examples thereof include electron accepting substances such as nitrodibenzothiophene-5,5-dioxide. These electron transport materials can be used alone or as a mixture of two or more.
Examples of the hole transporting material include the electron donating materials shown below and are used favorably. For example, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, 9- (p-diethylaminostyrylanthracene), 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline , Phenylhydrazones, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, phenazine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, thiophene derivatives, and the like. These hole transport materials can be used alone or as a mixture of two or more.

Further, the polymer charge transporting material may have the following structure.
(A) Polymer having carbazole ring For example, poly-N-vinylcarbazole, JP-A-50-82056, JP-A-54-9632, JP-A-54-11737, JP-A-4-175337 And the compounds described in JP-A-4-183719 and JP-A-6-234841.
(B) Polymer having a hydrazone structure For example, JP-A-57-78402, JP-A-61-20953, JP-A-61-296358, JP-A-1-134456, JP-A-1-134456 179164, JP-A-3-180851, JP-A-3-180852, JP-A-3-50555, JP-A-5-310904, JP-A-6-234840, and the like. Is done.
(C) Polysilylene polymer For example, JP-A 63-285552, JP-A-1-88461, JP-A-4-264130, JP-A-4-264131, JP-A-4-264132, Examples thereof include compounds described in Kaihei 4-264133 and JP-A-4-289867.
(D) Polymer having a triarylamine structure For example, N, N-bis (4-methylphenyl) -4-aminopolystyrene, JP-A-1-134457, JP-A-2-282264, JP-A-2- Examples include compounds described in JP-A-304456, JP-A-4-133605, JP-A-4-133066, JP-A-5-40350, and JP-A-5-202135.
(E) Other polymers For example, formaldehyde condensation polymer of nitropyrene, JP-A-51-73888, JP-A-56-150749, JP-A-6-234836, JP-A-6-234837 The described compounds and the like are exemplified.

The polymer having an electron donating group used in the present invention is not limited to the above-mentioned polymer, but also a copolymer of a known monomer, a block polymer, a graft polymer, a star polymer, It is also possible to use a cross-linked polymer having an electron donating group as disclosed in JP-A-3-109406.
Further, examples of polycarbonates, polyurethanes, polyesters, and polyethers having a triarylamine structure that are further useful as the polymer charge transporting material used in the present invention include, for example, JP-A 64-1728 and JP-A 64- 13061, JP 64-19049, JP 4-11627, JP 4-225014, JP 4-230767, JP 4-320420, JP 5-232727 JP, 7-56374, JP 9-127713, JP 9-222740, JP 9-265197, JP 9-211877, JP 9-304956. And the like.
Furthermore, as a binder resin that can be used in combination with the charge transport layer, for example, polycarbonate, polyester, methacrylic resin, acrylic resin, polyethylene, vinyl chloride, vinyl acetate, polystyrene, phenol resin, epoxy resin, polyurethane, polyvinylidene chloride, alkyd resin, Silicone resin, polyvinyl carbazole, polyvinyl butyral, polyvinyl formal, polyacrylate, polyacrylamide, phenoxy resin, and the like are used. These binder resins can be used alone or as a mixture of two or more.

The charge transport layer may be configured as a copolymer of a crosslinkable binder resin and a crosslinkable charge transfer material.
The film thickness of the charge transport layer is suitably about 5 to 100 μm. However, due to the recent demand for higher image quality, it has been attempted to make the charge transport layer thinner and achieve higher image quality of 1200 dpi or more. For this purpose, a thickness of about 5 to 30 μm is more preferable.

  Furthermore, when the charge transport layer is the outermost layer of the photoreceptor, the following general formula (1);

〔式中のＲ^１、Ｒ^２及びＲ^３は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｙはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基、Ｚ^１及びＺ^２は、それぞれ同一又は異なる水素原子、低級アルキル基又は

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

基（Ｒ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である）、ｍは１０，０００以下の正の整数、ｎは１以上の整数である〕
で表わされるポリオルガノシロキサンと、下記一般式（２）；

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2):

（式中のＲ^７は水素原子又はメチル基、Ｒ^８はアルキル基、アルコキシ置換アルキル基、シクロアルキル基又はアリール基である）
で表わされる（メタ）アクリル酸エステル又はこの（メタ）アクリル酸エステル７０重量％以上と共重合可能な単量体３０重量％以下との混合物とを、重量比５：９５ないし９５：５の割合で乳化グラフト共重合させて成るアクリル変性ポリオルガノシロキサンであり、しかもＮａイオン含有量が１００ｐｐｍ以下、Ｓイオン含有量が２００ｐｐｍ以下に精製したものを含有させる。

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization and having a Na ion content of 100 ppm or less and an S ion content of 200 ppm or less .

Here, the acrylic-modified polyorganosiloxane used in the present invention will be described.
This acrylic-modified polyorganosiloxane has (a) general formula (1);

（式中のＲ^１、Ｒ^２、Ｒ^３、Ｙ、Ｚ^１及びＺ^２は前記と同じ意味をもつ）
で表わされるポリオルガノシロキサンに、（ロ）一般式（２）；

(Wherein R ¹ , R ² , R ³ , Y, Z ¹ and Z ² have the same meaning as described above)
(B) General formula (2);

（式中のＲ^７、Ｒ^８は前記と同じ意味をもつ）
で表わされる（メタ）アクリル酸エステル及び所望に応じて用いられる共重合可能な単量体を、乳化重合法によりグラフト重合させることにより製造される。

(Wherein R ⁷ and R ⁸ have the same meaning as above)
(Meth) acrylic acid ester represented by the formula (1) and a copolymerizable monomer used as desired are produced by graft polymerization using an emulsion polymerization method.

In the polyorganosiloxane represented by the general formula (1), R ¹ , R ² and R ³ are alkyl groups such as methyl group, ethyl group, propyl group and butyl group, phenyl group, tolyl group and xylyl group, respectively. , Halogenated groups having 1 to 20 carbon atoms in which at least one of the hydrocarbon groups having 1 to 20 carbon atoms such as an aryl group such as a naphthyl group or the hydrogen atoms bonded to the carbon atoms of these hydrocarbon groups is substituted with a halogen atom It is a hydrocarbon group, Comprising: R < ¹ >, R < ² > and R < ³ > may be the same respectively, and may differ from one another.
Y is an organic group having a radical reactive group such as a vinyl group, an allyl group, a γ-acryloxypropyl group, a γ-methacryloxypropyl group, a γ-mercaptopropyl group, an SH group, or both. Z ¹ and Z ² are a hydrogen atom, a lower alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, or

で示されるトリオルガノシリル基であり、このトリオルガノシリル基におけるＲ^４及びＲ^５は、それぞれ同一又は異なる炭素数１〜２０の炭化水素基又はハロゲン化炭化水素基、Ｒ^６は炭素数１〜２０の炭化水素基もしくはハロゲン化炭化水素基、あるいはラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基である。該トリオルガノシリル基における炭素数１〜２０の炭化水素基、ハロゲン化炭化水素基及びラジカル反応性基又はＳＨ基もしくはその両方をもつ有機基としては、前記に例示したものを挙げることができる。該Ｚ１とＺ２は、それぞれ同一であってもよいし、たがいに異なるものであってもよい。
さらに、ｍは１０，０００以下の正の整数、好ましくは５００〜８，０００の範囲の整数であり、ｎは１以上の整数、好ましくは１〜５００の範囲の整数である。

Wherein R ⁴ and R ⁵ in the triorganosilyl group are the same or different, each having 1 to 20 carbon atoms or a halogenated hydrocarbon group, and R ⁶ is having 1 to 1 carbon atoms. An organic group having 20 hydrocarbon groups or halogenated hydrocarbon groups, or radical reactive groups and / or SH groups. Examples of the organic group having a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group, a radical reactive group and / or an SH group in the triorganosilyl group include those exemplified above. Z1 and Z2 may be the same or different from each other.
Further, m is a positive integer of 10,000 or less, preferably an integer in the range of 500 to 8,000, and n is an integer of 1 or more, preferably an integer in the range of 1 to 500.

The polyorganosiloxane represented by the general formula ( 1 ) is a cyclic polyorganosiloxane, a liquid polydimethylsiloxane in which both molecular chain ends are blocked with hydroxyl groups, a liquid polydimethylsiloxane in which both molecular chain ends are blocked with alkoxy groups, Further desired are polydimethylsiloxane having both ends of the molecular chain blocked with trimethylsilyl groups, silanes for introducing radical reactive groups and / or SH groups, or hydrolysis products of silanes. Accordingly, the trifunctional trialkoxysilane and the hydrolysis product thereof in such an amount that does not detract from the object of the present invention can be used for the reaction.

  Next, different examples of the method for producing the polyorganosiloxane represented by the general formula (1) will be described. First, the first method uses a cyclic low molecule such as the aforementioned octamethylcyclotetrasiloxane as a raw material. A method of obtaining a high molecular weight polyorganosiloxane by polymerizing in the presence of a strong alkali or strong acid catalyst using a dialkoxysilane compound having a radical reactive group or SH group or both, or a hydrolyzate thereof. is there. The high molecular weight polyorganosiloxane thus obtained is emulsified and dispersed in an aqueous medium in the presence of a suitable emulsifier in order to be used for the emulsion graft copolymerization in the next step.

  Next, the second method uses, as raw materials, for example, the low molecular polyorganosiloxane, a dialkoxysilane having a radical reactive group and / or an SH group, or a hydrolyzate thereof, and a sulfonic acid-based interface. In this method, emulsion polymerization is carried out in an aqueous medium in the presence of an activator or a sulfate ester surfactant. In this emulsion polymerization, the same raw materials are used, and after emulsifying and dispersing in an aqueous medium with a cationic surfactant such as alkyltrimethylammonium chloride or alkylbenzylammonium chloride, an appropriate amount of potassium hydroxide or sodium hydroxide is obtained. It can also be polymerized by adding a strong alkaline compound such as.

  When the polyorganosiloxane represented by the general formula (1) thus obtained has a low molecular weight, the molded article obtained from the composition is imparted with durable slidability and wear resistance. Since the effect becomes inferior, it is preferable that the molecular weight is as large as possible. For this reason, in the first method, it is necessary to leave the polyorganosiloxane of high molecular weight in the polymerization and to emulsify and disperse it, and in the second method, the aging treatment performed after the emulsion polymerization. In this case, since the molecular weight of the polyorganosiloxane increases if the temperature is lowered, the aging temperature is advantageously 30 ° C. or less, preferably 15 ° C. or less.

  In the present invention, the (meth) acrylic acid ester represented by the general formula (2) used as a monomer of the component (b) to be graft polymerized to the polyorganosiloxane represented by the general formula (1) For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2 -Alkoxyalkyl (meth) acrylates such as ethylhexyl (meth) acrylate, lauryl (meth) acrylate, alkyl (meth) acrylates such as stearyl (meth) acrylate, methoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, etc. Rate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate and benzyl (meth) acrylate. These (meth) acrylic acid esters may be used alone or in combination of two or more.

Moreover, a polyfunctional monomer and an ethylenically unsaturated monomer are mentioned as a copolymerizable monomer used with these (meth) acrylic acid esters as desired. Examples of the polyfunctional monomer include (meth) acrylamide, diacetone (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide, and N-methoxymethyl (meth) acrylamide. Ethylenically unsaturated amides and alkylols or alkoxyalkylated products of ethylenically unsaturated amides, oxirane group-containing unsaturated monomers such as glycidyl (meth) acrylate, glycidyl allyl ether, 2-hydroxyethyl (meth) acrylate, 2- Hydroxyl group-containing unsaturated monomers such as hydroxypropyl (meth) acrylate, carboxyl group-containing ethylenically unsaturated monomers such as (meth) acrylic acid, maleic anhydride, crotonic acid and itaconic acid, N-dimethylaminoethyl (Meta) Acry Amino group-containing unsaturated monomers such as N-diethylaminoethyl (meth) acrylate, polyalkylene oxide group-containing unsaturated monomers such as ethylene oxide and propylene oxide adducts of (meth) acrylic acid, ethylene glycol Examples include (meth) acrylates, diethylene glycol di (meth) acrylates, full esters of polyhydric alcohols such as trimethylolpropane tri (meth) acrylate and (meth) acrylic acid, and allyl (meth) acrylates and divinylbenzene. . These may be used alone or in combination of two or more.
These polyfunctional monomers have an effect of imparting elasticity, durability, heat resistance, and the like to the molded body by participating in crosslinking between polymers in the acrylic-modified polyorganosiloxane.

  On the other hand, examples of the ethylenically unsaturated monomer include styrene, α-methylstyrene, vinyl toluene, acrylonitrile, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl propionate, and vinyl versatate. These monomers may be used singly or in combination of two or more, or in combination of one or more of these monomers and one or more of the above functional monomers. May be.

The amount of the copolymerizable monomer used as desired is 30 based on the total weight of the (meth) acrylic acid ester represented by the general formula (2) and the copolymerizable monomer. It is necessary to select within the range of weight% or less. When this amount exceeds 30% by weight, the miscibility between the resulting acrylic-modified polyorganosiloxane and the binder resin is lowered.
Further, the monomer for graft copolymerization of the component (b), that is, the (meth) acrylic acid ester represented by the general formula (2), or a mixture thereof with a monomer copolymerizable therewith is a molded product. In order to impart superior slidability and wear resistance, it is desirable that the polymerized product has a glass transition temperature of 20 ° C., preferably 30 ° C. or higher.

The acrylic-modified polyorganosiloxane in the present invention is an emulsion polymerization method using the polyorganosiloxane of component (a) and the monomer of component (b) in a weight ratio of 5:95 to 95: 5. Is obtained by graft copolymerization. When the proportion of the polyorganosiloxane used as the component (a) is less than the above range, the resulting acrylic-modified polyorganosiloxane cannot sufficiently exhibit the effects of the polyorganosiloxane itself, and the disadvantages of the acrylic polymer If it exceeds the above range, the acrylic-modified polyorganosiloxane will be less miscible with the polyvinyl chloride resin and will easily bleed on the surface of the molded article, and it will have good slidability and resistance. There is a tendency that the wear and the like tend to decrease with time.
The emulsion graft copolymerization of the component (a) and the component (b) is carried out by a known emulsion polymerization method using an aqueous emulsion of polyorganosiloxane as the component (a) and a normal radical initiator. be able to.
The production of acrylic modified polyorganosiloxane is described in detail in Japanese Patent Publication No. 7-5808 (Nisshin Chemical Industry Co., Ltd.).

Further, in the acrylic-modified polyorganosiloxane used in the present invention, residual impurities such as emulsifiers and aggregating agents used in the polymerization may impair the electrical characteristics of image forming members that are problematic in electrical characteristics, particularly electrophotographic photoreceptors. Therefore, Ru used in manufactured by Seiko. Examples of the purification method include a method of stirring and washing with an acid, an aqueous alkali solution, water and alcohol, and a solid-liquid extraction method such as Soxhlet extraction.

  The proportion of the acrylic-modified polyorganosiloxane in the photosensitive layer is 70% by weight or less, more preferably 5% by weight or more and 50% by weight or less. If it is used in excess of 70% by weight, it causes side effects such as a decrease in surface smoothness of the photoreceptor and an increase in residual potential. On the other hand, if it is less than 5% by weight, the friction coefficient may be slightly insufficiently reduced, resulting in poor cleaning.

  As a method for adding the acrylic-modified polyorganosiloxane to the resin, means such as a method of stirring in a general-purpose solvent, a ball milling method, a vibration milling method, an ultrasonic method, and a high-speed liquid collision method can be used. Or the method of mechanically mixing using well-known apparatuses, such as a Banbury mixer, a roll mill, and a twin-screw extruder, and shape | molding in a pellet form can be mentioned. Extruded pellets can be molded over a wide temperature range, and a normal injection molding machine is used for molding. The graft copolymer and resin having a core / shell structure shaped into pellets can be further applied to the above solution dispersion method.

The following are typical examples of the acrylic-modified polyorganosiloxane used in the present invention.
For example, what was further refine | purified what is marketed by brand names, such as Charine R-170S, R-170, R-210 of Nissin Chemical Industry Co., Ltd. is mentioned.
Further, in addition to the acrylic-modified polyorganosiloxane, fine particles can be added to the surface portion of the charge transport layer for the purpose of improving the wear resistance. Fine particles used for improving wear resistance include fluorine resin fine particles such as polytetrafluoroethylene, silicon resin fine particles, guanamine formaldehyde resin fine particles, a-carbon powder, copper, tin, aluminum, indium, etc. Metal oxide such as silica, tin oxide, zinc oxide, titanium oxide, alumina, indium oxide, antimony oxide, bismuth oxide, calcium oxide, tin oxide doped with antimony, tin oxide doped indium oxide And inorganic fine particles such as metal fluorides such as tin fluoride, calcium fluoride and aluminum fluoride, potassium titanate and boron nitride. As a result, the effect of reducing the surface friction coefficient, the improvement of wear resistance, the improvement of toner transfer efficiency, the improvement of the cleaning performance of residual toner, etc. are further effectively demonstrated. It is very effective for extending the service life.

As the organic solvent used for the charge transport layer forming coating solution, the same solvent as the above-described charge generating layer forming coating solution is used.
The charge transport layer forming coating solution is produced by dissolving the charge transport material and the binder resin in the organic solvent and dispersing the acrylic-modified polyorganosiloxane used in the present invention. Furthermore, even when the fine particles are dispersed for the above purpose, the same dispersion method as that for the charge generation layer forming coating solution can be used.

When the acrylic-modified polyorganosiloxane is contained in the charge transport layer, it is preferable to increase the content in the vicinity of the surface of the charge transport layer in order to obtain a friction coefficient reducing effect more efficiently.
That is, it may be contained above the film thickness that can no longer function as an electrophotographic photosensitive member due to wear of the charge transport layer due to repeated use, and the acrylic modified polyorganosiloxane contained therein is wasted. In addition, the electrophotographic characteristics of the photoreceptor may be adversely affected. As a method for producing an electrophotographic photosensitive member containing a large amount of acrylic-modified polyorganosiloxane near the surface of the charge transport layer, for example, after applying a coating liquid for forming a charge transport layer that does not contain acrylic-modified polyorganosiloxane, A method such as applying a coating solution for forming a charge transport layer containing a modified polyorganosiloxane can be considered.

  For example, specifically, a first charge transport layer is first formed on a charge generation layer using a charge transport layer forming coating solution that does not contain an acryl-modified polyorganosiloxane. A charge transport layer containing a large amount of acrylic-modified polyorganosiloxane on the surface is formed by forming a second charge transport layer using a coating liquid for forming a charge transport layer having an organosiloxane content of 40% by weight and then drying. A layer can be formed.

Next, the case where the photosensitive layer has a single layer structure will be described.
When a single-layer photosensitive layer is provided by a casting method, in many cases, such a single-layer photosensitive layer is obtained by dissolving or dispersing a charge generating substance, a low molecular weight molecule, and a polymer charge transporting substance in an appropriate solvent, and applying and drying the solution. Can be formed. As the charge generating substance and the charge transporting substance, the materials described above can be used.
In addition, a plasticizer can be added to the single-layer photosensitive layer as necessary. Furthermore, as the binder resin that can be used as necessary, the binder resins mentioned above for the charge transport layer can be used as they are. In addition, the binder resin mentioned in the charge generation layer may be mixed and used.

  Further, when the single-layer photosensitive layer is the outermost layer of the photoreceptor, the single-layer photosensitive layer contains an acrylic-modified polyorganosiloxane. As a result, the same effect as that of the charge transport layer described above can be obtained.

Further, as in the case of the above-described charge transport layer, it is preferable to increase the content of the acrylic-modified polyorganosiloxane near the surface, and the same production method can be used for this method.
The thickness of the photosensitive layer of the single-layer photoreceptor is suitably about 5 to 100 μm.

  In the photoreceptor of the present invention, a protective layer may be provided on the photosensitive layer. Materials used for the protective layer include ABS resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, aryl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallylsulfone, polybutylene, Polybutylene terephthalate, polycarbonate, polyethersulfone, polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylbenten, polypropylene, polyphenylene oxide, polysulfone, polystyrene, polyarylate, AS resin, butadiene-styrene copolymer, polyurethane, polychlorinated Examples thereof include resins such as vinyl, polyvinylidene chloride, and epoxy resin.

  Moreover, when using a protective layer, since a protective layer becomes the outermost layer, acrylic modified polyorganosiloxane is contained in the protective layer. In the present invention, the inclusion of the acryl-modified polyorganosiloxane maintains a low coefficient of friction even during repeated use over a long period of time and improves wear resistance. Furthermore, since the protective layer is provided on the photosensitive layer with a relatively small film thickness, the influence on the electrical characteristics of the photoreceptor is relatively small, and it is contained compared with the case where the charge transport layer contains an acrylic-modified polyorganosiloxane. The amount can be increased, or the charge transport layer can be functionally separated using a formulation specialized in reducing the friction coefficient and wear resistance. When the content of the outermost layer is large, there is an advantage that the friction coefficient becomes lower and the low friction coefficient is maintained even by repeated use.

  Further, the protective layer may contain fine particles other than acrylic-modified polyorganosiloxane in order to impart further wear resistance. As the fine particles, those described above can be used, and metal oxide fine particles such as silica, alumina and titanium oxide are particularly preferable. These fine particles are used alone or in combination of two or more.

In addition, the inclusion of a charge transport material in the protective layer is very useful for suppressing the electrical characteristics of the photoreceptor, in particular, the deterioration of photosensitivity during repeated use and the increase in residual potential. This is considered to be because the charge can be smoothly transferred to the surface of the photoreceptor by providing the protective layer also with charge transportability. As such a charge transporting substance, the charge transporting substance used in the charge transporting layer mentioned above can be used.
Furthermore, various additives may be added to the protective layer of the electrophotographic photoreceptor according to the present invention for the purpose of improving adhesiveness, smoothness, and chemical stability.

The protective layer according to the present invention is formed on the photosensitive layer using a conventional coating method such as dip coating, spray coating, blade coating, knife coating or the like. In particular, dip coating and spray coating are advantageous in terms of mass productivity and coating film quality.
The thickness of the protective layer thus obtained is suitably in the range of 0.1 to 15 μm, more preferably 1 to 10 μm.

Next, the image forming apparatus of the present invention will be described with reference to the drawings.
FIG. 5 is a schematic view for explaining the image forming apparatus of the present invention, and FIG. 6 is an enlarged view of the cleaning unit. Note that the following modifications also belong to the category of the present invention.
As shown in FIG. 5, the image forming apparatus using the electrophotographic photosensitive member according to the present invention includes a drum-shaped photosensitive member (1), a charging charger (3), and a pre-transfer charger (7). And a transfer charger (10), a separation charger (11), a cleaning unit (17) as shown in FIG.
The shape of the photoreceptor (1) is not limited to a drum shape, and may be, for example, a sheet shape or an endless belt shape. As various chargers, known means such as a corotron, a scorotron, a solid state charger (solid state charger), and a charging roller can be used.
As the transfer means, the above charger can be generally used, but a combination of a transfer charger and a separation charger as shown in the figure is effective.

Further, light sources such as an image exposure unit (5) and a charge removal lamp (2) include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL). ) And other luminescent materials can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.
Such a light source or the like can irradiate the photoreceptor with light by providing a transfer step, a static elimination step, a cleaning step, or a pre-exposure step in combination with light irradiation in addition to the steps shown in FIG. .

  The toner developed on the photoreceptor (1) by the developing unit (6) is transferred to the transfer paper (9), but not all is transferred, and the toner is not transferred onto the photoreceptor (1). Remains. Such toner is removed from the photoreceptor by the cleaning brush (14) and the blade (15). Cleaning may be performed by a cleaning brush or a blade alone, and known cleaning brushes such as a fur brush and a mag fur brush are used as the cleaning brush.

  When the electrophotographic photosensitive member is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member. A positive image can be obtained by developing this with negative (positive) toner (electrodetection fine particles), and a negative image can be obtained by developing with positive (negative) toner. As this developing means, a known method is applied, and a known method is also used as the charge eliminating means.

The image forming apparatus of the present invention includes a mechanism for applying a lubricity imparting agent to the surface of the photoreceptor.
In the example of FIG. 6, the solid material in which the lubricity imparting agent (14) is made into a rod shape is pressed against the cleaning brush (16), and when the cleaning brush rotates, the lubricity imparting agent is scraped and adhered to the brush. The lubricity imparting agent thus applied is applied to the surface of the photoreceptor. The lubricity-imparting agent need not be solid and is not particularly limited as long as it can be applied to the surface of the photoreceptor even in a liquid, powder or semi-kneaded form and satisfies the electrophotographic characteristics.

  Examples of lubricity-imparting agents include metal soaps such as zinc stearate, barium stearate, aluminum stearate, calcium stearate, waxes such as carnauba, lanolin, and wax, and lubricating oils such as silicone oil. . In particular, zinc stearate, aluminum stearate, and calcium stearate, which are relatively easy to process into a rod shape and have a high lubricating effect, are particularly preferably used.

  As shown in FIG. 6, the provision of the lubricity-imparting agent application mechanism in the cleaning unit has advantages such as easier layout design around the drum and simplification of the apparatus, but the cleaned toner has a merit. In some cases, a large amount of the lubricity imparting agent is mixed, so that it is difficult to recycle the toner or the brush cleaning efficiency is lowered. Although not shown, the above problem can be solved by providing a coating unit having a lubricity imparting agent coating mechanism independently of the cleaning unit. In that case, the coating unit is preferably provided downstream of the cleaning unit. Furthermore, by providing coating units at a plurality of locations and operating them simultaneously or sequentially, there are effects such as increasing the coating efficiency of the lubricity imparting agent and controlling the consumption amount, which is useful.

FIG. 7 shows an example of another process using the image forming apparatus of the present invention.
In FIG. 7, a photoconductor (22) is a seamless belt-shaped electrophotographic photoconductor, which is driven by a driving roller (23), charged by a charging charger (20), image exposure by a light source (21), and development (FIG. 7). Not shown), transfer using the charger (25), cleaning with the cleaning brush (26), and static elimination with the light source (27) are repeated.

  Here, although not shown, the cleaning brush (26) is provided with a lubrication agent coating mechanism similar to that shown in FIG. 6, and the lubricity imparting agent is applied to the photoreceptor simultaneously with cleaning. . As described above, the lubricity imparting agent coating mechanism may be a single coating unit or a plurality of lubrication agent coating mechanisms may be installed.

Further, an embodiment of an electrophotographic printer (hereinafter simply referred to as a printer) will be described as a full-color image forming apparatus to which the present invention is applied.
FIG. 8 is a schematic configuration diagram of the printer according to the present embodiment.
In the drawing, the photosensitive member (56), which is a latent image carrier, is rotated counterclockwise in the drawing, and the surface thereof is uniformly charged by a charging charger (53) using a corotron, a scorotron, etc. The electrostatic latent image is carried by scanning with the laser beam L emitted from the laser optical device that does not. Since this scanning is performed based on single-color image information obtained by separating a full-color image into yellow, magenta, cyan, and black color information, a single-color image of yellow, magenta, cyan, or black is used on the photosensitive drum (56). An electrostatic latent image is formed. A revolver developing unit (50) is disposed on the left side of the photosensitive drum (56) in the drawing. This has a yellow developing unit, a magenta developing unit, a cyan developing unit, and a black developing unit in a rotating drum-shaped casing, and each developing unit is opposed to the photosensitive drum (56) by the rotation. To move sequentially. The yellow developer, magenta developer, cyan developer, and black developer are for developing an electrostatic latent image by attaching yellow toner, magenta toner, cyan toner, and black toner, respectively. On the photosensitive drum (56), electrostatic latent images for yellow, magenta, cyan, and black are sequentially formed, and these images are sequentially developed by the developing units of the revolver developing unit (50), so that a yellow toner image, magenta A toner image, a cyan toner image, and a black toner image are obtained.

  An intermediate transfer unit is disposed on the downstream side of the photosensitive drum (56) from the development position. This includes an intermediate transfer belt (58) stretched by a stretch roller (59a), an intermediate transfer bias roller (57) as a transfer means, a secondary transfer backup roller (59b), and a belt drive roller (59c). The belt drive roller (59c) is endlessly moved clockwise in the figure by the rotational drive. The yellow toner image, magenta toner image, cyan toner image, and black toner image developed on the photosensitive drum (56) enter the intermediate transfer nip where the photosensitive drum (56) and the intermediate transfer belt (58) are in contact with each other. To do. Then, while being influenced by the bias from the intermediate transfer bias roller (57), the toner image is superimposed on the intermediate transfer belt (58) and intermediately transferred to form a four-color superimposed toner image.

  The surface of the photosensitive drum (56) that has passed through the intermediate transfer nip with the rotation is cleaned of the transfer residual toner by the drum cleaning unit (55). The cleaning unit (55) is for cleaning the transfer residual toner by a cleaning roller to which a cleaning bias is applied. However, the cleaning unit (55) may be a cleaning brush such as a fur brush or a mag fur brush, or a cleaning blade. Good.

Although not shown, the drum cleaning unit (55) is provided with a lubricity imparting agent application mechanism as shown in FIG. 6 and applies the lubricity imparting agent to the surface of the photoreceptor simultaneously with cleaning. As described above, the lubricity imparting agent coating mechanism may be a single coating unit or a plurality of lubrication agent coating mechanisms may be installed.
The surface of the photosensitive drum (56) from which the transfer residual toner has been cleaned is discharged by a discharging lamp (54). As the charge removal lamp (54), a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), an electroluminescence (EL), or the like is used. A semiconductor laser is used as the light source of the laser optical device. About these emitted lights, you may make it use only a desired wavelength range by various filters, such as a sharp cut filter, a band pass filter, a near-infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter.

  On the other hand, the registration roller pair (61) that sandwiches the transfer paper (60) sent from a paper feed cassette (not shown) between the two rollers has four colors on the intermediate transfer belt (58). The toner is fed toward the secondary transfer nip at a timing at which the toner image can be superimposed. The four-color superimposed toner image on the intermediate transfer belt (58) is subjected to the influence of the secondary transfer bias from the paper transfer bias roller (63) in the secondary transfer nip and collectively onto the transfer paper P. Transcribed. By this secondary transfer, a full color image is formed on the transfer paper (60).

  The transfer paper (60) on which the full-color image is formed is sent to the paper transport belt (64) by the transfer belt (62). The conveying belt (64) feeds the transfer paper (60) received from the transfer unit into the fixing device (65). The fixing device (65) conveys the transferred transfer paper (60) while being sandwiched between fixing nips formed by the contact between the heating roller and the backup roller. The full-color image on the transfer paper (60) is fixed on the transfer paper (60) under the influence of the heating from the heating roller and the pressure in the fixing nip.

Although not shown, a bias for adsorbing the transfer paper (60) is applied to the transfer belt (62) and the conveyance belt (64). In addition, a paper neutralization charger that neutralizes the transfer paper (60) and three belt neutralization chargers that neutralize each belt (intermediate transfer belt (58), transfer belt (62), and conveyance belt (64)) are provided. Yes. The intermediate transfer unit also includes a belt cleaning unit having the same configuration as that of the drum cleaning unit (55), thereby cleaning the transfer residual toner on the intermediate transfer belt (58).
Here, the cleaning unit of the intermediate transfer unit is provided with a lubricity imparting agent coating mechanism so that the surface of the intermediate transfer belt can have a low friction coefficient, or the transfer residual toner in the secondary transfer of the toner to the transfer paper (60). It is very effective for reduction.

FIG. 9 is a modification of the image forming apparatus according to the present embodiment. This apparatus is a tandem image forming apparatus having an intermediate transfer belt (87), and does not share the photosensitive drum (80) for each color, but the photosensitive drums (80Y), (80M) for the respective colors. (80C) and (80Bk). A drum cleaning unit (85), a charge removal lamp (83), and a charging roller (84) for uniformly charging the drum are also provided for each color. The drum cleaning unit (85) is provided with a lubricity imparting agent application mechanism as shown in FIG. As described above, the lubricity imparting agent coating mechanism may be a single coating unit or a plurality of lubrication agent coating mechanisms may be installed. In the printer shown in FIG. 8, the charging charger (53) is provided as the drum uniform charging means, but in this apparatus, the charging roller (84) is provided.
In the tandem method, latent image formation and development of each color can be performed in parallel, so that the image formation speed can be much faster than the revolver method.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to the aspect of the following Example. In addition, all "parts" which are units used in the following examples and comparative examples are based on weight.
<Example 1>
15 parts by weight of alkyd resin (Beckolite M6401-50 (manufactured by Dainippon Ink and Chemicals)), 10 parts by weight of melamine resin (Super Becamine G-821-60 (manufactured by Dainippon Ink and Chemicals)) and 150 parts by weight of methyl ethyl ketone 90 parts by weight of titanium oxide powder (Typaque CR-EL (manufactured by Ishihara Sangyo Co., Ltd.)) was added thereto and dispersed for 12 hours by a ball mill to prepare an undercoat layer coating solution.
This was coated on a cylindrical aluminum substrate having a diameter of 90 mm and a length of 392 mm by a dip coating method and dried at 130 ° C. for 20 minutes to form an undercoat layer having a thickness of 3.5 μm.
Next, 4 parts by weight of polyvinyl butyral resin (XYHL (manufactured by UCC)) is dissolved in 150 parts by weight of cyclohexanone, which is represented by the following structural formula (I).

ビスアゾ顔料に１０重量部を加え、ボールミルで４８時間分散後、さらにシクロヘキサノン２１０重量部を加えて３時間分散を行なった。これを容器に取り出し固形分が１．５重量％となるようにシクロヘキサノンで稀釈した。こうして得られた電荷発生層用塗工液を前記中間層上に塗工し１３０℃２０分間乾燥し厚み０．２μｍの電荷発生層を形成した。
次に、テトラヒドロフラン１００重量部に、ビスフェノールＺ型ポリカーボネート樹脂１０重量部、シリコーンオイル（ＫＦ−５０（信越化学工業社製））０．００２重量部を溶解し、これに下記構造式（II）の電荷輸送物質１０重量部を加えて電荷輸送層用塗工液を作製した。こうして得られた電荷輸送層用塗工液を電荷発生層上に浸漬塗工法によって塗工し、その後１１０℃２０分間乾燥し、厚み２０μｍの電荷輸送層を形成した。

10 parts by weight was added to the bisazo pigment and dispersed for 48 hours by a ball mill, and further 210 parts by weight of cyclohexanone was added and dispersed for 3 hours. This was taken out into a container and diluted with cyclohexanone so that the solid content was 1.5% by weight. The charge generation layer coating solution thus obtained was applied onto the intermediate layer and dried at 130 ° C. for 20 minutes to form a charge generation layer having a thickness of 0.2 μm.
Next, 10 parts by weight of bisphenol Z-type polycarbonate resin and 0.002 parts by weight of silicone oil (KF-50 (manufactured by Shin-Etsu Chemical Co., Ltd.)) are dissolved in 100 parts by weight of tetrahydrofuran, and the following structural formula (II) A charge transport layer coating solution was prepared by adding 10 parts by weight of the charge transport material. The charge transport layer coating solution thus obtained was applied onto the charge generation layer by a dip coating method and then dried at 110 ° C. for 20 minutes to form a charge transport layer having a thickness of 20 μm.

Next, an Example is shown about the refinement | purification of the acrylic modified polyorganosiloxane used for the present Example.
1) Purification example 1 of acrylic modified polyorganosiloxane
30 g of acrylic-modified polyorganosiloxane (Charine R170S (volume average particle size (D50) = 30 μm) manufactured by Nissin Chemical Industry Co., Ltd.) is taken up in 300 g of methanol, and after stirring for 60 minutes twice, ion-exchanged water is used. Replaced. The obtained acrylic-modified polyorganosiloxane was lyophilized to obtain 27.76 g. Elemental analysis of the purified acrylic-modified polyorganosiloxane was performed by fluorescent X-ray analysis. The results are shown in Table 1.

2) Purification example 2 of acrylic modified polyorganosiloxane
30 g of acrylic-modified polyorganosiloxane (Charine R170S (volume average particle size (D50) = 30 μm) manufactured by Nissin Chemical Industry Co., Ltd.) was taken up in 300 g of methanol, and after stirring for 60 minutes three times, Replaced. The obtained acrylic-modified polyorganosiloxane was lyophilized to obtain 26.67 g. Elemental analysis of the purified acrylic-modified polyorganosiloxane was performed by fluorescent X-ray analysis. The results are shown in Table 1.

Acrylic modified Porioruganoshi Rokisa down 1 part by weight obtained in Purification Example 1, the 9 parts by weight of bisphenol Z-type polycarbonate resin, tetrahydrofuran 300 parts by weight, in addition to the cyclohexanone 90 parts by weight to prepare a protective layer coating liquid. Using the spray gun (Peacecon PC308, manufactured by Olympos Co., Ltd.), the coating liquid for forming the protective layer thus obtained was spray-coated at an air pressure of 2 kgf / cm 2 and applied three times. The film was dried at 20 ° C. for 20 minutes to form a protective layer having a thickness of 5 μm, and the electrophotographic photosensitive member of Example 1 was produced.

Next, production examples of the polymerized toner used in this example are shown.
1) Preparation of monomer composition Styrene monomer 70 parts n-butyl methacrylate 30 parts polystyrene 5 parts 3,5-di-tert-butylsalicylic acid zinc salt 2 parts carbon black 6 parts The above polymerizable monomer mixture is ball milled Was used for dispersion for 24 hours to prepare a monomer composition.

2) Granulation, polymerization 2% polyvinyl alcohol aqueous solution in a flask equipped with a stirrer, a thermometer, an inert gas introduction tube and a porous glass tube with a pore diameter of 110,000 kg, a pore volume of 0.42 cc / g, 10φ × 50 mm 400 ml was taken and stirred at room temperature while feeding nitrogen gas to replace oxygen in the reaction vessel with nitrogen.
Next, 1.56 g of azobisisobutylnitrile was added to 113 g of the monomer composition of 1), dissolved by stirring, passed through a porous glass tube using a pump, added into an aqueous polyvinyl alcohol solution, and after addition, polyvinyl alcohol The monomer composition was circulated at a rate of about 120 ml / min for 2 hours using the pump and the porous glass tube, and then the internal temperature was set to 70 ° C. and polymerization was performed for 8 hours.
After cooling to room temperature and allowing to stand overnight, the supernatant was removed, water was added, the mixture was stirred for 1 hour, filtered and dried to obtain a toner. When the particle diameter of this toner was measured with a Coulter counter, the average particle diameter was 8.5 μm, and the particles in the range of 5 to 0 μm were 95% of the total, showing a very narrow particle size distribution.
In addition, as a method for measuring the shape, an optical detection band method is suitable in which a suspension containing particles is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. The average circularity, which is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle, was 0.98.
The polymerized toner thus obtained was mixed with a carrier at a toner concentration of 4% to obtain a two-component developer.
The two-component developer thus obtained and another electrophotographic photosensitive member produced in the same manner as in the above-described production method were converted into a full-color composite machine Imagio Color 5100 (manufactured by Ricoh) with an image exposure light source of 655 nm. Change the conditions such as contact with the cleaning brush, contact pressure with the cleaning blade, gap with the developing part, etc. Mounted on the photoconductor wear) and adjusting the voltage of the charger so that the non-exposed portion potential (VD) becomes −700 V, and then writing by 600 dpi, A4 size Execute a running test that outputs a test image with an image area ratio of 6%, and measure the amount of wear from the difference in film thickness of the photosensitive layer before and after the running test. It was. For film thickness measurement, an eddy current film thickness meter Fischer scope MMS (manufactured by Fischer) was used. Furthermore, an initial image before the running test and a durable image after the running test were output, and the image quality was also evaluated.

Here, the background dirt that seems to be caused by poor cleaning was evaluated with the following ranks.
Rank 5: Almost no dirt on the surface, good level Rank 4 ... Level where there is a little background dirt, but there is almost no problem Rank 3 ... Level where there is a little background dirt, but there is no problem in practical use Rank 2 ... Levels where the background dirt is conspicuous and unfavorable in actual use Rank 1 ... Level unacceptable in actual use

<Example 2>
An electrophotographic photosensitive member of Example 2 was prepared in the same manner as in Example 1 except that the amounts of the acrylic-modified polyorganosilane and bisphenol Z-type polycarbonate resin in Purification Example 1 were 3 parts by weight and 7 parts by weight, respectively. Was evaluated.

<Example 3>
An electrophotographic photosensitive member of Example 3 was prepared in the same manner as in Example 1 except that the amounts of the acrylic-modified polyorganosilane and bisphenol Z-type polycarbonate resin in Purification Example 1 were changed to 6 parts by weight and 4 parts by weight, respectively. Was evaluated.

<Example 4>
The electrophotographic photoreceptor of Example 4 was prepared in the same manner as in Example 1 except that the amounts of the acrylic-modified polyorganosilane and the bisphenol Z-type polycarbonate resin in Purification Example 1 were 0.3 parts by weight and 9.7 parts by weight, respectively. A similar evaluation was made.

<Example 5>
Example 1 except that the amounts of the acrylic modified polyorganosilane and bisphenol Z-type polycarbonate resin in Purification Example 1 were 1 part by weight and 9 parts by weight, respectively, and 7 parts by weight of the charge transport material of the structural formula (II) was added. Similarly, an electrophotographic photosensitive member of Example 5 was produced and evaluated in the same manner.

<Example 6>
The amounts of the acrylic modified polyorganosilane and the bisphenol Z-type polycarbonate resin in Purification Example 1 were 3 parts by weight and 7 parts by weight, respectively, except that 7 parts by weight of the charge transport material of the structural formula (II) was added. Similarly, an electrophotographic photosensitive member of Example 6 was produced and evaluated in the same manner.

<Example 7>
An electrophotographic photosensitive member of Example 7 was produced in the same manner as in Example 6 except that aluminum stearate was used instead of zinc stearate as a lubricity imparting agent, and the same evaluation was performed.

<Example 8>
An electrophotographic photosensitive member of Example 8 was produced in the same manner as in Example 6 except that calcium stearate was used instead of zinc stearate as a lubricity imparting agent, and the same evaluation was performed.

<Example 9>
An electrophotographic photosensitive member of Example 9 was produced in the same manner as in Example 6 except that purified lanolin (trade name: Lanolin TR, manufactured by Nippon Seika Co., Ltd.) was used instead of zinc stearate as a lubricant imparting agent. The same evaluation was performed.

<Comparative Example 1>
An electrophotographic photosensitive member of Comparative Example 1 was produced in the same manner as in Example 6 except that the acrylic-modified polyorganosiloxane was not added, and the same evaluation was performed.

<Comparative example 2>
An electrophotographic photosensitive member of Comparative Example 2 was produced in the same manner as in Example 7 except that the acrylic-modified polyorganosiloxane was not added, and the same evaluation was performed.

<Comparative Example 3>
An electrophotographic photosensitive member of Comparative Example 3 was produced in the same manner as in Example 8 except that the acrylic-modified polyorganosiloxane was not added, and the same evaluation was performed.

<Comparative example 4>
An electrophotographic photosensitive member of Comparative Example 4 was produced in the same manner as in Example 9 except that the acrylic-modified polyorganosiloxane was not added, and the same evaluation was performed.

<Comparative Example 5>
An electrophotographic photosensitive member of Comparative Example 5 was produced in the same manner as in Example 5 except that the lubricity imparting agent coating mechanism of the image forming apparatus was removed, and the same evaluation was performed.

<Comparative Example 6>
An electrophotographic photoreceptor of Comparative Example 6 was produced in the same manner as in Example 6 except that the lubricity imparting agent coating mechanism of the image forming apparatus was removed, and the same evaluation was performed.
The evaluation results thus obtained are shown in Table 2.

<Examples 10-13, Comparative Examples 7-9>
The electrophotographic photosensitive members of Examples 6 to 9 and Comparative Examples 1, 5, and 6 were prepared using a cylindrical aluminum substrate having a diameter of 30 mm and a length of 340 mm, and a remodeling machine for an image forming apparatus IPSiO Color 8200 (manufactured by Ricoh Company). (Change the conditions such as the cleaning brush contact pressure, the cleaning blade contact pressure, and the gap between the development unit and the like. Mounted on the photosensitive member with a load applied), and the voltage of the charger is adjusted so that the non-exposure portion potential (VD) becomes −700 V, and then A4 is written by writing equivalent to 600 dpi. 50,000 running tests that output a test image with a size and image area ratio of 6% were performed, and the amount of wear was measured from the difference in film thickness of the photosensitive layer before and after the running test. . For film thickness measurement, an eddy current film thickness meter Fischer scope MMS (manufactured by Fischer) was used. Furthermore, an initial image before the running test and a durable image after the running test were output, and the image quality was also evaluated.
Here, scoring due to poor cleaning was ranked and evaluated in the same manner as described above.
Table 3 shows the evaluation results thus obtained.

<Examples 14 to 21, Comparative Examples 10 to 15>
The electrophotographic photosensitive members of Examples 1 to 4, 6 to 9, and Comparative Examples 1 to 6 were prepared using a cylindrical aluminum substrate having a diameter of 30 mm and a length of 340 mm, and the tandem intermediate transfer type image forming apparatus of FIG. It is installed and the cleaning brush in each photoconductor unit is installed so that a solid bar-like material formed by heating and melting zinc stearate is in contact with it, conditions such as the cleaning blade contact pressure, the gap with the developing unit, etc. The load is applied to the wear of the photoconductor and the voltage of the charger is adjusted so that the non-exposure portion potential (VD) becomes −700 V, and then the A4 size and the image area ratio are written by writing equivalent to 600 dpi. A running test for outputting a test image of 6% was performed 50,000 sheets, and the amount of wear was measured from the difference in film thickness of the photosensitive layer before and after the running test. For film thickness measurement, an eddy current film thickness meter Fischer scope MMS (manufactured by Fischer) was used. Furthermore, an initial image before the running test and a durable image after the running test were output, and the image quality was also evaluated.
Here, scoring due to poor cleaning was ranked and evaluated in the same manner as described above.
The evaluation results thus obtained are shown in Table 4.

FIG. 2 is a schematic cross-sectional view illustrating an example of a layer configuration of the electrophotographic photosensitive member of the present invention. FIG. 4 is a schematic cross-sectional view showing another example of the layer configuration of the electrophotographic photosensitive member of the present invention. FIG. 4 is a schematic cross-sectional view showing another example of the layer configuration of the electrophotographic photosensitive member of the present invention. FIG. 6 is a schematic cross-sectional view showing another example of the layer configuration of the electrophotographic photosensitive member of the present invention. 1 is a schematic view of an example of an image forming apparatus of the present invention. Schematic of an example of the lubricity imparting agent coating mechanism of the image forming apparatus of the present invention. 1 is a schematic configuration diagram of an example of a printer that is an example of an image forming apparatus of the present invention. 1 is a schematic configuration diagram of an example of a color printer that is an example of an image forming apparatus of the present invention. FIG. 3 is a schematic configuration diagram of a modification example of a color printer that is an example of the image forming apparatus of the present invention. 1 is a schematic configuration diagram of an example of a deformation apparatus of a color copying machine that is an example of an image forming apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Static elimination lamp 3 Charger charger 4 Eraser 5 Image exposure part 6 Development unit 7 Charger before transfer 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation charger 12 Separation nail 13 Charger 14 before cleaning 14 Fur brush 15 Cleaning brush 16 Lubricity Giving agent 17 Cleaning unit 20 Charge charger 21 Image exposure light source 22 Photoconductor 23 Driving roller 24 Tension roller 25 Transfer charger 26 Cleaning brush 27 Static elimination light source 28 Follower roller 50 Development unit 53 Charge charger 54 Static elimination lamp 55 Drum cleaning unit 56 Photoconductor 57 Bias roller 58 Intermediate transfer belt 59a Tension roller 59b Backup roller 59c Belt drive roller 60 Transfer paper 61 Registration roller 62 Transfer bell 63 paper transfer bias roller 64 the conveyor belt 65 fixing unit L exposure 80 photoconductor 81 exposure light source 82 developing unit 83 eliminating lamp 84 charging roller 85 a cleaning unit 86 bias roller 87 intermediate transfer belt 88 registration rollers 89 paper (image bearing member)
90 Paper transfer bias roller 91 Transfer belt 92 Conveying belt 93 Fixing unit 94 Fur brush

Claims (15)

In an image forming apparatus having at least an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit, and a transferring unit, the electrophotographic photosensitive member includes an electron having a layer containing at least a charge generating substance and a charge transporting substance on a conductive support. It is a photographic photoreceptor, and the following general formula (1)

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical An organic group having a reactive group and / or an SH group), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2)

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. An image forming apparatus comprising a mechanism for applying a lubricity imparting agent to a surface. 2. The image forming apparatus according to claim 1, wherein the content of the acrylic-modified polyorganosiloxane contained in the outermost layer is 5% by weight to 50% by weight. The image forming apparatus according to claim 1, wherein the outermost layer contains a binder resin and a charge transporting substance. The image forming apparatus according to claim 1, wherein the lubricity imparting agent is a metal soap. The image according to any one of claims 1 to 4, wherein a metal soap selected from zinc stearate, aluminum stearate, and calcium stearate is used alone or in combination of two or more as the lubricity-imparting agent. Forming equipment. 6. The image forming apparatus according to claim 1, wherein the image forming apparatus is a tandem type having a plurality of electrophotographic photosensitive members, a charging unit, a developing unit, and a transfer unit. An image having intermediate transfer means for primary transfer of the toner image developed on the electrophotographic photosensitive member onto the intermediate transfer member by the image forming apparatus and then secondary transfer of the toner image on the intermediate transfer member onto the recording material. 2. The forming apparatus according to claim 1, wherein a color image is formed by sequentially superimposing a plurality of color toner images on an intermediate transfer member, and the color image is secondarily transferred collectively onto a recording material. The image forming apparatus according to claim 6. In an image forming method using an image forming apparatus having at least an electrophotographic photosensitive member and having at least a charging step, an exposure step, a developing step, and a transfer step, the electrophotographic photosensitive member has at least a charge generating substance and a charge on a conductive support. An electrophotographic photosensitive member having a layer containing a transport material, the outermost surface layer of which is represented by the following general formula (1)

[In the formula, R ¹ , R ² and R ³ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, Y is an organic group having a radical reactive group, an SH group or both. , Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups or

Groups (R ⁴ and R ⁵ are the same or different, respectively, a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, or a radical A reactive group or an organic group having an SH group or both), m is a positive integer of 10,000 or less, and n is an integer of 1 or more.
And a polyorganosiloxane represented by the following general formula (2)

(Wherein R ⁷ is a hydrogen atom or a methyl group, R ⁸ is an alkyl group, an alkoxy-substituted alkyl group, a cycloalkyl group or an aryl group)
(Meth) acrylic acid ester or a mixture of 70% by weight or more of this (meth) acrylic acid ester and 30% by weight or less of a copolymerizable monomer in a weight ratio of 5:95 to 95: 5 And an acrylic-modified polyorganosiloxane obtained by emulsion graft copolymerization , wherein the Na ion content is 100 ppm or less and the S ion content is 200 ppm or less , and the image forming apparatus is an electrophotographic photoreceptor. An image forming method comprising a mechanism for applying a lubricity imparting agent to a surface. The image forming method according to claim 8, wherein the content of the acrylic-modified polyorganosiloxane contained in the outermost layer is 5% by weight to 50% by weight. The image forming method according to claim 8 or 9, wherein the outermost layer contains a binder resin and a charge transporting substance. The image forming method according to claim 8, wherein the lubricity-imparting agent is a metal soap. The image according to any one of claims 8 to 11, wherein a metal soap selected from zinc stearate, aluminum stearate, and calcium stearate is used alone or in combination of two or more as the lubricity imparting agent. Forming method. 13. The image forming method according to claim 8, wherein the image forming method is a tandem type having a plurality of electrophotographic photosensitive members, a charging step, a developing step, and a transfer step. An image having an intermediate transfer step in which the image forming method primarily transfers a toner image developed on an electrophotographic photosensitive member onto an intermediate transfer member, and then secondarily transfers the toner image on the intermediate transfer member onto a recording material. 9. The forming method according to claim 8, wherein a color image is formed by sequentially superimposing a plurality of color toner images on an intermediate transfer member, and the color image is secondarily transferred collectively onto a recording material. 14. The image forming method according to any one of items 13. 8. The process cartridge for an image forming apparatus according to claim 1, comprising the electrophotographic photosensitive member and at least one of a charging unit, an exposure unit, a developing unit, and a transfer unit.

Images