JP4169726B2 - Electrophotographic photosensitive member, image forming apparatus, and process cartridge - Google Patents

Description

  The present invention is an electrophotographic photosensitive member that suppresses image flow due to adhesion of foreign matter that is likely to occur due to increased wear resistance of the electrophotographic photosensitive member, and realizes high durability, high image quality, and further stabilization of image quality, The present invention relates to an image forming apparatus and a process cartridge for the image forming apparatus.

  In recent years, the development of information processing system machines using electrophotography has been remarkable, and laser printers and digital copying machines that record information using light by converting information into digital signals have significantly improved print quality and reliability. . These laser printers and digital copiers that are rapidly spreading are required to have higher speed or smaller size simultaneously with higher image quality. Furthermore, recently, the demand for full-color laser printers and full-color digital copiers capable of full-color printing is rapidly increasing. When full-color printing is performed, it is necessary to superimpose toner images of at least four colors, and thus downsizing of the apparatus is particularly important.

  In order to reduce the size of the apparatus, it is necessary to reduce the diameter of the electrophotographic photosensitive member used for them. In particular, in the case of a tandem system effective for achieving both full color and high speed, since at least four photoreceptors are included in the apparatus, the degree of demand for reducing the diameter of the photoreceptor is very high. However, the reduction in the diameter of the photoconductor greatly reduces the life of the photoconductor, so it is essential to improve the wear resistance of the photoconductor.

  As electrophotographic photoreceptors used in these electrophotographic laser printers, digital copying machines, etc., those using organic photosensitive materials are generally widely applied for reasons such as cost, productivity and non-pollution. However, it was disadvantageous in terms of abrasion resistance as compared with inorganic photoreceptors. If the photoconductor is low in wear resistance, grounding will be noticeable when the photoconductor is used repeatedly, the sensitivity and charging stability will be reduced, and the image quality will be greatly reduced. become. However, in recent years, the wear resistance of a photoreceptor has been dramatically improved by curing the surface of an organic photoreceptor or laminating a protective layer containing a filler.

  However, even if it is possible to improve the abrasion resistance of the photoconductor by these methods, the occurrence of a new abnormal image is promoted, and the longevity of the photoconductor has not been achieved. . This is because foreign matter adhering to the surface becomes difficult to be removed due to the fact that the photoconductor is less likely to be worn, and thus abnormal images are liable to occur, and the electrophotographic photoconductor and an image forming apparatus using the same are highly developed. This is one of the biggest causes that hinders image quality and high durability.

  One of these abnormal images is image flow. This is because the discharge product generated by charging adheres to the surface of the photoconductor to reduce the resistance of the photoconductor surface, and the electric charge easily diffuses in the lateral direction, particularly in a high temperature and high humidity environment. The effect is noticeable. Since the photoconductor having poor abrasion resistance is easily removed by abrasion of the surface of the photoconductor even when these discharge products adhere to the photoconductor, image flow hardly occurs. However, as the wear resistance of the photoconductor improves, it becomes difficult to remove the discharge products adhering to the surface of the photoconductor, and they are further accumulated by repeated use. It was the biggest factor that greatly hindered the transformation.

  As a conventional technique for suppressing the image flow due to the adhesion of these discharge products, a method of heating a photosensitive member [Patent Document 1 (Japanese Patent Laid-Open No. 1-191883), Patent Document 2 (Japanese Patent Laid-Open No. 1-206386). Patent Document 3 (Japanese Patent Laid-Open No. 1-233474, etc.)] and a method of adding an antioxidant to the photosensitive layer [Patent Document 4 (Japanese Patent Laid-Open No. 59-136744), Patent Document 5 (Japanese Patent Laid-Open No. 2-64549). Patent Document 6 (Japanese Patent Laid-Open No. 2-64550), Patent Document 7 (Japanese Patent Laid-Open No. 8-292585, etc.)]. In particular, the method of dehumidifying the photosensitive member by heating is very effective for suppressing the image flow.

  However, in order to heat the photosensitive member, it is necessary to enclose a heater in the photosensitive member or the image forming apparatus. Therefore, an increase in the size of the apparatus cannot be avoided, and in particular, a tandem in which at least four photosensitive members are included. It has been difficult to apply to an image forming apparatus of the type. In addition, since it is necessary to constantly heat the photoconductor, there is a problem that causes a significant increase in power consumption. Furthermore, in the case of a small-diameter photoconductor that has become the mainstream in recent years, it has been difficult to enclose a heater in spite of the fact that higher durability is required. On the other hand, the method of adding an antioxidant to the surface of the photoconductor is effective in suppressing the deterioration of the electrostatic properties of the photoconductor due to ozone or NOx gas generated by charging, but the discharge adhering to the surface of the photoconductor. Actually, no effect was obtained on the product. As described above, the influence of the discharge products adhering to the surface of the photoconductor on the image flow increases with the improvement of the wear resistance of the photoconductor, and the conventional technology has many side effects and has a sufficient suppression effect. No high resolution and high durability have been realized.

  Other causes of abnormal images include adhesion of toner external additives and paper dust. This is because the foreign matter adhered to the surface of the photoconductor is accumulated every time it is used repeatedly, so that innumerable spots may appear in the image in the future, or they may cause image flow due to moisture intake. . In the prior art, attempts have been made to improve the releasability of the surface of the photoreceptor by reducing the friction coefficient and surface energy of the surface of the photoreceptor. For example, fluorine-modified silicone oil [Patent Document 8 (Japanese Patent Laid-Open No. 07-295248), Patent Document 9 (Japanese Patent Laid-Open No. 07-301936), Patent Document 10 (Japanese Patent Laid-Open No. 08-082940)] or silicone resin fine particles [Patent Document 11 (Japanese Patent Laid-Open No. 07-128872), Patent Document 12 (Japanese Patent Laid-Open No. 10-254160)], fluorine-containing resin fine particles [Patent Document 13 (Japanese Patent Laid-Open No. 63-65449), etc. are disclosed. Yes.

  However, although these methods can greatly reduce the friction coefficient and the surface energy at the initial stage, they are rapidly increased by repeated use, and the sustainability of the effect is extremely poor. As described above, the friction coefficient and the surface energy suddenly increase due to repeated use. One of the factors is the adhesion of discharge products generated by charging. When the discharge product adheres to the surface of the photoconductor, the accumulation rate of the discharge product on the surface of the photoconductor increases, and the adhesion between the photoconductor and the toner or paper powder increases. The effect of image flow will increase significantly. As described above, the discharge product has a great adverse effect on the improvement of the image quality of the photoconductor, and unless the influence is reduced, it is very difficult to improve the durability of the photoconductor, and it has not been realized yet. Is the actual situation.

  On the other hand, an attempt has been made to improve the releasability by roughening the surface of the photoreceptor. For example, a method [Patent Document 14 (Japanese Patent Laid-Open No. 2001-66814)] is disclosed in which a crest and a trough are regularly formed in a direction having an angle with the axial direction of the photoreceptor on the surface of the photoreceptor. . However, although this method has an effect of improving the releasability, it does not mention image flow caused by discharge products. In the present invention, even if the surface has irregularities, the effect is insufficient, and it is difficult to obtain the effect unless the linear scratches having the concave shape intersect at least from two directions. The structure and effect are completely different.

  Many other attempts have been made to roughen the photosensitive layer. For example, a photoconductor [Patent Document 15 (Patent No. 29987922)] in which a vacuum thin film is formed on a photoconductive photosensitive layer whose surface is roughened by innumerable linear scratches intersecting each other is disclosed. Yes. The roughening method is consistent with the present invention, but the main purpose is to form a vacuum thin film on the photoconductive photosensitive layer having linear scratches and to improve their adhesive strength, and intersect. The object, configuration, and effects are completely different from the present invention, which is mainly intended to form linear scratches on the outermost surface of the photosensitive member to suppress image flow.

Thus, in recent years, the wear resistance of organic photoconductors has been dramatically improved, but at the same time as the improvement in wear resistance has been realized, the image flow due to the discharge products and foreign matter adhering that has become apparent. In the case of an abnormal image such as the above, foreign matter tends to remain on the surface of the photosensitive member if it is intended to increase the abrasion resistance of the photosensitive member, and the abrasion resistance of the photosensitive member is sacrificed if such foreign matter is removed from the surface of the photosensitive member. Therefore, it has been very difficult to achieve both improvement in wear resistance and suppression of abnormal images. Even if the photoconductor has high wear resistance, abnormal images are generated at an early stage, which does not mean that the photoconductor and the image forming apparatus using the photoconductor are highly durable. While maintaining the wear resistance of the photoconductor, it is possible to suppress the image flow due to the adhesion of discharge products to the surface of the photoconductor, and to achieve both the wear resistance of the photoconductor and higher image quality as well as stabilization of the image quality. This is the biggest problem in realizing high durability of the body and the image forming apparatus using them.
Japanese Patent Laid-Open No. 1-191883 JP-A-1-206386 JP-A-1-233474 JP 59-136744 A Japanese Patent Laid-Open No. 2-64549 Japanese Patent Laid-Open No. 2-64550 JP-A-8-292585 JP 07-295248 A Japanese Patent Application Laid-Open No. 07-301936 Japanese Patent Application Laid-Open No. 08-082940 Japanese Patent Laid-Open No. 07-128772 Japanese Patent Laid-Open No. 10-254160 JP-A-63-65449 JP 2001-66814 A Japanese Patent No. 2987922

  An abnormal image such as an image flow that has been manifested by improving the wear resistance of the photoconductor is the biggest problem that hinders the high durability of the image forming apparatus. There is a trade-off between the wear resistance of the photoconductor and the occurrence of abnormal images due to foreign matter adhering to the surface of the photoconductor, and there is no significant effect on the wear resistance of the photoconductor. There has been a strong demand for means that can suppress image flow. An object of the present invention is to find a method capable of improving the abrasion resistance of a photoconductor and at the same time suppressing the image flow due to adhesion of foreign substances such as discharge products, thereby improving durability and improving image quality and further stabilizing image quality. An object of the present invention is to provide an electrophotographic photosensitive member, an image forming apparatus, and a process cartridge for the image forming apparatus that realize both of them.

  In order to realize high durability of the electrophotographic photosensitive member, it is necessary to suppress the influence of the image flow due to the discharge product adhering to the surface of the photosensitive member as well as improving the wear resistance as described above. If either of these is missing, high durability will not be realized. Conventionally, as the wear resistance of the photoconductor is improved, discharge products are likely to remain on the surface of the photoconductor, and the removal of these discharge products sacrifices the wear resistance of the photoconductor. The improvement of wear resistance and the stabilization of image quality due to the removal of discharge products are in a trade-off relationship and it is very difficult to achieve both.

  As a result of intensive studies, the present inventors have found that the image flow due to the discharge products adhering to the surface of the photoconductor is affected by the shape of the photoconductor surface, and satisfying the following constituent requirements, It has been found that image flow due to adhesion of discharge products can be suppressed while enhancing wear resistance, and the present invention has been completed.

(1) In an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support , a protective layer is formed on the surface of the electrophotographic photosensitive member, and the protective layer is cured by heating or light energy irradiation, Innumerable linear shapes that are insoluble in an organic solvent, have an elastic displacement rate τe defined by the following equation of the surface of the electrophotographic photosensitive member of 40% or more, and intersect the surface of the electrophotographic photosensitive member. An electrophotographic photosensitive member characterized in that scratches are uniformly formed.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100
( 2 ) The electrophotographic photosensitive member according to ( 1), wherein an average value of the width of the linear scratch is 10 μm or less.
( 3 ) The electrophotographic photosensitive member according to any one of (1) to ( 2 ), wherein 80% or more of the crossing angle of the linear scratches is 135 degrees or less.
( 4 ) A direction perpendicular to the surface movement direction of the electrophotographic photosensitive member is defined as a reference line, and it is defined as a distance from the intersection of the reference line and the linear scratch to the intersection of the linear scratch adjacent thereto and the reference line. The electrophotographic photosensitive member according to any one of (1) to ( 3 ), wherein an interval between the linear scratches is 100 μm or less as an average value.
( 5 ) The electrophotographic photosensitive member according to any one of (1) to ( 4 ), wherein an average value of the depth of the linear scratch is 0.5 μm or less.
(6) Dynamic hardness of the surface of the electrophotographic photosensitive member (DH) is, in the measurement using the 115 ° triangular pyramid indenter (Berkovich 115 indenter), above, wherein the at 22 least (1) to (5 The electrophotographic photoreceptor according to any one of 1).
( 7 ) The protective layer ( 1 ) to ( 6 ), wherein the protective layer comprises a layer obtained by curing at least a radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a charge transport structure. The electrophotographic photosensitive member according to any one of the above.
(8) is in the charge transport structure radical-polymerizable monomer having no three or more functional groups, according to (7), wherein the radical polymerizable compound having a charge transport structure is a monofunctional Electrophotographic photoreceptor.
(9) the ratio of molecular weight to the number of functional groups in the trifunctional or higher radical polymerizable monomer having no charge transport structure (molecular weight / number of functional groups) of the which is characterized in that 250 or less (7) to (8 ).
( 10 ) The functional group of the radically polymerizable monomer having no charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group, according to any one of ( 7 ) to ( 9 ), Electrophotographic photoreceptor.
( 11 ) The electron according to any one of ( 7 ) to ( 10 ), wherein the functional group of the radical polymerizable compound having the charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group. Photoconductor.
( 12 ) Any one of the above (1) to ( 11 ), wherein the surface of the electrophotographic photosensitive member contains at least one of a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound. An electrophotographic photoreceptor according to any one of the above.
( 13 ) The protective layer according to any one of ( 1 ) to ( 11 ) above, wherein the protective layer has a functional group in the silicone compound, fluorine compound, and long-chain alkyl group-containing compound, and is cured by heating or light energy irradiation. The electrophotographic photosensitive member according to any one of the above.
( 14 ) In an image forming apparatus that forms an image by sequentially repeating at least charging, exposure, development, transfer, and cleaning steps on the electrophotographic photosensitive member, the electrophotographic photosensitive member is the above (1) to ( 13 ). An image forming apparatus comprising the electrophotographic photosensitive member according to any one of the above.
( 15 ) The image forming apparatus includes a plurality of electrophotographic photosensitive members corresponding to developing units that hold a plurality of toners having different colors, so that at least charging, exposure, development, and transfer processes are performed in parallel. The image forming apparatus according to ( 14 ), wherein the image forming apparatus is a tandem type image forming apparatus.
( 16 ) The image forming apparatus according to any one of ( 14 ) to ( 15 ), wherein the electrophotographic photosensitive member is charged using a charging roller during the charging.
( 17 ) The image forming apparatus as described in any one of ( 14 ) to ( 16 ) above, wherein in the image forming apparatus, spherical or substantially spherical toner is used during the development.
( 18 ) The image forming apparatus according to any one of ( 14 ) to ( 17 ), wherein in the image forming apparatus, the image is transferred to paper through an intermediate transfer member or an intermediate transfer belt at the time of the transfer.
( 19 ) The image forming apparatus according to any one of ( 14 ) to ( 18 ), wherein cleaning is performed using a cleaning blade during the cleaning.
( 20 ) The image forming apparatus ( 14 ), wherein the image forming apparatus includes means for attaching at least one of a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound to the surface of the electrophotographic photosensitive member. ( 19 ) The image forming apparatus according to any one of ( 19 ).
( 21 ) The image forming apparatus includes any one of ( 14 ) to ( 20 ), characterized in that it includes means for forming innumerable linear scratches that intersect each other on the surface of the electrophotographic photosensitive member. The image forming apparatus described.
( 22 ) At least the electrophotographic photosensitive member is provided in a process cartridge for an image forming apparatus having a structure that is detachable from the main body of the image forming apparatus, and the electrophotographic photosensitive member is (1) to ( 13 ). A process cartridge for an image forming apparatus using the electrophotographic photosensitive member according to any one of the above.

  According to the present invention, the elastic displacement rate τe is 40% or more and the linear scratches intersecting the surface thereof are formed, so that the wear resistance of the photoreceptor is improved, and at the same time, the discharge product becomes the photoreceptor. Even if it adheres to the surface, it is possible to suppress the image flow. Conventionally, when the wear resistance of the photosensitive member is improved, it is difficult to remove the discharge products on the surface, and thus there is a tendency that image flow is likely to occur. However, the present invention makes it possible to achieve both of them. In addition, it has become possible to extend the life of the photosensitive member and the image forming apparatus using the photosensitive member. In addition, since linear scratches intersecting each other are formed on the surface of the photoconductor, the cleaning performance is improved even when a substantially spherical toner is used, and it is possible to obtain a further effect on image quality improvement. It was.

  The discharge product is considered to be generated by ionic species generated by charging and moisture in the atmosphere. These adhere to the surface of the photoreceptor and further draw in moisture in the atmosphere, thereby It is believed that surface resistance decreases and image bleed occurs. Therefore, if the discharge products adhering to the surface of the photosensitive member are removed by cleaning, it is possible to suppress the image flow. However, it becomes very difficult to remove discharge products as the wear resistance of the photoreceptor surface increases. The present invention makes it difficult to generate an image flow even if a discharge product adheres to the surface of a photoreceptor.

  The image flow occurs at high temperature and high humidity due to the discharge product adhering to the surface of the photoconductor, because the resistance of the portion where the discharge product adheres rapidly decreases, and the charge transferred from the charge generation layer It is considered that the charge is diffused in the lateral direction when it reaches the surface and the electrostatic latent image is blurred. That is, it is considered that the larger the area where the discharge product is attached, the wider the charge diffusion area and the greater the degree of image flow. Therefore, in order to suppress the image flow, it is preferable to reduce the adhesion amount of the discharge product, but it is very difficult when the wear resistance of the photoreceptor is increased. In the present invention, even if the discharge product adheres to the surface of the photosensitive member, the adhesion region is finely divided, and the image diffusion is suppressed by keeping the electric charge diffusion in a small region that does not affect the image. .

The following is a description of the claims of the present invention.
(1) In an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support, the elastic displacement rate τe defined by the following equation of the surface of the electrophotographic photosensitive member is 40% or more, and the electrophotographic photosensitive member An infinite number of linear scratches that intersect each other are uniformly formed on the surface of the body.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100

By setting the elastic displacement rate τe defined by the above equation to be 40% or more, the stress on the surface of the photoreceptor is relieved, so that a remarkable improvement in wear resistance can be realized. However, this method alone makes it difficult to remove discharge products, and image flow occurs early.
In the present invention, innumerable linear scratches are formed on the surface of the photoreceptor. As a result, the discharge product adhering to the surface of the photosensitive member is confined in the concave portion of the linear scratch during cleaning, and the discharge product in the portion without the linear scratch is easily removed.

  In this way, when discharge products are confined to linear scratches on the surface of the photoreceptor, charge diffusion is mainly limited to the linear scratches, thereby greatly reducing the effect of image flow. It becomes possible to make it. In addition, when the surface of the photoreceptor has a linear scratch, the contact area with the cleaning blade is reduced as compared with a smooth surface without a scratch, so that the effect of improving the cleaning property of the discharge product can be obtained. . In particular, the surface of the photoconductor having an elastic displacement rate τe defined by the above equation of 40% or more improves the wear resistance, but the cleaning blade tends to turn over, and cleaning failure often occurs. In the present invention, the contact area between the cleaning blade and the photosensitive member is reduced, so that the turning of the blade is suppressed, and an effect is also obtained for high cleaning stability. Further, since the elastic displacement rate τe defined by the above equation on the surface of the photoreceptor is 40% or more, the stress can be relieved, so that the chipping of the linear scratch portion can be reduced, and the scratch caused thereby. It is also possible to prevent the increase in wear and the promotion of wear.

  However, in the case where the linear scratches are not in a shape that intersects each other as in the present invention, but in a shape in only one direction, the writing lines parallel to the direction of the linear scratches do not diffuse charges laterally. Because it is suppressed, it is possible to suppress the image flow, but for the writing line perpendicular to the direction of the linear scratch, it promotes the diffusion of charges along the scratch, so that the characters Becomes fat and a decrease in resolution is recognized. In this way, when the linear flaw is in one direction, the direction of the linear flaw is generated in the image flow, which is not sufficient to suppress the image flow. By crossing the linear scratches from at least two directions, it is possible to suppress the diffusion of charges with respect to the writing lines in all directions, and it is possible to suppress the image flow.

(2) The electrophotographic photosensitive member according to (1), wherein a protective layer is formed on the surface of the electrophotographic photosensitive member.
Since the protective layer can be made thinner than the photosensitive layer, it is easy to obtain a photoreceptor having a surface with an elastic displacement rate τe defined by the above equation of 40% or more. In addition, since the film thickness can be reduced, it is excellent in dramatically improving the wear resistance without greatly affecting the residual potential and the like, and is particularly effective and useful in the present invention.

(3) The electrophotographic photosensitive member according to (1) or (2) above, wherein an average value of the width of the linear scratch is 10 μm or less.
As the width of the formed linear scratch is larger, the charge diffusion region becomes wider and the influence of image flow tends to increase. Further, if the width of the linear scratch is larger than necessary, a streak-like image defect may occur or an image defect due to accumulation of foreign matter may occur, which may reduce the effect of the present invention. By making the width of the linear scratch to be formed 10 μm or less, it is possible to suppress the influence thereof, to obtain a sufficient image flow suppressing effect, and to obtain a large effect in suppressing abnormal images. .

(4) The electrophotographic photosensitive member according to any one of (1) to (3), wherein 80% or more of the crossing angle of the linear scratches is 135 degrees or less.
As the crossing angle of linear flaws intersecting at least from two directions decreases, the image flaw-dependent dependency on the image flaw described in (1) increases, and the image flow suppression effect decreases. By forming 80% or more of the crossing angle of the linear scratches to be 135 degrees or less, it is possible to suppress image flow for lines and dots in all directions.

(5) A direction orthogonal to the surface movement direction of the electrophotographic photosensitive member is defined as a reference line, and is defined as a distance from the intersection of the reference line and the linear scratch to the intersection of the linear scratch adjacent thereto and the reference line. The electrophotographic photosensitive member according to any one of (1) to (4), wherein an interval between the linear scratches is 100 μm or less as an average value.
As the interval between the linear scratches becomes wider, the effect of suppressing the image flow is reduced. Therefore, it is necessary to form the linear scratches uniformly on the entire surface of the photoreceptor. In the present invention, the interval between the linear scratches is a reference line in a direction orthogonal to the surface movement direction of the photosensitive member, and an intersection between the reference scratch and the linear scratch and an adjacent linear scratch and the reference line. If the average value is set to 100 μm or less, linear flaws can be uniformly formed, and the effect of suppressing image blur is sufficiently exhibited and effective.

(6) The electrophotographic photosensitive member according to any one of (1) to (5), wherein an average depth of the linear scratches is 0.5 μm or less.
When the depth of the linear scratch becomes deep, foreign matter easily enters the dent portion of the scratch and is difficult to remove, which may cause image defects due to filming and foreign matter adhesion. When the average value of the depths of the linear scratches is 0.5 μm or less, it is possible to obtain a sufficient image blur suppression effect without side effects due to the influence thereof.

(7) The dynamic hardness (DH) of the surface of the electrophotographic photosensitive member is 22 or more in the measurement using a 115 ° triangular cone indenter (Belkovic 115 indenter). The electrophotographic photoreceptor according to any one of 1).
Since the dynamic hardness (DH) of the photoreceptor surface is 22 or more, not only the abrasion resistance of the photoreceptor is further improved, but also the formed linear scratch is stably maintained even after repeated use. The effect of the present invention can be obtained stably over a long period of time.

(8) The electrophotographic photosensitive member according to any one of (2) to (7), wherein the protective layer is cured by heating or light energy irradiation and is insoluble in an organic solvent.
Even when the elastic displacement rate τe defined by the above equation on the surface of the photoreceptor is 40% or more, it is advantageous to improve the wear resistance when cured by heating or light energy irradiation. In the present invention, it is possible to select a means for forming a linear flaw before curing and then curing, which has a great merit in terms of productivity and stability of effects.

(9) The protective layer (2) to (8), wherein the protective layer comprises a layer obtained by curing at least a radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a charge transport structure. The electrophotographic photosensitive member according to any one of the above.
By further curing radical polymerizable monomers that do not have a charge transporting structure and radical polymerizable compounds that have a charge transporting structure, it is possible to further ensure both improvement of wear resistance and stabilization of residual potential and sensitivity. Can do.
When the radical polymerizable monomer having no charge transporting structure is cured alone, it becomes difficult to transfer the charge to the surface, a remarkable residual potential rises, and the image density becomes unstable. In this case, this problem can be improved by adding a low-molecular charge transport material as a charge transport material, but the low-molecular charge transport material may precipitate on the surface after curing, and an abnormal image is generated. There is a fear.

(10) The radical polymerizable monomer having no charge transport structure is trifunctional or more, and the radical polymerizable compound having the charge transport structure is monofunctional. Electrophotographic photoreceptor.
When the radical polymerizable monomer having no charge transporting structure is trifunctional or more, a protective layer having a dense and homogeneous three-dimensional network structure can be formed, and a high elastic displacement rate with a high crosslinking density and Since a highly hard film can be formed, it is advantageous for improving wear resistance. On the other hand, since the radical polymerizable compound having a charge transporting structure is monofunctional, there is little influence of residual potential increase and sensitivity deterioration, and there are few irregularities on the film surface, which is advantageous for improving image quality stability and production stability. It is.

(11) The above-mentioned (9) to (10), wherein the ratio of the molecular weight to the number of functional groups (molecular weight / number of functional groups) in the tri- or higher functional radical polymerizable monomer having no charge transport structure is 250 or less. ).
The ratio of molecular weight to the number of functional groups (molecular weight / number of functional groups) in the trifunctional or higher functional radical polymerizable monomer having no charge transport structure is 250 or less, so that the crosslink density is increased and the protective layer has a higher elastic displacement rate. Can be obtained. At the same time, it is effective in increasing the hardness, which makes it possible to maintain high wear resistance.

(12) The functional group of the radical polymerizable monomer having no charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group, according to any one of (9) to (11), Electrophotographic photoreceptor.
Since the functional group of the radical polymerizable monomer having no charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group, the wear potential is improved and the residual potential is reduced and the stability over time is improved. This is advantageous in improving image quality and suppressing image blur due to ozone and NOx.

(13) The electron according to any one of (9) to (12), wherein the functional group of the radical polymerizable compound having the charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group. Photoconductor.
Since the functional group of the radically polymerizable compound having a charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group, the wear potential is improved, and at the same time, the residual potential is reduced and the stability over time is improved. This is advantageous for improvement, suppression of image blur due to ozone and NOx, and the like.

(14) Any one of (1) to (13) above, wherein the surface of the electrophotographic photosensitive member contains at least one of a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound. An electrophotographic photoreceptor according to any one of the above.
By containing at least one of a silicone compound, a fluorine compound, and a long chain alkyl group-containing compound, the coefficient of friction on the surface of the photoreceptor is reduced and the releasability is improved. It is effective for improving the performance. Furthermore, since the surface is roughened by having linear scratches, the durability of the friction coefficient reduction effect is improved. In particular, the adhesion of discharge products is one of the causes for increasing the friction coefficient of the surface of the photosensitive member. Therefore, by confining them in the linear scratches, the durability of the effect of reducing the friction coefficient is increased, thereby causing foreign matter. The influence on the image quality can be greatly reduced.

(15) The protective layer has a functional group in a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound, and is cured by heating or light energy irradiation. The electrophotographic photosensitive member according to any one of the above.
The silicone-based compound, the fluorine-based compound, and the long-chain alkyl group-containing compound have a functional group and are hardened by heating or light energy irradiation, so that they hardly ooze out on the surface of the photoreceptor, (14) The stability of the mold release effect described in 1) is remarkably improved, and since it is cured together, it is possible to obtain further effects in improving the image quality stability without lowering the wear resistance due to crosslinking inhibition. Become.

(16) In an image forming apparatus for forming an image by sequentially repeating at least charging, exposure, development, transfer, and cleaning steps on the electrophotographic photosensitive member, the electrophotographic photosensitive member is the above (1) to (15). An image forming apparatus comprising the electrophotographic photosensitive member according to any one of the above.
By using the photoconductor of the present invention, there is provided an image forming apparatus which has both high wear resistance and does not cause image flow even in a high temperature and high humidity environment, and realizes both durability and image quality stability. It becomes possible.

(17) The image forming apparatus includes a plurality of electrophotographic photosensitive members corresponding to developing units that hold a plurality of toners having different colors, so that at least charging, exposure, development, and transfer processes are performed in parallel. The image forming apparatus according to (16), wherein the image forming apparatus is a tandem type image forming apparatus.
By using the photoconductor of the present invention, both high image quality and high durability can be achieved, thereby enabling the photoconductor to be reduced in diameter. Therefore, it is necessary to enclose a plurality of photoconductors, which greatly contributes to the miniaturization of the tandem type image forming apparatus that has been difficult to miniaturize. In addition, this makes it possible to increase the speed of full-color printing, and it is possible to obtain an image forming apparatus that simultaneously realizes high image quality, high stability, high durability, and high speed.

(18) The image forming apparatus according to any one of (16) to (17), wherein in the image forming apparatus, the electrophotographic photosensitive member is charged using a charging roller during the charging.
The charging roller generates much less ozone and NOx than corona charging, and can reduce the effects of image blur due to ozone and NOx gas. However, the amount of discharge product adhesion increases on the contrary. Become. By using the photoconductor of the present invention and using a charging roller as the charging means, it is possible to suppress the influence on the image due to the adhesion of the discharge product, so that the image flow caused by the discharge product and the ozone or NOx gas It is possible to reduce the influence of image blur at the same time, which is very excellent in image quality stability.

(19) The image forming apparatus according to any one of (16) to (18), wherein a spherical or substantially spherical toner is used during the development in the image forming apparatus.
Use of spherical or nearly spherical toner improves transfer efficiency and is very effective for improving image quality. However, the spherical shape significantly reduces the cleaning performance of the toner, which causes problems in use. Yes. In the present invention, the formation of linear scratches intersecting the surface of the photoreceptor makes it possible to suppress the rolling of the spherical toner during cleaning, so that the effect of greatly improving the toner cleaning properties can be obtained. . When the linear scratches on the surface of the photoreceptor are only in one direction, the rolling of the toner cannot be sufficiently suppressed and satisfactory cleaning properties cannot be obtained, but linear scratches intersecting at least from two directions are formed. This makes it possible to completely suppress the movement of the toner and further improve the releasability, so that the toner can be remarkably improved and the spherical toner can be fully used, thereby improving the image quality and stabilizing the image quality. It is possible to obtain a remarkable effect on the conversion.

(20) The image forming apparatus as described in any one of (16) to (19) above, wherein in the image forming apparatus, the image is transferred onto paper via an intermediate transfer member or an intermediate transfer belt during the transfer.
By transferring to paper via an intermediate transfer member or an intermediate transfer belt at the time of transfer, the effect of paper dust can be suppressed because the paper does not directly contact the photosensitive member. Further, in the process of transferring the toner from the photosensitive member to the intermediate transfer member or the intermediate transfer belt, the toner remains without being transferred from the photosensitive member, and image defects such as voids are likely to occur. In the present invention, since linear scratches intersecting the surface of the photosensitive member are formed, a release effect can be obtained, and excessive adhesion between the photosensitive member and the toner can be reduced, whereby an intermediate transfer member is obtained. Alternatively, transferability to the intermediate transfer belt can be improved. As a result, image defects such as voids can be suppressed, and high image quality can be achieved. Further, since the transfer efficiency can be improved, the load applied to the cleaning can be reduced, and the cleaning efficiency can be improved.

(21) In the image forming apparatus according to any one of (16) to (20), the cleaning is performed using a cleaning blade during the cleaning.
The cleaning step in the present invention is required not only to clean only the toner particles but also to remove the discharge products adhering to the photoreceptor and confine them in the linear scratches. In this case, a cleaning blade that is always in contact with the surface of the photoreceptor is more effective than the cleaning brush. By using the cleaning blade, an effect can be obtained for cleaning the discharge product attached to the surface of the photosensitive member, and it is also suitable and effective for confining the discharge product in the formed linear scratch. It is advantageous in obtaining.

(22) The image forming apparatus according to (16) to (16), wherein the image forming apparatus includes means for attaching at least one of a silicone compound, a fluorine compound, and a long chain alkyl group-containing compound to the surface of the electrophotographic photosensitive member. (21) The image forming apparatus according to any one of (21).
By attaching a compound containing these slipping components to the photoreceptor surface, the friction coefficient of the photoreceptor surface is reduced, thereby improving releasability, reducing adhesion of foreign matter, reducing the amount of wear, etc. Many effects can be obtained, but if it adheres excessively, it has side effects that cause image defects such as a reduction in resolution. In the present invention, since linear scratches intersecting at least two directions are formed on the surface of the photoreceptor, even if compounds containing these slipping components adhere excessively, they enter the linear scratches, resulting in a decrease in resolution. It is possible to suppress the side effects of image defects such as these. Furthermore, it is possible to increase the sustainability of the friction coefficient reduction effect.

(23) Any one of (16) to (22) above, wherein the image forming apparatus includes means for forming innumerable linear scratches intersecting each other on the outermost surface of the electrophotographic photosensitive member. The image forming apparatus described in 1.
Even if the abrasion resistance of the photosensitive member is improved, it is difficult to completely eliminate the wear amount. Therefore, if it wears over time, the formed linear scratch will eventually disappear due to wear, and the sustainability of the effect of suppressing image blur will thereby decrease. Therefore, by forming linear scratches on the surface of the photoreceptor over time in the image forming apparatus, it is possible to maintain the effect of suppressing the image flow semi-permanently and to further improve the stabilization of the image quality of the photoreceptor. . In addition, by adding a process of forming linear scratches over time of use, a reface effect on the surface of the photoconductor, that is, an effect of removing filming matter adhering to the surface of the photoconductor, can be obtained. can get. In the present invention, the scratch formed on the surface of the photosensitive member by contact with the developer, paper, cleaning blade, etc. due to repeated use of the photosensitive member is also linear, and can be handled as the linear scratch of the present invention. . However, in this case, the linear scratch formed by the contact of the developer, paper, cleaning blade or the like is in one direction, and that alone is not sufficient as an image blur prevention effect. In some cases, the image flow is enhanced in one direction, which may cause a significant reduction in resolution. In the present invention, since the line flaws intersect each other, the image flow can be suppressed even when writing in any direction. In this case, the lines formed by the developer, paper, cleaning blade, etc. This is accomplished by forming another linear wound having a different angle than the wound.

(24) In the image forming apparatus, at least the electrophotographic photosensitive member is provided in a process cartridge for an image forming apparatus having a structure that is detachable from the main body of the image forming apparatus, and the electrophotographic photosensitive member is A process cartridge for an image forming apparatus, wherein any one of the electrophotographic photosensitive members described in any one of 1) to (15) is used.
The photoreceptor of the present invention can dramatically improve durability by having both wear resistance and image quality stability. However, if the service life is increased in this way, maintenance around the photoconductor and replacement of consumables are necessary.In addition, a linear scratch is formed on the surface of the photoconductor, or a member for forming a linear scratch is required. There is also a need for replacement. In this case, by providing the photosensitive member in the process cartridge having a structure that is detachable from the main body of the image forming apparatus, maintenance and replacement thereof are facilitated. Thereby, repeated use over a longer period of time becomes possible.

  As described above, a photoconductor with improved photoconductor wear resistance has been subjected to intense image flow in a high-temperature and high-humidity environment due to discharge products adhering to the photoconductor surface, improving the photoconductor wear resistance. And stabilization of image quality have not been realized. In the present invention, even if a discharge product adheres to the surface of the photoconductor, it is not manifested as an image flow by narrowing a low resistance region, thereby improving both the wear resistance of the photoconductor and stabilizing the image quality. Was able to be realized. Furthermore, the present invention also provides an effect of simultaneously improving transfer efficiency and cleaning performance, and is very effective for improving image quality. According to the present invention, it is possible to suppress the occurrence of abnormal images such as image flow while maintaining the abrasion resistance of the photosensitive member, and it is possible to improve the transfer efficiency and the cleaning property at the same time. It has become possible to provide an electrophotographic photosensitive member that realizes all of durability, high image quality, and stable image quality, and an image forming apparatus using the same.

The present invention is described in detail below.
First, the electrophotographic photosensitive member used in the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view showing the layer structure of the electrophotographic photosensitive member of the present invention. A photosensitive layer 33 mainly composed of a charge generating material and a charge transporting material is sequentially provided on a conductive support 31. .
FIG. 2 is a cross-sectional view showing the layer structure of the electrophotographic photosensitive member of the present invention. On the conductive support 31, a charge generation layer 35 containing a charge generation material as a main component and a charge transport material as a main component. A charge transport layer 37 is sequentially provided.
FIG. 3 is a cross-sectional view showing the layer structure of the electrophotographic photosensitive member of the present invention. On the conductive support 31, a photosensitive layer 33 and a protective layer 39 mainly composed of a charge generating material and a charge transporting material are sequentially formed. Is provided.
FIG. 4 is a cross-sectional view showing the layer structure of the electrophotographic photosensitive member of the present invention. On the conductive support 31, a charge generation layer 35 containing a charge generation material as a main component and a charge transport material as a main component. A charge transport layer 37 and a protective layer 39 are sequentially provided.
FIG. 5 is a cross-sectional view showing the layer structure of the electrophotographic photosensitive member of the present invention. On the conductive support 31, a charge transport layer 37 containing a charge transport material as a main component and a charge generation material as a main component. A charge generation layer 35 and a protective layer 39 are sequentially provided.

Examples of the conductive support 31 include those having a volume resistance of 10 ¹⁰ Ω · cm or less, for example, metals such as aluminum, nickel, chromium, nichrome, copper, gold, silver, platinum, tin oxide, indium oxide, etc. The metal oxide of the above is coated with film or cylindrical plastic or paper by vapor deposition or sputtering, or a plate made of aluminum, aluminum alloy, nickel, stainless steel or the like and extruded by drawing or drawing. After pipe formation, surface treatment pipes such as cutting, superfinishing, and polishing can be used. Further, an endless nickel belt or an endless stainless steel belt disclosed in Japanese Patent Application Laid-Open No. 52-36016 can also be used as the conductive support 31.

  In addition, a material obtained by dispersing conductive powder in an appropriate binder resin and coating it on the support can also be used as the conductive support 31 of the present invention. Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. It is done. The binder resin used at the same time is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, Examples thereof include thermoplastic, thermosetting resins, and photocurable resins such as melamine resin, urethane resin, phenol resin, and alkyd resin. Such a conductive layer can be provided by dispersing and coating these conductive powder and binder resin in a suitable solvent such as tetrahydrofuran, dichloromethane, methyl ethyl ketone, and toluene.

  Furthermore, it is electrically conductive by a heat-shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive support 31 of the present invention.

  Next, the photosensitive layer will be described. The photosensitive layer may be a single layer or a structure in which a plurality of layers are laminated. First, the case of a laminated structure composed of the charge generation layer 35 and the charge transport layer 37 will be described. Each of the charge generation layer and the charge transport layer may be a single layer or a plurality of layers. Further, a charge transport layer may be formed on the charge generation layer, or vice versa.

First, the charge generation layer 35 will be described. The charge generation layer 35 is a layer mainly composed of a charge generation material, and a binder resin can be used in combination as necessary.
As the charge generation material, inorganic materials and organic materials can be used. Inorganic materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compounds, cadmium sulfide, cadmium sulfide-selenium, amorphous silicon, and the like. In amorphous silicon, dangling bonds that are terminated with hydrogen atoms or halogen atoms, or those that are doped with boron atoms, phosphorus atoms, or the like are preferably used.

  On the other hand, a known material can be used as the organic material. For example, a disazo pigment, an asymmetrical disazo pigment, a trisazo pigment, an azo pigment having a carbazole skeleton (described in JP-A-53-95033), an azo pigment having a distyrylbenzene skeleton (JP-A-53-133445), An azo pigment having a triphenylamine skeleton (described in JP-A-53-132347), an azo pigment having a diphenylamine skeleton, an azo pigment having a dibenzothiophene skeleton (described in JP-A-54-21728), a fluorenone skeleton An azo pigment having an oxadiazole skeleton (described in JP-A-54-12742), an azo pigment having a bis-stilbene skeleton (described in JP-A-54-22834) No. 17733), an azo face having a distyryl oxadiazole skeleton (Described in JP-A No. 54-2129), azo pigments such as azo pigments having a distyrylcarbazole skeleton (described in JP-A No. 54-14967), azulenium salt pigments, squaric acid methine pigments, perylene Pigments, anthraquinone or polycyclic quinone pigments, quinoneimine pigments, diphenylmethane and triphenylmethane pigments, benzoquinone and naphthoquinone pigments, cyanine and azomethine pigments, indigoid pigments, bisbenzimidazole pigments, and Examples thereof include phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine.

  In the formula, M (central metal) represents a metal or metal-free (hydrogen) element. M (center metal) mentioned here is H, Li, Be, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga , Ge, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ba, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, TI , La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, Pa, U, Np, Am, etc., or oxide, chloride It consists of two or more elements such as fluoride, fluoride, hydroxide and bromide. The central metal is not limited to these elements. The charge generation material having a phthalocyanine skeleton in the present invention may have at least a basic skeleton of the general formula (N), a substance having a multimeric structure such as a dimer or trimer, and a higher order high-order substance. It may have a molecular structure. Also, the basic skeleton may have various substituents.

  Of these various phthalocyanines, oxotitanium phthalocyanine having TiO as the central metal, metal-free phthalocyanine, chlorogallium phthalocyanine, and the like are particularly preferable in view of the photoreceptor characteristics. These phthalocyanines are known to have various crystal systems. For example, in the case of oxotitanium phthalocyanine, α, β, γ, m, Y type, etc., in the case of copper phthalocyanine, α, β, γ, etc. It has a polycrystal system. Even in the phthalocyanine having the same central metal, various properties change as the crystal system changes. It has been reported that the characteristics of photoreceptors using phthalocyanine pigments having these various crystal systems also change accordingly (Electrophotographic Society Vol. 29, No. 4, (1990)). Therefore, the selection of the crystal system of phthalocyanine is very important in terms of the characteristics of the photoreceptor, and Y-type oxotitanium phthalocyanine is particularly effective and useful for increasing the sensitivity. These charge generation materials can be used alone or as a mixture of two or more.

  Examples of the binder resin used for the charge generation layer 35 include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate resin, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, and poly-N-vinylcarbazole. And polyacrylamide. These binder resins can be used alone or as a mixture of two or more. In addition to the above-described binder resin, the charge generating layer may be formed of a polymer charge transport material described later (for example, JP-A 64-1728, JP-A 64-13061, JP-A 64-19049, JP-A-4-11627, JP-A-4-22014, JP-A-4-230767, JP-A-4-320420, JP-A-5-232727, JP-A-6- No. 234838, JP-A-6-234839, JP-A-6-295077, JP-A-7-56374, JP-A-7-325409, JP-A-9-80772, and JP-A-9-80783. JP-A-9-80784, JP-A-9-127713, JP-A-9-211877, JP-A-9-222740, JP-A-9-26519 JP, Hei 9-265201, JP-A No. 9-297419, JP-A No. 9-304956 JP) can be used. The amount of the binder resin used in the charge generation layer 35 is 0 to 500 parts by weight, preferably 0 to 200 parts by weight with respect to 100 parts by weight of the charge generation material. Moreover, various additives, such as leveling agents, such as a dimethyl silicone oil and a methylphenyl silicone oil, a sensitizer, and a dispersing agent, can be added as needed.

  As a method for forming the charge generation layer 35, a vacuum thin film manufacturing method and a casting method from a solution dispersion system can be largely mentioned. As the former method, a vacuum deposition method, a glow discharge decomposition method, an ion plating method, a sputtering method, a reactive sputtering method, a CVD method, or the like is used, and the above-described inorganic materials and organic materials can be satisfactorily formed. In addition, in order to provide a charge generation layer by the casting method described later, tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone together with the above-mentioned inorganic or organic charge generation material together with a binder resin as necessary. Disperse with a ball mill, attritor, sand mill, bead mill, etc. using a solvent such as cyclopentanone, anisole, xylene, methyl ethyl ketone, acetone, ethyl acetate, butyl acetate, etc. it can. The application can be performed using a conventionally known method such as a dip coating method, spray coating, bead coating, or ring coating method. The thickness of the charge generation layer provided as described above is suitably about 0.01 to 5 μm, preferably 0.05 to 2 μm.

The charge transport layer 37 can be formed by dissolving or dispersing at least a charge transport material and a binder resin in an appropriate solvent, and applying and drying the solution on the charge generation layer 35, for example.
Examples of the charge transport material include a hole transport material and an electron transport material. Examples of the electron transporting 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] thiophen-4-one, 1,3,7-tri Examples thereof include electron-accepting substances such as nitrodibenzothiophene-5,5-dioxide and diphenoquinone derivatives. 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. As hole transport materials, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives, triaryls Other known materials such as methane derivatives, 9-styrylanthracene derivatives, pyrazoline derivatives, divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, bisstilbene derivatives, enamine derivatives, and the like can be given. These hole transport materials can be used alone or as a mixture of two or more.

  Examples of the binder resin include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester resin, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate. , Polyvinylidene chloride, polyarylate resin, phenoxy resin, acrylic resin, methacrylic resin, polycarbonate resin, epoxy resin, melamine resin, urethane resin, silicone resin, fluorine resin, cellulose acetate resin, ethyl cellulose resin, etc. You may mix and use seed | species or more resin.

  For the charge transport layer 37, a polymer charge transport material having a function as a binder resin and a function as a charge transport material is also preferably used. When these polymer charge transport materials are contained in the charge transport layer, the protective layer is prevented from being dissolved into the protective layer because the low molecular charge transport material in the charge transport layer is not dissolved when the protective layer is laminated thereon. It becomes possible to reduce the influence of layer cross-linking inhibition, which is effective for improving the wear resistance. In the present invention, these polymer charge transport materials may be mixed with the aforementioned binder resin or low molecular charge transport material. As the polymer charge transport material, all known materials can be used, and in particular, a polycarbonate containing a triarylamine structure in the main chain and / or side chain is preferably used. Among these, polymer charge transport materials represented by the following formulas (I) to (X) are preferably used.

[Wherein, R ₁ , R ₂ and R ₃ are each independently a substituted and / or unsubstituted alkyl group or halogen atom, R ₄ is a hydrogen atom or a substituted and / or unsubstituted alkyl group, R ₅ , R ₆ is a substituted and / or unsubstituted aryl group, o, p and q are each independently an integer of 0 to 4, k and j are compositions (molar fractions), 0.1 ≦ k ≦ 1, 0 ≦ j ≦ 0.9 represents the number, n represents the number of repeating units and is an integer of 5 to 5000. X represents an aliphatic divalent group, a cycloaliphatic divalent group, or a divalent group represented by the following general formula. ]

（ａは１〜２０の整数、ｂは１〜２０００の整数、Ｒ₁₀₃、Ｒ₁₀₄は置換または無置換のアルキル基又はアリール基を表す）を表す。ここで、Ｒ₁₀₁とＲ₁₀₂、Ｒ₁₀₃とＲ₁₀₄は、それぞれ同一でも異なってもよい。］ (In the formula, R ₁₀₁ and R ₁₀₂ each independently represents a substituted and / or unsubstituted alkyl group, aryl group or halogen atom. L and m are integers of 0 to 4, Y is a single bond, and the number of carbon atoms. 1 to 12 linear, branched and / or cyclic alkylene groups, —O—, —S—, —SO—, —SO ₂ —, —CO—, —CO—O—Z—O—CO—. (Z represents an aliphatic divalent group) or

(A represents an integer of 1 to 20, b represents an integer of 1 to 2000, and R ₁₀₃ and R ₁₀₄ represent a substituted or unsubstituted alkyl group or aryl group). Here, R ₁₀₁ and R ₁₀₂ , and R ₁₀₃ and R ₁₀₄ may be the same or different. ]

(In the formula, R ₇ and R ₈ are substituted and / or unsubstituted aryl groups, Ar ₁ , Ar ₂ and Ar ₃ are the same or different arylene groups. X, k, j and n are represented by the general formula (I ) Same as)

Wherein R ₉ and R ₁₀ are substituted and / or unsubstituted aryl groups, Ar ₄ , Ar ₅ and Ar ₆ are the same or different arylene groups. X, k, j and n are represented by the general formula (I ) Same as)

Wherein R ₁₁ and R ₁₂ are substituted and / or unsubstituted aryl groups, Ar ₇ , Ar ₈ and Ar ₉ are the same or different arylene groups, and p is an integer of 1 to 5. X, k , J and n are the same as in the general formula (I).)

Wherein R ₁₃ and R ₁₄ are substituted and / or unsubstituted aryl groups, Ar ₁₀ , Ar ₁₁ and Ar ₁₂ are the same or different arylene groups, and X ₁ and X ₂ are substituted and / or unsubstituted ethylene groups. Or represents a substituted and / or unsubstituted vinylene group, wherein X, k, j and n are the same as those in formula (I).)

(Wherein R ₁₅ , R ₁₆ , R ₁₇ , R ₁₈ are substituted and / or unsubstituted aryl groups, Ar ₁₃ , Ar ₁₄ , Ar ₁₅ , Ar ₁₆ are the same or different arylene groups, Y ₁ , Y ₂ , Y ₃ represents a single bond, a substituted and / or unsubstituted alkylene group, a substituted and / or unsubstituted cycloalkylene group, a substituted and / or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group, and is the same X, k, j and n may be the same as those in the general formula (I).

(In the formula, R ₁₉ and R ₂₀ represent a hydrogen atom, a substituted and / or unsubstituted aryl group, and R ₁₉ and R ₂₀ may form a ring. Ar ₁₇ , Ar ₁₈ and Ar ₁₉ are the same. Or represents a different arylene group, wherein X, k, j and n are the same as those in formula (I).)

(Wherein R ₂₁ represents a substituted and / or unsubstituted aryl group, Ar ₂₀ , Ar ₂₁ , Ar ₂₂ , Ar ₂₃ represent the same or different arylene groups. X, k, j and n are represented by the general formula (I ) Same as)

(In the formula, R ₂₂ , R ₂₃ , R ₂₄ and R ₂₅ represent a substituted and / or unsubstituted aryl group, Ar ₂₄ , Ar ₂₅ , Ar ₂₆ , Ar ₂₇ and Ar ₂₈ represent the same or different arylene groups. X , K, j and n are the same as those in the general formula (I).)

Wherein R ₂₆ and R ₂₇ are substituted and / or unsubstituted aryl groups, Ar ₂₉ , Ar ₃₀ and Ar ₃₁ are the same or different arylene groups. X, k, j and n are represented by the general formula (I ) Same as)

  Hereinafter, some specific examples of the polycarbonate containing the triarylamine structure in the main chain and / or the side chain are shown below, but the present invention is not limited to these specific examples.

  These polymer charge transport materials having a triarylamine structure in the main chain or side chain are polymerized in the form of a homopolymer, a random copolymer, an alternating copolymer, or a block copolymer. And since these polymer charge transport materials have a role as a binder resin, it is necessary to have a film-forming ability. Therefore, the molecular weight is suitably 10,000 to 500,000, preferably 50,000 to 400,000, as the polystyrene-equivalent molecular weight Mw in the measurement by GPC.

  These polymer charge transport materials are disclosed in JP-A-8-269183, JP-A-9-71642, JP-A-9-104746, JP-A-9-272735, JP-A-11-29634, JP-A-11-29634. 9-235367, JP-A-9-87376, JP-A-9-110976, JP-A-9-268226, JP-A-9-221544, JP-A-9-227669, JP-A-9- No. 157378, JP-A-9-302084, JP-A-9-302085, and JP-A-2000-26590.

The content of the charge transport material is 20 to 300 parts by weight, preferably 40 to 150 parts by weight, per 100 parts by weight of the binder resin. However, when a polymer charge transport material is used, it can be used alone or in combination with other binder resins.
As the solvent used for coating the charge transport layer 37, the same solvent as the charge generation layer 35 can be used. Examples include solvents such as tetrahydrofuran, dioxane, dioxolane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, cyclopentanone, anisole, xylene, methyl ethyl ketone, acetone, ethyl acetate, butyl acetate, etc. And those that dissolve the binder resin well are suitable. These solvents may be used alone or in combination of two or more.

  A leveling agent, an antioxidant, a plasticizer, or the like can be added to the charge transport layer 37 as necessary. As leveling agents that can be used in combination, silicone oils such as dimethyl silicone oil and methyl phenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used, and the amount used is 100 weight of binder resin. About 0 to 1 part by weight per part is appropriate.

  Antioxidants that can be used in combination include phenolic compounds, hindered phenolic compounds, hindered amine compounds, paraphenylenediamines, hydroquinones, organic sulfur compounds, organic phosphorus compounds, benzophenones, salsylates, benzoates. All conventionally known antioxidants such as triazoles and quenchers (metal complex salts) can be used. Moreover, the effect may increase remarkably by mixing and adding 2 or more types of antioxidant, and it is effective. The amount used is suitably about 0 to 5% by weight with respect to 100 parts by weight of the binder resin. As plasticizers that can be used in combination, those used as plasticizers for general resins such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount used is based on 100 parts by weight of the binder resin. About 0 to 30 parts by weight is appropriate.

  The coating can be performed using a known method such as a dip coating method, a spray coat, a bead coat, or a ring coat method in the same manner as the charge generation layer 35, but the dip coating method is most preferably used. . The thickness of the charge transport layer 37 is about 5 to 50 μm, and preferably about 10 to 30 μm in terms of image characteristics such as resolution and background stains and electrical characteristics such as charging potential and sensitivity.

  Next, the case where the photosensitive layer has a single layer structure 33 will be described. The photosensitive layer 33 is formed by dissolving or dispersing the above-described charge generation material, charge transport material, binder resin, etc. in an appropriate solvent, and coating and drying this on a conductive support. As the charge generation material and the charge transport material, the materials described above for the charge generation layer 35 and the charge transport layer 37 can be used. As the binder resin, in addition to the resin mentioned in the charge transport layer 37, the resin mentioned in the charge generation layer 35 may be mixed and used. In addition, the above-described polymer charge transporting material can be favorably used as the binder resin. The amount of the charge generating material with respect to 100 parts by weight of the binder resin is preferably 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, and the amount of the charge transporting material is preferably 0 to 190 parts by weight, and more preferably. 50 to 150 parts by weight. The photosensitive layer is obtained by dissolving or dispersing a charge generating material and a binder resin together with a charge transporting material in a solvent such as tetrahydrofuran, dioxane, dichloroethane, cyclohexanone, toluene, methyl ethyl ketone, acetone, and dip coating, spray coating, bead coating, It can be formed by coating with a ring coat or the like. Further, if necessary, various additives such as the plasticizer, leveling agent, antioxidant and lubricant can be added. The film thickness of the photosensitive layer 33 is suitably about 5 to 25 μm.

In the present invention, a protective layer may be formed as the outermost surface layer on the charge transport layer, charge generation layer or photosensitive layer, which is more effective in the present invention.
The present invention can be used with any photoreceptor as long as the elastic displacement rate τe of the photoreceptor surface is 40% or more. Thereby, the stress due to mechanical rubbing of the photosensitive member abutting object can be relieved, and the durability of the effect of linear flaws is improved at the same time as the wear resistance is improved, which is effective and useful.
A higher elastic displacement rate τe is more effective in increasing wear resistance, but the value varies greatly depending on the material used. The elastic displacement rate τe in the present invention is preferably 40 to 90%. In the case of the acrylic cured film of the present invention, 40 to 60% is preferable. If the elastic displacement rate τe is less than this, it will cause a significant decrease in durability due to a decrease in wear resistance, an increase in uneven wear, etc. There is a risk of promoting. On the other hand, if the elastic displacement rate τe increases more than necessary, there is a risk that the effects of cleaning failure and filming will increase.

The elastic displacement rate τe of the present invention is measured by a load-unloading test of a micro surface hardness meter using, for example, a Vickers indenter. As shown in FIG. 6, the indenter is pushed at a constant load speed from the point (a) where the indenter contacts the sample (load process), and is stationary for a certain time at the maximum displacement (b) when the set load is reached. The indenter is pulled up at the unloading speed (unloading process), and the point at which no load is finally applied to the indenter is defined as the plastic displacement (c). At this time, the obtained indentation depth and load curve are recorded as shown in FIG. 7, and the elastic displacement rate τe is calculated from the maximum displacement (b) and plastic displacement (c) by the following equation.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100
Such elastic displacement rate measurement is performed under a constant humidity. In the present invention, the elastic displacement rate indicates a measured value of the above test performed under environmental conditions of a temperature of 22 ° C. and a relative humidity of 55%.

  In the present invention, a dynamic micro surface hardness tester DUH-201 (Shimadzu Corporation) or Fisherscope H100 (Fisher Instruments) is used, and the indenter is measured using a Belkovic indenter (115 °) or a Vickers indenter. It may be a value measured by any device having equivalent performance. In the measurement, a photoreceptor prepared by laminating at least a photosensitive layer and a protective layer on an aluminum cylinder was appropriately cut and used. Since the elastic displacement rate τe is affected by the spring characteristics of the substrate, a rigid metal plate, a slide glass, or the like is suitable as the substrate in addition to an aluminum cylinder. Furthermore, since the hardness and elasticity factors of the protective layer (for example, charge transport layer, charge generation layer, etc.) are also affected, the maximum displacement is reduced to 1/10 of the surface layer thickness so as to reduce these effects. The specified weight was adjusted. Producing only the protective layer alone on the substrate is not preferable because the lower layer components are mixed and the adhesiveness with the lower layer changes, and the surface layer of the photoreceptor cannot be accurately reproduced.

The protective layer of the present invention is more effective and useful if it has a dynamic hardness (DH) of 22 or more in a measurement using a 115 ° triangular pan indenter (Belkovic 115 indenter).
Dynamic hardness is not a method of Vickers hardness or Knoop hardness, but a method of measuring how much the indenter has entered the sample. Generally, dynamic hardness (DH) is defined by the following formula.
DH = α × P / D ²
P: Test load (mN)
D: Amount of penetration of the indenter into the sample (pushing depth) (μm)
α: Constant depending on indenter shape
α = 3.8854 115 ° triangular indenter, Vickers indenter
15.018 100 ° Triangular Indenter

  This dynamic hardness is the hardness obtained from the load and indentation depth in the process of indenting the indenter, and it can obtain the material strength characteristics in a state including not only plastic deformation of the sample but also elastic deformation, Suitable for the present invention. In the present invention, the dynamic hardness of the photoreceptor surface was measured using a dynamic micro surface hardness meter DUH-201 (manufactured by Shimadzu Corporation) under environmental conditions of a temperature of 22 ° C. and a relative humidity of 55%. The indenter used for this includes a triangular pan indenter (115 °) (Belkovic indenter), a triangular pan indenter (100 °), a Vickers indenter, a Knoop indenter, etc., which are used properly depending on the measurement purpose. A triangular pan indenter (115 °) was used.

  In order to satisfy these characteristics, it is most suitable to use a curable resin for the protective layer, and it can be used effectively in the present invention. Examples of the curable resin include a thermosetting resin, a photocurable resin, and an electron beam curable resin. Among them, the ultraviolet curable resin has a high hardness and is most effectively used in the present invention. For example, urethane resin, acrylic resin, methacrylic resin, epoxy resin, silicon resin and the like are preferably used. In particular, acrylic resin is most preferable in terms of wear resistance, electrostatic characteristics, coating film quality, and image quality of the photoreceptor.

  However, in order to satisfy the electrostatic characteristics of the photoreceptor, it is necessary to impart a charge transport function to the protective layer. If the charge transport function is not provided, the residual potential is increased and sensitivity is deteriorated, and the image quality stability of the photoreceptor is greatly reduced. In order to impart a charge transport function to the protective layer, it is possible to include a charge transport material, but in particular, when such a curable resin is used, the compatibility with the charge transport material is low. For this reason, the quality of the film is deteriorated, for example, the charge transport material is precipitated or becomes cloudy, and the abrasion resistance may be remarkably lowered in some cases.

  In the present invention, by curing a radically polymerizable monomer having no charge transporting structure and a radically polymerizable compound having a charge transporting structure, film properties, electrical characteristics such as residual potential and sensitivity, It is preferable because the wear resistance and the like can be dramatically improved.

  The radically polymerizable monomer having no charge transporting structure is preferably trifunctional or more, whereby a three-dimensional network structure is developed, and the hardness and elastic displacement rate tend to be increased by increasing the crosslinking density. It is possible to obtain a further effect for improving the wear resistance. On the other hand, as the radical polymerizable compound having a charge transporting structure, a bifunctional or higher functional compound can be used as long as the smoothness, electrostatic characteristics, or durability of the photoreceptor surface is not impaired. However, when a radically polymerizable compound having a bifunctional or higher charge transporting structure is contained, the crosslink density can be increased, and thus the elastic displacement rate τe shows a relatively large value. However, a large number of bulky hole transporting compounds are present. Since they are entangled by bonding, the surface layer is distorted and the curing reaction becomes non-uniform. For this reason, the recovery force against the external stress is locally reduced, and the standard deviation of the elastic displacement rate τe is increased. As a result, unevenness is locally generated, which may reduce the effect of the present invention. Therefore, it is preferable to use a radical polymerizable compound having a monofunctional charge transport structure rather than a radical polymerizable compound having a bifunctional or higher functional charge transport structure.

  The trifunctional or higher functional radical polymerizable monomer having no charge transporting property used in the present invention is a hole transporting structure such as triarylamine, hydrazone, pyrazoline, carbazole, such as condensed polycyclic quinone, diphenoquinone, cyano group. And a monomer having no electron transport structure such as an electron-withdrawing aromatic ring having a nitro group and having three or more radical polymerizable functional groups. The radical polymerizable functional group may be any group as long as it has a carbon-carbon double bond and is capable of radical polymerization. Examples of these radical polymerizable functional groups include 1-substituted ethylene functional groups and 1,1-substituted ethylene functional groups shown below.

(1) Examples of the 1-substituted ethylene functional group include functional groups represented by the following formulas.
CH ₂ = CH—X ₁ −...
(However, in the formula, X1 is an arylene group such as a phenylene group and a naphthylene group which may have a substituent, an alkenylene group which may have a substituent, a —CO— group, a —COO— group, —CON (R ₁₀ ) — group (R ₁₀ represents an alkyl group such as hydrogen, methyl group or ethyl group, an aralkyl group such as benzyl group, naphthylmethyl group or phenethyl group, or an aryl group such as phenyl group or naphthyl group. Or represents a —S— group.)
Specific examples of these substituents include a vinyl group, a styryl group, a 2-methyl-1,3-butadienyl group, a vinylcarbonyl group, an acryloyloxy group, an acryloylamide group, and a vinyl thioether group.

(2) Examples of the 1,1-substituted ethylene functional group include functional groups represented by the following formulas.
CH ₂ = C (Y) -X ₂ -... Formula 11
(In the formula, Y is an aryl group such as an alkyl group which may have a substituent, an aralkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group. Group, halogen atom, cyano group, nitro group, alkoxy group such as methoxy group or ethoxy group, -COOR ₁₁ group (R ₁₁ is a hydrogen atom, an alkyl such as an optionally substituted methyl group or ethyl group) Group, an aralkyl group such as benzyl and phenethyl group which may have a substituent, an aryl group such as phenyl group and naphthyl group which may have a substituent, or -CONR ₁₂ R ₁₃ (R ₁₂ and R ₁₃ is a hydrogen atom, which may have a substituent an alkyl group such as methyl group and ethyl group, which may have a substituent group benzyl group, naphthylmethyl group or an aralkyl group such as a phenethyl group, or, A phenyl group which may have a substituent, an aryl group such as phenyl or naphthyl, which may be the same or different from each other.) Further, X ₂ is identical substituents and single and X ₁ of the formula 10 Represents a bond or an alkylene group, provided that at least one of Y and X ₂ is an oxycarbonyl group, a cyano group, an alkenylene group, and an aromatic ring.)

  Specific examples of these substituents include an α-acryloyloxy chloride group, a methacryloyloxy group, an α-cyanoethylene group, an α-cyanoacryloyloxy group, an α-cyanophenylene group, and a methacryloylamino group.

In addition, examples of the substituent further substituted with the substituent for X and Y include, for example, a halogen atom, a nitro group, an alkyl group such as a cyano group, a methyl group, and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, Examples thereof include aryloxy groups such as phenoxy group, aryl groups such as phenyl group and naphthyl group, aralkyl groups such as benzyl group and phenethyl group.
Among these radical polymerizable functional groups, acryloyloxy group and methacryloyloxy group are particularly useful, and a compound having three or more acryloyloxy groups is, for example, a compound having three or more hydroxyl groups in the molecule and an acrylic group. It can be obtained by using an acid (salt), an acrylic acid halide, or an acrylic ester to cause an ester reaction or a transesterification reaction. A compound having three or more methacryloyloxy groups can be obtained in the same manner. Further, the radical polymerizable functional groups in the monomer having three or more radical polymerizable functional groups may be the same or different.

Specific examples of the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure include the following, but are not limited to these compounds.
That is, examples of the radical polymerizable monomer used in the present invention include trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, trimethylolpropane alkylene-modified triacrylate, trimethylolpropane ethyleneoxy modification (hereinafter referred to as EO modification). ) Triacrylate, trimethylolpropane propyleneoxy modified (hereinafter PO modified) triacrylate, trimethylolpropane caprolactone modified triacrylate, trimethylolpropane alkylene modified trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA), glycerol triacrylate Glycerol epichlorohydrin modified (hereinafter ECH modified) Acrylate, glycerol EO modified triacrylate, glycerol PO modified triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), dipentaerythritol caprolactone modified hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkylated di Pentaerythritol pentaacrylate, alkylated dipentaerythritol tetraacrylate, alkylated dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, phosphoric acid EO modified triacrylate, 2,2,5,5 , -Tetrahydroxymethylcyclopentanone tetraacrylate And the like, which can be used in combination either alone or in combination.

  The trifunctional or higher functional radical polymerizable monomer having no charge transporting structure used in the present invention is a ratio of molecular weight to the number of functional groups in the monomer in order to form a dense crosslink in the protective layer ( The molecular weight / number of functional groups) is preferably 250 or less. As a result, the elastic displacement rate and hardness of the surface layer are improved, and the wear resistance of the surface of the photosensitive member tends to be increased. Further, when this ratio is larger than 250, the protective layer is soft and wear resistance is somewhat lowered. Therefore, in the monomers exemplified above, monomers having a modifying group such as EO, PO, and caprolactone are extremely long modified. It is not preferable to use a group having a group alone. Further, the proportion of the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure used in the protective layer is 20 to 80% by weight, preferably 30 to 70% by weight, based on the total amount of the protective layer. If the monomer component is less than 20% by weight, the three-dimensional cross-linking density of the protective layer is small, and a drastic improvement in wear resistance cannot be achieved as compared with the case of using a conventional thermoplastic binder resin. On the other hand, if it exceeds 80% by weight, the content of the charge transporting compound is lowered, and the electrical characteristics are deteriorated. The electrical properties and abrasion resistance required differ depending on the process used, and the film thickness of the protective layer of the photoconductor varies accordingly. The range of is most preferable.

  The radical polymerizable compound having a monofunctional charge transporting structure used in the protective layer of the present invention is a hole transporting structure such as triarylamine, hydrazone, pyrazoline, carbazole, such as condensed polycyclic quinone, diphenoquinone, It refers to a compound having an electron transport structure such as an electron-withdrawing aromatic ring having a cyano group or a nitro group, and having one radical polymerizable functional group. Examples of the radical polymerizable functional group include those shown in the above radical polymerizable monomer, and acryloyloxy group and methacryloyloxy group are particularly useful. In addition, a triarylamine structure is highly effective as a charge transporting structure, and in particular, when a compound represented by the structure of the following general formula (1) or (2) is used, electrical characteristics such as sensitivity and residual potential are good. To last.

[Wherein R ₁ represents a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, an aryl group which may have a substituent, a cyano group, a nitro group, Group, alkoxy group, —COOR ₇ (R ₇ is a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent), halogen Carbonyl group or CONR ₈ R ₉ (R ₈ and R ₉ may have a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or a substituent. Represents a good aryl group, which may be the same or different, and Ar ₁ and Ar ₂ represent a substituted or unsubstituted arylene group, which may be the same or different. Ar ₃ and Ar ₄ represent a substituted or unsubstituted aryl group, and may be the same or different. X represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group. Z represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkylene ether divalent group, or an alkyleneoxycarbonyl divalent group. m and n represent an integer of 0 to 3. )

Specific examples of general formulas (1) and (2) are shown below.
In the general formulas (1) and (2), in the substituent of R ₁ , examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group, and examples of the aryl group include a phenyl group and a naphthyl group. The aralkyl group includes a benzyl group, a phenethyl group, and a naphthylmethyl group, and the alkoxy group includes a methoxy group, an ethoxy group, a propoxy group, and the like. These include a halogen atom, a nitro group, a cyano group, and a methyl group. Substituted with an alkyl group such as an ethyl group, an alkoxy group such as a methoxy group or an ethoxy group, an aryloxy group such as a phenoxy group, an aryl group such as a phenyl group or a naphthyl group, an aralkyl group such as a benzyl group or a phenethyl group, etc. May be.

Among the substituents for R ₁ , particularly preferred are a hydrogen atom and a methyl group.
Ar ₃ and Ar ₄ are substituted or unsubstituted aryl groups, and examples of the aryl group include fused polycyclic hydrocarbon groups, non-fused cyclic hydrocarbon groups, and heterocyclic groups.
The condensed polycyclic hydrocarbon group preferably has 18 or less carbon atoms forming a ring, for example, a pentanyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptaenyl group, a biphenylenyl group, an as-indacenyl group. , S-indacenyl group, fluorenyl group, acenaphthylenyl group, preadenyl group, acenaphthenyl group, phenalenyl group, phenanthryl group, anthryl group, fluoranthenyl group, acephenanthrenyl group, aceanthrylenyl group, triphenylyl group, pyrenyl group , A chrycenyl group, a naphthacenyl group, and the like.

  Examples of the non-condensed cyclic hydrocarbon group include monovalent groups of monocyclic hydrocarbon compounds such as benzene, diphenyl ether, polyethylene diphenyl ether, diphenyl thioether and diphenyl sulfone, or biphenyl, polyphenyl, diphenylalkane, diphenylalkene, diphenylalkyne, Monovalent groups of non-condensed polycyclic hydrocarbon compounds such as triphenylmethane, distyrylbenzene, 1,1-diphenylcycloalkane, polyphenylalkane, and polyphenylalkene, or ring assemblies such as 9,9-diphenylfluorene And monovalent groups of hydrocarbon compounds.

Examples of the heterocyclic group include monovalent groups such as carbazole, dibenzofuran, dibenzothiophene, oxadiazole, and thiadiazole.
The aryl group represented by Ar ₃ or Ar ₄ may have a substituent as shown below, for example.
(1) Halogen atom, cyano group, nitro group and the like.
(2) Alkyl groups, preferably C _{1 to} C _12, especially C _{1 to} C ₈ , more preferably C _{1 to} C ₄ linear or branched alkyl groups, and these alkyl groups further include a fluorine atom , a hydroxyl group, a cyano group, an alkoxy group of C ₁ -C _4, a phenyl group or a halogen atom, which may have a phenyl group substituted by an alkoxy group C ₁ -C ₄ alkyl or C ₁ -C ₄ Good. Specifically, methyl group, ethyl group, n-butyl group, i-propyl group, t-butyl group, s-butyl group, n-propyl group, trifluoromethyl group, 2-hydroxyethyl group, 2-ethoxyethyl Group, 2-cyanoethyl group, 2-methoxyethyl group, benzyl group, 4-chlorobenzyl group, 4-methylbenzyl group, 4-phenylbenzyl group and the like.

(3) An alkoxy group (—OR ₂ ), and R ₂ represents the alkyl group defined in (2). Specifically, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, s-butoxy group, i-butoxy group, 2-hydroxyethoxy group, benzyloxy group And a trifluoromethoxy group.
(4) An aryloxy group, and examples of the aryl group include a phenyl group and a naphthyl group. It may contain an alkoxy group having C ₁ -C _4, alkyl group, or a halogen atom C ₁ -C ₄ as a substituent. Specific examples include a phenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 4-methoxyphenoxy group, and a 4-methylphenoxy group.
(5) Alkyl mercapto group or aryl mercapto group, and specific examples include methylthio group, ethylthio group, phenylthio group, p-methylphenylthio group and the like.

（式中、Ｒ₃及びＲ₄は各々独立に水素原子、前記（２）で定義したアルキル基、またはアリール基を表わす。アリール基としては、例えばフェニル基、ビフェニル基又はナフチル基が挙げられ、これらはＣ₁〜Ｃ₄のアルコキシ基、Ｃ₁〜Ｃ₄のアルキル基またはハロゲン原子を置換基として含有してもよい。Ｒ₃及びＲ₄は共同で環を形成してもよい）
具体的には、アミノ基、ジエチルアミノ基、Ｎ−メチル−Ｎ−フェニルアミノ基、Ｎ，Ｎ−ジフェニルアミノ基、Ｎ，Ｎ−ジ（トリール）アミノ基、ジベンジルアミノ基、ピペリジノ基、モルホリノ基、ピロリジノ基等が挙げられる。 (6)

(Wherein R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group defined in (2) above, or an aryl group. Examples of the aryl group include a phenyl group, a biphenyl group, and a naphthyl group, these may form a ring C ₁ -C ₄ alkoxy groups, C ₁ -C a alkyl group or a halogen atom ₄ which may contain as substituents .R ₃ and R ₄ jointly)
Specifically, amino group, diethylamino group, N-methyl-N-phenylamino group, N, N-diphenylamino group, N, N-di (tolyl) amino group, dibenzylamino group, piperidino group, morpholino group And pyrrolidino group.

(7) An alkylenedioxy group or an alkylenedithio group such as a methylenedioxy group or a methylenedithio group.
(8) A substituted or unsubstituted styryl group, a substituted or unsubstituted β-phenylstyryl group, a diphenylaminophenyl group, a ditolylaminophenyl group, and the like.

The arylene group represented by Ar ₁ or Ar ₂ is a divalent group derived from the aryl group represented by Ar ₃ or Ar ₄ .
X represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkylene ether group, an oxygen atom, a sulfur atom, or a vinylene group.

The substituted or unsubstituted alkylene group is a C _{1 to} C ₁₂ , preferably C _{1 to} C ₈ , more preferably a C _{1 to} C ₄ linear or branched alkylene group, and these alkylene groups include a fluorine atom, a hydroxyl group, a cyano group, an alkoxy group of C ₁ -C _4, a phenyl group or a halogen atom, a phenyl group substituted with an alkyl group or a C ₁ -C ₄ alkoxy group C ₁ -C ₄ It may be. Specifically, methylene group, ethylene group, n-butylene group, i-propylene group, t-butylene group, s-butylene group, n-propylene group, trifluoromethylene group, 2-hydroxyethylene group, 2-ethoxyethylene Group, 2-cyanoethylene group, 2-methoxyethylene group, benzylidene group, phenylethylene group, 4-chlorophenylethylene group, 4-methylphenylethylene group, 4-biphenylethylene group and the like.

で表わされ、Ｒ₅は水素、アルキル基（前記（２）で定義されるアルキル基と同じ）、アリール基（前記Ａｒ₃、Ａｒ₄で表わされるアリール基と同じ）、ａは１または２、ｂは１〜３を表わす。 The substituted or unsubstituted cycloalkylene group is a C _{5 to} C ₇ cyclic alkylene group, and these cyclic alkylene groups include a fluorine atom, a hydroxyl group, a C _{1 to} C ₄ alkyl group, and a C _{1 to} C ₄ alkyl group. It may have an alkoxy group. Specific examples include a cyclohexylidene group, a cyclohexylene group, and a 3,3-dimethylcyclohexylidene group.
The substituted or unsubstituted alkylene ether group represents ethyleneoxy, propyleneoxy, ethylene glycol, propylene glycol, diethylene glycol, tetraethylene glycol, tripropylene glycol, alkylene ether group alkylene group is hydroxyl group, methyl group, ethyl group, etc. You may have the substituent of.
The vinylene group is

R ₅ is hydrogen, an alkyl group (same as the alkyl group defined in (2) above), an aryl group (same as the aryl group represented by Ar ₃ or Ar ₄ above), a is 1 or 2 , B represents 1-3.

  Z represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkylene ether divalent group, or an alkyleneoxycarbonyl divalent group. Examples of the substituted or unsubstituted alkylene group include the same alkylene groups as those described above for X. Examples of the substituted or unsubstituted alkylene ether divalent group include the alkylene ether divalent group of X. Examples of the alkyleneoxycarbonyl divalent group include a caprolactone-modified divalent group.

Further, the radical polymerizable compound having a monofunctional charge transport structure of the present invention is more preferably a compound having a structure of the following general formula (3).

を表わす。） (Wherein, o, p and q are each an integer of 0 or 1, Ra represents a hydrogen atom or a methyl group, Rb and Rc represent a substituent other than a hydrogen atom and an alkyl group having 1 to 6 carbon atoms, And s and t each represents an integer of 0 to 3. Za is a single bond, a methylene group, an ethylene group,

Represents. )

As the compound represented by the above general formula, a compound having a methyl group or an ethyl group as a substituent for Rb and Rc is particularly preferable.
The radically polymerizable compound having a monofunctional charge transport structure represented by the general formulas (1) and (2), particularly (3) used in the present invention is polymerized with the carbon-carbon double bond open on both sides. Therefore, in a polymer that is not a terminal structure but is incorporated in a chain polymer and crosslinked by polymerization with a tri- or higher functional radical polymerizable monomer, it exists in the main chain of the polymer, and Present in the cross-linked chain between the chain and the main chain (this cross-linked chain has an intermolecular cross-linked chain between one polymer and another polymer, and a site where the main chain is folded in one polymer. And other intramolecular cross-linked chains that are cross-linked with other sites derived from the polymerized monomer at positions away from this in the main chain), but even if they are present in the main chain, Even if present, the triarylamine structure suspended from the chain moiety is a nitrogen atom. It has at least three aryl groups arranged in the radial direction and is bulky, but is not directly bonded to the chain part, but is suspended from the chain part via a carbonyl group, etc. Since these triarylamine structures can be arranged adjacent to each other in the polymer, there is little structural distortion in the molecule, and the surface of the electrophotographic photosensitive member is also fixed. In the case of a layer, it is presumed that an intramolecular structure that is relatively free from interruption of the charge transport pathway can be adopted.

  Specific examples of the radically polymerizable compound having a monofunctional charge transporting structure of the present invention are shown below, but are not limited to the compounds having these structures.

  In addition, the radical polymerizable compound having a monofunctional charge transport structure used in the present invention is important for imparting the charge transport performance of the protective layer, and this component is preferably 20 to 80% by weight, preferably Is 30 to 70% by weight. If this component is less than 20% by weight, the charge transport performance of the protective layer cannot be maintained sufficiently, and repeated use causes deterioration of electrical characteristics such as a decrease in sensitivity and an increase in residual potential. On the other hand, if it exceeds 80% by weight, the content of the trifunctional monomer having no charge transport structure is lowered, and the crosslink density is lowered, so that high wear resistance is not exhibited. The electrical properties and abrasion resistance required differ depending on the process used, and the film thickness of the protective layer of the photoconductor varies accordingly. The range of is most preferable.

  The protective layer of the present invention is obtained by curing at least a trifunctional or higher-functional radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a monofunctional charge transport structure. Monofunctional and bifunctional radically polymerizable monomers and radically polymerizable oligomers can be used in combination for the purpose of imparting functions such as viscosity adjustment at the time, stress relaxation of the protective layer, low surface energy reduction and friction coefficient reduction. Known radical polymerizable monomers and oligomers can be used.

  Examples of the monofunctional radical monomer include 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethylhexyl carbitol acrylate, 3-methoxybutyl acrylate, benzyl acrylate, and cyclohexyl acrylate. , Isoamyl acrylate, isobutyl acrylate, methoxytriethylene glycol acrylate, phenoxytetraethylene glycol acrylate, cetyl acrylate, isostearyl acrylate, stearyl acrylate, styrene monomer, and the like.

Examples of the bifunctional radically polymerizable monomer include 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1, Examples include 6-hexanediol dimethacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, bisphenol A-EO modified diacrylate, bisphenol F-EO modified diacrylate, and neopentyl glycol diacrylate.
Examples of the functional monomer include those substituted with a fluorine atom such as octafluoropentyl acrylate, 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, 2-perfluoroisononylethyl acrylate, No. 60503, JP-B-6-45770, siloxane repeating units: 20-70 acryloyl polydimethylsiloxane ethyl, methacryloyl polydimethylsiloxane ethyl, acryloyl polydimethylsiloxane propyl, acryloyl polydimethylsiloxane butyl, diacryloyl polydimethylsiloxane Examples include vinyl monomers having a polysiloxane group such as diethyl, acrylates and methacrylates.

  Examples of the radical polymerizable oligomer include epoxy acrylate, urethane acrylate, and polyester acrylate oligomers. However, when a large amount of monofunctional and bifunctional radically polymerizable monomers and radically polymerizable oligomers are contained, the three-dimensional cross-linking density of the protective layer is substantially decreased, resulting in a decrease in wear resistance. For this reason, the content of these monomers and oligomers is limited to 50 parts by weight or less, preferably 30 parts by weight or less, with respect to 100 parts by weight of the tri- or higher functional radical polymerizable monomer.

  Further, the protective layer of the present invention is obtained by curing at least a trifunctional or higher-functional radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a monofunctional charge transport structure. In order to advance this curing reaction efficiently, a polymerization initiator may be included in the protective layer coating solution.

  Examples of the thermal polymerization initiator include 2,5-dimethylhexane-2,5-dihydroperoxide, dicumyl peroxide, benzoyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di ( Peroxybenzoyl) hexyne-3, di-t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, lauroyl peroxide, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) B) Peroxide-based initiators such as propane, azo-based compounds such as azobisisobutylnitrile, azobiscyclohexanecarbonitrile, methyl azobisisobutyrate, azobisisobutylamidine hydrochloride, 4,4′-azobis-4-cyanovaleric acid Initiators are mentioned.

Examples of the photopolymerization initiator include diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 4- (2-hydroxyethoxy) phenyl- (2 -Hydroxy-2-propyl) ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2- Acetophenone-based or ketal-based photopolymerization initiators such as methyl-2-morpholino (4-methylthiophenyl) propan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether Benzoin ether photopolymerization initiators such as benzoin isopropyl ether, benzophenone, 4-hydroxybenzophenone, methyl o-benzoylbenzoate, 2-benzoylnaphthalene, 4-benzoylbiphenyl, 4-benzoylphenyl ether, acrylated benzophenone, Benzophenone photopolymerization initiators such as 1,4-benzoylbenzene, thioxanthones such as 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone Examples of photopolymerization initiators and other photopolymerization initiators include ethyl anthraquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoic acid. Phenylethoxyphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,4-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, methylphenylglyoxyester, 9,10 -Phenanthrene, an acridine type compound, a triazine type compound, an imidazole type compound is mentioned. Moreover, what has a photopolymerization acceleration effect can also be used individually or in combination with the said photoinitiator. Examples thereof include triethanolamine, methyldiethanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino) ethyl benzoate, 4,4′-dimethylaminobenzophenone, and the like.
These polymerization initiators may be used alone or in combination of two or more. The content of the polymerization initiator is 0.5 to 40 parts by weight, preferably 1 to 20 parts by weight with respect to 100 parts by weight of the total content having radical polymerizability.

  Furthermore, the protective layer coating liquid of the present invention may contain various plasticizers (for stress relaxation and adhesion improvement purposes), leveling agents, antioxidants, low molecular charge transport materials having no radical reactivity, etc. as necessary. An agent can be contained. As these additives, known additives can be used, and as plasticizers, those used in general resins such as dibutyl phthalate and dioctyl phthalate can be used, and the amount used is the total solid content of the coating liquid. To 20% by weight or less, preferably 10% or less. As leveling agents, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, polymers or oligomers having a perfluoroalkyl group in the side chain can be used, and the amount used is based on the total solid content of the coating liquid. 3% by weight or less is appropriate. If these additions are increased more than necessary, the crosslinking density may be reduced to inhibit curing, precipitate on the surface, the coating film may become cloudy, or phase separation may occur and become soluble in organic solvents. Since there is a possibility that the abrasion resistance of the photosensitive member may be greatly affected, it is necessary to keep the required minimum amount.

  The protective layer of the present invention comprises a coating liquid containing at least a trifunctional or higher-functional radical polymerizable monomer having no charge transport structure and a radical polymerizable compound having a monofunctional charge transport structure, which will be described later. It is formed by applying and curing on the layer. When the radically polymerizable monomer is a liquid, such a coating liquid can be applied by dissolving other components in the liquid, but if necessary, it is diluted with a solvent and applied. Solvents used at this time include alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, tetrahydrofuran, dioxane and propyl ether. Ethers such as dichloromethane, halogens such as dichloromethane, dichloroethane, trichloroethane, and chlorobenzene, aromatics such as benzene, toluene, and xylene, and cellosolves such as methyl cellosolve, ethyl cellosolve, and cellosolve acetate. These solvents may be used alone or in combination of two or more.

  As for the dilution solvent of the coating solution, if a large amount of a solvent that easily dissolves the lower layer (photosensitive layer, charge transport layer or charge generation layer) is used, the composition of the lower layer resin binder, low molecular charge transport material, etc., becomes the surface layer. In addition to hindering the curing reaction, it becomes the same state as when a large amount of a non-curing material is previously contained in the coating liquid, resulting in uneven curing of the crosslinked surface. Conversely, when a solvent that does not dissolve the lower layer at all is used, the adhesion between the surface layer and the lower layer decreases, and crater-like repellency appears on the surface layer due to volume shrinkage during the curing reaction, increasing the surface roughness of the photoreceptor. Or a lower layer having a low elastic displacement rate is partially exposed. These measures include using a mixed solvent to control the solubility of the lower layer, reducing the amount of solvent contained in the coating surface layer by the liquid composition and coating method, and using a polymer charge transport material as the lower layer. For example, an intermediate layer with low solubility or an intermediate layer with good adhesiveness is provided between the lower layer and the crosslinked surface layer to suppress mixing of components.

  In addition, even when a solvent having a low evaporation rate is used, the remaining solvent may hinder the curing or increase the amount of the lower layer component to be mixed, resulting in uneven curing and a decrease in the curing density. For this reason, it tends to be soluble in organic solvents. In this respect, tetrahydrofuran, tetrahydrofuran / methanol mixed solvent, ethyl acetate, methyl ethyl ketone, ethyl cellosolve, etc. are useful, but are selected according to the coating method. Moreover, regarding the solid content concentration, if it is too low for the same reason, it tends to be soluble in an organic solvent. Conversely, the upper limit concentration is constrained by the limitations of film thickness and coating solution viscosity. Specifically, it is desirable to use in the range of 10 to 50% by weight. As the coating method of the protective layer, for the same reason, the solvent content at the time of coating film formation, a method of reducing the contact time with the solvent is preferable, specifically, the spray coating method, the amount of coating liquid was regulated. A ring coat method is preferred.

In this invention, after apply | coating such a protective layer coating liquid, energy is given from the outside and it hardens | cures and forms a protective layer, but there exist a heat | fever, light, and a radiation as external energy used at this time. The heat energy is applied by heating from the coating surface side or the support side using a gas such as air or nitrogen, steam, various heat media, infrared rays, or electromagnetic waves. The heating temperature is preferably 100 ° C. or more and 170 ° C. or less, and if it is less than 100 ° C., the reaction rate is slow and the curing reaction is not completely completed. When the temperature is higher than 170 ° C., the curing reaction proceeds non-uniformly, and large strains, a large number of unreacted residues, and reaction termination terminals are generated in the protective layer. In order to proceed the curing reaction uniformly, it is also effective to complete the reaction by heating at a relatively low temperature of less than 100 ° C. and then heating to 100 ° C. or more. As the energy of light, UV irradiation light sources such as high-pressure mercury lamps and metal halide lamps, which mainly have an emission wavelength in ultraviolet light, can be used, but a visible light source can also be selected according to the absorption wavelength of radically polymerizable substances and photopolymerization initiators. Is possible. Irradiation light amount is 50 mW / cm ² or more, preferably 1000 mW / cm ² or less, it takes time for the curing reaction is less than 50 mW / cm ^2. If it is higher than 1000 mW / cm ^2, the progress of the reaction becomes non-uniform, local flaws occur on the surface of the protective layer, and a large number of unreacted residues and reaction termination ends occur. In addition, internal stress increases due to rapid crosslinking, which causes cracks and film peeling. Examples of radiation energy include those using electron beams. Among these energies, those using heat and light energy are useful because of easy reaction rate control and simple apparatus.

  In the protective layer of the present invention, it is necessary to contain a bulky charge transporting structure in order to maintain electrostatic properties, and to increase the cross-linking density in order to increase the strength. In curing after coating such a protective layer, if a very high energy is applied from the outside and the reaction proceeds rapidly, the curing proceeds non-uniformly and the variation in the elastic displacement rate τe increases, and the effectiveness of the present invention May decrease. For this reason, the thing using the external energy of the heat | fever which can control reaction rate by heating conditions, the irradiation intensity | strength of light, and the amount of polymerization initiators, or light is preferable.

  In the case of thermosetting, the heating temperature is preferably 100 to 170 ° C. For example, when a blowing oven is used as a heating means and the heating temperature is set to 150 ° C, the heating time is 20 minutes to 3 hours. After completion of curing, the photosensitive member of the present invention is obtained by further heating at 100 to 150 ° C. for 10 to 30 minutes to reduce the residual solvent.

  The present invention is characterized in that, in a structure in which a charge generation layer, a charge transport layer, and a protective layer are sequentially laminated, when the outermost protective layer is insoluble in an organic solvent, dramatic wear resistance is achieved. Yes. As a method for testing the solubility in an organic solvent, a drop of an organic solvent having high solubility in a polymer substance, for example, tetrahydrofuran, dichloromethane or the like, is dropped on the surface layer of the photoreceptor, and the surface shape of the photoreceptor is dried after natural drying. It can be determined by observing the change with a stereomicroscope. Dissolving photoconductors have a phenomenon that the central part of the droplet becomes concave and the surroundings swell up, the charge transport material precipitates and becomes cloudy or cloudy due to crystallization, and the surface swells and then shrinks, causing wrinkles Changes such as phenomena are observed. In contrast, an insoluble photoconductor does not exhibit the above-described phenomenon, and does not change at all as before dropping.

  In the configuration of the present invention, in order to make the protective layer insoluble in the organic solvent, (1) the composition of the protective layer coating solution, adjustment of the content ratio thereof, (2) the diluted solvent of the protective layer coating solution, Controlling solid content concentration, (3) selection of coating method of protective layer, (4) control of curing condition of protective layer, (5) poor solubility of charge transport layer under layer, etc. can be controlled. Important, but not achieved by a single factor.

  An example of a method for making the protective layer insoluble in an organic solvent in the configuration of the present invention is, for example, an acrylate monomer having three acryloyloxy groups and a triarylamine compound having one acryloyloxy group as a coating liquid. When used, the ratio of use is 7: 3 to 3: 7, and a polymerization initiator is added in an amount of 3 to 20% by weight based on the total amount of these acrylate compounds, and a solvent is added to prepare a coating solution. . For example, in the case where the surface layer is formed by spray coating using a triarylamine donor as the charge transport material and polycarbonate as the binder resin in the charge transport layer that is the lower layer of the protective layer, the solvent of the coating solution As for, tetrahydrofuran, 2-butanone, ethyl acetate, etc. are preferable, and the usage-amount is 3 times amount-10 times amount with respect to the acrylate compound whole quantity.

Next, for example, the prepared coating solution is applied by spraying or the like on a photoreceptor in which an undercoat layer, a charge generation layer, and the charge transport layer are sequentially laminated on a support such as an aluminum cylinder. Thereafter, it is naturally dried or dried at a relatively low temperature for a short time (25 to 80 ° C., 1 to 10 minutes) and cured by UV irradiation or heating.
For UV irradiation, it uses a metal halide lamp, illuminance 50 mW / cm ² or more, preferably 1000 mW / cm ² or less, at this time the drum temperature is controlled so as not to exceed 50 ° C..

In the present invention, countless linear scratches that intersect the surface of the protective layer formed on the outermost surface of the photoreceptor are uniformly formed. 8, 9, and 10 show examples of the surface of the photoconductor of the present invention, and FIGS. 11 and 12 show examples of the surface of the photoconductor different from the present invention. FIG. 13 shows another example of the surface of the photoreceptor of the present invention, and FIG. 14 shows the width, crossing angle, and interval of the linear scratches in the present invention. FIGS. 15 and 16 show examples of cross-sectional views of the formed linear scratches. However, these are merely examples of the present invention, and the present invention is not limited to these.
In the present invention, the elastic displacement rate τe defined by the following equation of the surface of the electrophotographic photosensitive member is 40% or more, and innumerable linear scratches intersecting each other are uniformly formed on the surface of the electrophotographic photosensitive member. Any photoreceptor is included as long as it is.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100
As described above, an infinite number of linear scratches in at least two directions intersect to suppress image flow in any direction.

  The linear flaw in the present invention refers to a flaw that is linear and has a concave shape. A dent scar is ineffective and needs to be a linear scratch. The linear scratches formed on the surface of the photoreceptor may have any shape, and the direction of the linear scratches formed is not particularly limited. Even if the line-shaped scratches are regularly arranged, the direction may not be uniform and may be a random pattern. Further, the linear scratch is not necessarily a straight line, and the linear scratch may have a curved line or a wavy line as long as it has a certain directionality. In the present invention, it is necessary to suppress the image flow that the linear flaw intersects at least from two directions, but more than that, for example, by intersecting more than three directions or four directions, a charge diffusion region is obtained. Is more effective for suppressing image flow. On the other hand, when only one-direction linear scratches are formed, as described above, it is not possible to obtain an image flow suppression effect for writing in any direction, and in some cases an image is only in one specific direction. This is not preferable because the flow may be emphasized.

  In the present invention, as described above, it is effective if innumerable linear scratches intersecting each other are formed uniformly, but a higher effect can be obtained if the following linear scratch formation conditions are satisfied. Is particularly effective. One of the conditions for forming a linear scratch is the width of the linear scratch. The average width of the linear scratches is preferably 10 μm or less, and more preferably 6 μm or less. If the average value of the width of the linear scratches is more than that, the scratches themselves may become streak-like image defects, or foreign matter may enter the scratches and induce filming. On the other hand, there is no problem with the reduction of the width, but since the image blur suppression effect tends to be reduced, the effect is sufficiently exhibited when the average value of the width of the linear scratches is 0.5 μm or more.

  The second is the crossing angle of linear scratches. In the present invention, 80% or more of the crossing angle of the linear scratches is preferably 135 degrees or less, and more preferably 90 degrees or less. When the area where the crossing angle is greater than 135 degrees exceeds 20% of the whole, even if the line scratches cross, a bias is seen in a specific direction, and the above-described writing direction dependency of the image flow is likely to occur. The suppression effect may be reduced. The smaller the crossing angle, the better the image flow suppression effect. However, if there are many areas where the crossing angle is remarkably small, the surface roughness of the photoconductor increases and the resolution may be reduced. It is preferably 15 degrees or more. A method of obtaining the crossing angle as a ratio per unit area of the crossing angle of 135 degrees or less by magnifying and observing an arbitrary number of points on the surface of the photoreceptor using a laser microscope or the like is suitable.

  The third is the interval between linear flaws. When the interval between the linear scratches is widened, the area of the image flow increases, so that there is a possibility that the resolution is lowered or the image flow is generated in a part of the image. Therefore, it is preferable that the linear scratch is uniformly formed on the entire surface of the photoreceptor. In the present invention, the interval between the linear scratches is defined by taking the direction perpendicular to the surface movement direction of the photoconductor as a reference line, and from the intersection of the reference line and the linear scratch to the intersection of the linear scratch adjacent thereto and the reference line. The average value is preferably 100 μm or less, and more preferably 60 μm or less. When the interval between the linear scratches is more than this, there is a possibility that the image flow suppression effect is reduced as described above. As the interval between the linear scratches is narrower, it is more advantageous for suppressing the image flow. However, if it is too narrow, the surface roughness is remarkably increased and the resolution may be lowered.

  Fourth, the depth of the linear wound also affects. In the present invention, the depth of the linear scratch is preferably 0.5 μm or less as an average value. When the depth of the linear scratch is larger than that, it is preferable for suppressing the image flow, but foreign matter is likely to enter and be difficult to remove, and an abnormal image may be generated. Further, if the average value of the depth of scratches is less than 0.1 μm, the effect of suppressing image blur may not be sufficiently exerted, so 0.1 μm or more is preferable.

  Further, as described above, the linear scratches are formed on the surface of the photoreceptor uniformly at fine intervals, so that a high effect can be obtained. In this case, the linear scratch is effective even if it is short and linear and formed uniformly. If the length of one linear scratch is at least 5 mm or more, the effect can be obtained. If the linear scratches are uniformly formed on the surface of the photoreceptor and satisfy the above-mentioned interval between the linear scratches, an infinite number of lines are formed. However, the number of linear scratches is not particularly limited. In the present invention, as described above, it is effective if it is uniformly formed on the surface of the photoreceptor, and the effect is further enhanced if the distance between the linear scratches is satisfied.

  The means for forming linear scratches intersecting the surface of the photoreceptor is not particularly limited, and conventionally known roughening methods can be applied. It is also possible to form linear scratches on the protective layer of the produced photoreceptor, or to form linear scratches when the protective layer is laminated, for example, directly on the protective layer surface of the produced photoreceptor. Any method such as a method of abutting and rubbing an abrasive, a method of pressing a mold having irregularities on the surface of the protective layer of the photoconductor, a method of forming a linear scratch at the stage of applying the protective layer of the photoconductor Can be applied. For example, as shown in FIGS. 17, 18 and 19, while rotating the photosensitive member, a contact object for forming a linear scratch is brought into contact, and the contact object itself is also rotated or reciprocated. This makes it possible to form linear scratches in various directions. Further, as shown in FIG. 20, a method of pressing a mold for forming a linear scratch on the surface of the photoreceptor is also possible. For the formation of linear scratches, linear scratches are formed by the above-mentioned method after preparation of the photoconductor, but when a cured protective layer is formed on the surface of the photoconductor, the linear scratches are formed by the above-mentioned method before curing. A method of forming and then curing is also possible and effective. In addition, it is not always necessary to form linear scratches immediately after the production of the photoconductor, and it is possible to form linear scratches by the above method while the photoconductor is used in the image forming apparatus, and the effect persistence. Above is very effective. Examples of abrasives to be brought into contact with the surface of the protective layer of the photoreceptor include natural fibers (eg animal hair, cotton, hemp), chemical fibers (rayon, acetate, nylon, polypropylene, acrylic, polyester, Teflon (registered trademark), etc.) Glass fiber or stainless steel fiber, felt, cloth, etc., sandpaper, films, brushes, polishing stones, etc. Even materials can be used.

  In the present invention, in order to improve the environmental resistance, at least one layer such as a charge generation layer, a charge transport layer, an undercoat layer, a protective layer, an intermediate layer, etc., in particular for the purpose of preventing a decrease in sensitivity and an increase in residual potential. In addition, an antioxidant, a plasticizer, a lubricant, an ultraviolet absorber, a low molecular charge transport material, and a leveling agent can be added to each layer. Representative materials of these compounds are described below.

Examples of the antioxidant that can be added to each layer include, but are not limited to, the following.
(A) Phenol compound 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, n-octadecyl-3- (4′- Hydroxy-3 ', 5'-di-t-butylphenol), 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-ethyl-) 6-t-butylphenol), 4,4′-thiobis- (3-methyl-6-tert-butylphenol), 4,4′-butylidenebis- (3-methyl-6-tert-butylphenol), 1,1,3 -Tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxy Benzyl) benzene, Tet Kis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, bis [3,3′-bis (4′-hydroxy-3′-t-butyl) Phenyl) butyric acid] glycol ester, tocopherols and the like.

(B) Paraphenylenediamines N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylene Diamine, N, N′-di-isopropyl-p-phenylenediamine, N, N′-dimethyl-N, N′-di-t-butyl-p-phenylenediamine and the like.
(C) Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2 -(2-octadecenyl) -5-methylhydroquinone and the like.

(D) Organic sulfur compounds Dilauryl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, ditetradecyl-3,3′-thiodipropionate, and the like.
(E) Organic phosphorus compounds Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine and the like.

Examples of the plasticizer that can be added to each layer include, but are not limited to, the following.
(A) Phosphate ester plasticizer Triphenyl phosphate, tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, trichloroethyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, Triphenyl phosphate etc.

(B) Phthalate ester plasticizers Dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, di-n-octyl phthalate, phthalate Dinonyl acid, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, butyl benzyl phthalate, butyl lauryl phthalate, methyl oleyl phthalate, octyl decyl phthalate, dibutyl fumarate, dioctyl fumarate Such.

(C) Aromatic carboxylic acid ester plasticizers Trioctyl trimellitic acid, tri-n-octyl trimellitic acid, octyl oxybenzoate, and the like.
(D) Aliphatic dibasic ester plasticizer dibutyl adipate, di-n-hexyl adipate, di-2-ethylhexyl adipate, di-n-octyl adipate, adipic acid n-octyl-n-decyl , Diisodecyl adipate, dicapryl adipate, di-2-ethylhexyl azelate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di-2-ethylhexyl sebacate, di-2 sebacate -Ethoxyethyl, dioctyl succinate, diisodecyl succinate, dioctyl tetrahydrophthalate, di-n-octyl tetrahydrophthalate and the like.

(E) Fatty acid ester derivatives butyl oleate, glycerin monooleate, methyl acetylricinoleate, pentaerythritol ester, dipentaerythritol hexaester, triacetin, tributyrin and the like.
(F) Oxyacid ester plasticizers Methyl acetyl ricinoleate, butyl acetyl ricinoleate, butyl phthalyl butyl glycolate, tributyl acetyl citrate and the like.
(G) Epoxy plasticizer Epoxidized soybean oil, epoxidized linseed oil, epoxy butyl stearate, decyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, dioctyl epoxy hexahydrophthalate, didecyl epoxy hexahydrophthalate, etc. .

(H) Dihydric alcohol ester plasticizers such as diethylene glycol dibenzoate and triethylene glycol di-2-ethylbutyrate.
(I) Chlorinated plasticizer Chlorinated paraffin, chlorinated diphenyl, chlorinated fatty acid methyl, methoxychlorinated fatty acid methyl and the like.
(J) Polyester plasticizer Polypropylene adipate, polypropylene sebacate, polyester, acetylated polyester and the like.

(K) Sulfonic acid derivatives p-toluenesulfonamide, o-toluenesulfonamide, p-toluenesulfoneethylamide, o-toluenesulfoneethylamide, toluenesulfone-N-ethylamide, p-toluenesulfone-N-cyclohexylamide and the like.
(L) Citric acid derivatives Triethyl citrate, triethyl acetylcitrate, tributyl citrate, tributyl acetylcitrate, tri-2-ethylhexyl acetylcitrate, acetylcitrate-n-octyldecyl, and the like.
(M) Others Terphenyl, partially hydrogenated terphenyl, camphor, 2-nitrodiphenyl, dinonylnaphthalene, methyl abietate and the like.

Examples of the lubricating substance that can be added to each layer include, but are not limited to, the following.
(A) Hydrocarbon compound Liquid paraffin, paraffin wax, microwax, low-polymerized polyethylene and the like.
(B) Fatty acid compounds Lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid and the like.
(C) Fatty acid amide compounds Stearylamide, palmitylamide, oleinamide, methylenebisstearamide, ethylenebisstearamide and the like.

(D) Ester compounds Lower alcohol esters of fatty acids, polyhydric alcohol esters of fatty acids, fatty acid polyglycol esters, and the like.
(E) Alcohol compounds Cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol, polyglycerol and the like.
(F) Metal soap Lead stearate, cadmium stearate, barium stearate, calcium stearate, zinc stearate, magnesium stearate and the like.
(G) Natural wax Carnauba wax, candelilla wax, beeswax, whale wax, ibota wax, montan wax and the like.
(H) Others Silicone compounds, fluorine compounds, etc.

Examples of the ultraviolet absorber that can be added to each layer include, but are not limited to, the following.
(A) Benzophenone series 2-hydroxybenzophenone, 2,4-dihydroxybenzophenone, 2,2 ', 4-trihydroxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4- Such as methoxybenzophenone.
(B) Salsylates Phenyl salsylates, 2,4 di-t-butylphenyl 3,5-di-t-butyl 4-hydroxybenzoate, and the like.
(C) Benzotriazole series (2′-hydroxyphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy5′-methylphenyl) benzotriazole, (2′-hydroxy3) '-Tertiarybutyl 5'-methylphenyl) 5-chlorobenzotriazole and the like.

(D) Cyanoacrylate-based ethyl-2-cyano-3,3-diphenyl acrylate, methyl 2-carbomethoxy 3 (paramethoxy) acrylate, and the like.
(E) Quencher (metal complex)
Nickel (2,2′thiobis (4-t-octyl) phenolate) normal butylamine, nickel dibutyldithiocarbamate, nickel dibutyldithiocarbamate, cobalt dicyclohexyldithiophosphate and the like.
(F) HALS (hindered amine)
Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6 6-tetramethylpyridine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy- 2,2,6,6-tetramethylpiperidine and the like.

Next, the entire image forming apparatus of the present invention will be described in detail with reference to the drawings. In addition, the figure and description shown below are examples for demonstrating this invention, and are not limited to this.
FIG. 21 is a schematic diagram for explaining the image forming apparatus of the present invention. The photoreceptor 1 of the present invention is used as the photoreceptor 1. The photosensitive member 1 has a drum shape, but may be a sheet shape or an endless belt shape.
As the charging member, any of non-contact charging by a corotron, scorotron, a solid state charger (solid state charger) or the like, or contact charging by a charging roller or a charging brush can be used. Further, when a charging roller is used, it is possible to provide a gap in the photoconductor or the charging roller as shown in FIG. 22 and arrange the photoconductor and the charging roller close to each other so that they are not in contact with each other in the image forming area. Yes, it is effective. In particular, when lubricating substances are attached to the surface of the photoreceptor, they may be attached to the charging roller to promote contamination of the charging roller.

  Contamination of the charging roller may cause uneven charging or promote contamination of the photoreceptor. Therefore, since the charging roller and the photoconductor are arranged close to each other, an effect of suppressing them may be obtained, which is effective. As a method of placing the charging member close to the photosensitive member, it is necessary to provide a gap in the non-image forming region of the photosensitive member. For example, a gap material is provided on the charging member, on the photosensitive member side, or on the photosensitive member. In the present invention, any method can be used as long as the photosensitive member and the charging member are disposed close to each other.

  When the gap material is used in this way, the gap material needs to be insulative, and a material with high wear resistance is effectively used. The gap material can be used in any form such as tape, seal or tube. The thickness of the gap is preferably 10 to 200 μm, more preferably 20 to 100 μm, and further preferably 40 to 80 μm. If the gap is smaller than this, there will be more contact between the charging member and the photoconductor, and the merit of placing them closer will not be obtained, and the effect of image quality degradation will increase. If the gap is larger than this, charging will be stable. May deteriorate and charging unevenness may occur. Further, the charging member can be charged with a charge by superimposing an AC component on a DC component. By superimposing an alternating current component, it is possible to reduce charging unevenness, thereby suppressing image density unevenness and contrast deterioration, which is useful.

  In the corona charging method using corotron or scorotron, the amount of discharge products adhering to the surface of the photoreceptor tends to be relatively small, but the amount of ozone generated tends to be very large. On the other hand, when a charging roller is used, the amount of ozone generated can be reduced, but the amount of discharge product attached tends to increase. Although ozone and discharge products are factors that have a large effect on image flow, etc., since the present invention is a means for suppressing image flow due to adhesion of discharge products, the effect is obtained when a charging roller is used as the charging means. It will be demonstrated more.

  Next, the image exposure unit 5 is used to form an electrostatic latent image on the uniformly charged photoconductor. As the light source, all luminescent materials such as a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and an electroluminescence (EL) can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.

  Next, the developing unit 6 is used to visualize the electrostatic latent image formed on the photoreceptor. Examples of the development method include a one-component development method using a dry toner, a two-component development method, and a wet development method using a wet toner. When the 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. When this is developed with negative (positive) polarity toner (electrodetection fine particles), a positive image can be obtained, and when developed with positive (negative) polarity toner, a negative image can be obtained.

  The development unit in the full-color image forming apparatus has a unit corresponding to at least four colors of yellow, magenta, cyan, and black. Four color toners are separated and filled in the development unit, and the unit itself rotates in four stages to sequentially develop the four colors. For each of the four units filled with the four color toners, the revolver method Examples include a tandem system in which four photoconductors are arranged.

  Preparation of toner is generally performed by pulverization or polymerization, but in recent years, a polymerization method has been used. It is known that a toner having a spherical shape can be easily obtained by polymerization, but because the toner has a spherical or substantially spherical shape, the releasability is improved, so that the toner remaining on the photoreceptor during transfer is small, It is possible to improve transfer efficiency and suppress abnormal images such as voids. However, since spherical or substantially spherical toner significantly reduces the cleaning properties, conventionally, it has been necessary to avoid the spherical or substantially spherical shape, so that sufficient transfer efficiency has not been obtained. . In the present invention, by forming linear scratches intersecting the photoconductor, it is possible to give a further effect to the transfer efficiency by improving the releasability and to greatly improve the cleaning performance. When the linear scratches formed on the surface of the photoconductor are in one direction, especially when they are formed in the circumferential direction of the photoconductor, spherical or substantially spherical toner is easy to roll and greatly reduces the cleaning performance. However, in the present invention, the linear flaws are formed so as to intersect with each other, so that it is possible to suppress the movement of the toner, and the contact area between the cleaning blade and the photosensitive member is reduced. It was possible to improve the cleaning property by reducing excessive friction.

  Next, the toner image visualized on the photosensitive member is transferred onto paper or an intermediate transfer member. FIG. 23 is a schematic diagram for explaining an image forming apparatus having a configuration in which the intermediate transfer belt is in contact with the photosensitive member and the photosensitive member and paper are not in direct contact with each other in the present invention. The intermediate transfer member may be in the form of a drum, a sheet, or an endless belt. The toner image formed on the intermediate transfer member or the intermediate transfer belt is immediately transferred to paper. As these transfer means, conventional methods such as an electrostatic transfer method using a transfer charger and a bias roller, a mechanical transfer method such as an adhesive transfer method and a pressure transfer method, and a magnetic transfer method can be used.

  When the toner is transferred from the photoconductor, if the releasability of the photoconductor is low, the toner remains on the photoconductor, which may cause voids or image quality deterioration due to a decrease in transfer efficiency. In the present invention, since the effect of improving the releasability on the surface of the photoreceptor is also obtained, it has become possible to simultaneously improve the transfer efficiency and the suppression of voids. In addition, since the intermediate transfer belt is in contact with the photosensitive member and the photosensitive member and the paper are not in direct contact with each other, an effect of suppressing the adhesion of paper dust on the surface of the photosensitive member can be obtained. The adhesion of discharge products and toner external additives to the surface of the photoconductor attracts paper dust, which may promote filming. However, the photoconductor and paper are in direct contact using an intermediate transfer belt. By not having it, it is possible to greatly suppress the influence.

  FIG. 24 is a schematic view of an image forming apparatus that is a tandem type and includes an intermediate transfer belt. In the above tandem image forming apparatus, each toner image formed on each photoconductor is subjected to primary transfer onto an intermediate transfer body or an intermediate transfer belt, and then secondary transfer is performed on the transfer body (paper). As described above, the configuration in which the photoconductor and the paper are not in direct contact is very effective for high durability and high image quality. In particular, in a tandem type image forming apparatus, it is necessary to minimize deterioration with time between photoreceptors as much as possible, and not only the amount of wear on the photoreceptor surface but also the influence of contamination on the photoreceptor surface. When a large difference occurs between the two, a mechanism for forming one image by the four photoconductors causes image deterioration such as color reproducibility and resolution reduction.

  In particular, when a void occurs, the color reproducibility also decreases, and in the case of a color image, the influence of the image quality deterioration becomes very large. In the case of the tandem method, the influence of paper dust tends to be large among discharge products, toner external additives, and paper dust that are contaminants on the surface of the photoreceptor. This is because each photoconductor needs to be in contact with the paper until at least four colors have been transferred, and the amount of toner used differs depending on the type of color to be printed. Regardless, the photoreceptor must be in constant contact with the paper. For example, when printing only black, a mechanism that prevents the three photoconductors other than black from coming into contact with the paper is considered. It is common for the influence of to increase. Therefore, in the tandem image forming apparatus, when the toner image on the photosensitive member is primarily transferred to the intermediate transfer member or the intermediate transfer belt, the photosensitive member and the paper are not in direct contact with each other. By using this photoconductor, it becomes particularly effective not only for enhancing the durability of the photoconductor but also for suppressing image blurring and filming, improving color reproducibility and resolution, and the like.

  Next, a fur brush, a cleaning blade, or a combination thereof is used to clean the toner remaining on the photoconductor after transfer. In the present invention, only the toner remaining on the photoconductor surface is cleaned. In particular, since it is necessary to remove the discharge product adhering to the photosensitive member, a cleaning blade is preferably used as the cleaning means. By forming linear scratches intersecting the surface of the photoconductor, the contact area between the photoconductor and the cleaning blade can be reduced, thereby suppressing excessive friction and improving the cleaning performance. In addition, since the discharge products entered the linear scratches and the locations where the discharge products remained could be distinguished, the influence of image flow could be suppressed, and at the same time, the cleaning performance of the discharge products adhering to the photoreceptor surface was improved. As a result, the image quality can be improved and the stability thereof can be improved.

  In order to impart slipperiness, it is possible to attach a compound containing a slippery component to the surface of the photoreceptor. This is very effective for improving the releasability of the photosensitive member, increasing the wear resistance, and suppressing the adhesion of foreign matter. In particular, it is also effective for cleaning discharge products, and a synergistic effect can be obtained by combining with the photoreceptor of the present invention. As the compound imparting slipperiness contained in the protective layer, any material may be used as long as the slipperiness is imparted by addition, but in particular, a silicone compound, a fluorine compound, and a long chain alkyl group are contained. Compounds are used effectively. The silicone compound includes any compound that contains Si in the molecular structure, and examples thereof include silicone resins and resin fine particles. The fluorine-based compound includes any compound having F in its molecular structure, and examples thereof include various fluororesin fine particles such as PTFE, PFA, and PVDF.

  The long-chain alkyl group-containing compound includes any material that contains a long-chain alkyl group, and zinc stearate is particularly effective. In addition, polyolefin resin, silicon grease, fluorine grease, paraffin wax, fatty acid esters, graphite, molybdenum disulfide, and the like can be given. By attaching these slipperiness-imparting compounds to the surface of the photoconductor, the sustainability of the effect of imparting releasability to the photoconductor has been remarkably improved, but it is difficult to control the amount of adhesion, and excessive adhesion Then, filming was promoted, and abnormal images and knitting wear were caused. In the present invention, the formation of linear scratches intersecting with the surface of the photoconductor causes the compound containing these slipping components to enter the scratch, thereby maintaining the slidability effect imparted to the surface of the photoconductor. As a result, excessive adhesion to the surface of the photoreceptor is suppressed, and as a result, the amount of lubricant adhered can be controlled. As a result, contamination on the surface of the photoreceptor can be suppressed, and occurrence of abnormal images and knitting wear can be suppressed.

  As a means for attaching the compound containing these slipping components to the surface of the photoreceptor, any method can be used. Specifically, a method in which a solid substance of these compounds is brought into direct contact with the surface of the photoreceptor or a photoreceptor. And a method in which a brush is brought into contact with the developer and adhered through the brush, or a method in which these compounds are mixed and adhered to the developer.

  The linear scratch formed on the surface of the photoconductor in the present invention may be formed when the photoconductor is not used. However, since the influence of wear occurs with the use of the photoconductor, the linear scratch is formed even after use. Therefore, it is possible to achieve both the wear resistance and the stabilization of the image quality, and the life of the photoreceptor can be greatly improved. Therefore, it is preferable that the image forming apparatus includes means for forming a linear scratch on the surface of the photoreceptor.

  Any means can be used for the image forming apparatus including means for forming linear scratches intersecting the surface of the photoreceptor of the present invention, but the abrasive is pressed against the photoreceptor as the image forming apparatus is used. The rubbing means is particularly effective. As an example, as shown in FIGS. 17, 18, and 19, the polishing object is brought into contact with the photosensitive member to reciprocate in the axial direction of the photosensitive member, rotate the photosensitive member, or move them simultaneously. Thus, a linear flaw can be formed in any direction. In addition, the scratches on the photoreceptor mainly formed by the developer and the cleaning blade over the course of use of the photoreceptor are also included in the linear scratches of the present invention.

  However, since most of the scratches formed on the photoconductor are unidirectional scratches in the circumferential direction of the photoconductor, it is necessary to form new linear scratches in a direction intersecting with the scratches. As a result, it is possible to suppress the image flow for lines in any direction. In addition, linear flaws are formed by pressing and rubbing the above-mentioned abrasive against the photoconductor, but at the same time, the effect of removing filming material etc. adhering to the surface of the photoconductor is also exhibited, further improving the image quality stabilization Can be obtained. The photosensitive member is worn by pressing and rubbing the polished material, but since this operation does not need to be performed at all times, the influence on the wear resistance of the photosensitive member is small.

Next, a neutralizing unit is used for the purpose of removing the latent image on the photoreceptor as required. As the charge removal means, a charge removal lamp and a charge removal charger are used, and the exposure light source and the charge means can be used respectively.
In addition, conventionally known processes such as document reading, paper feeding, fixing, and paper ejection that are not close to the photosensitive member can be used.

  The above illustrated electrophotographic process is illustrative of an embodiment of the present invention, and of course other embodiments are possible. For example, the light irradiation process includes image exposure, pre-cleaning exposure, and static elimination exposure. In addition, a pre-transfer exposure, pre-exposure of image exposure, and other known light irradiation processes are provided to light the photosensitive member. Irradiation can also be performed.

  These image forming means may be fixedly incorporated in a copying apparatus, facsimile, or printer, but may be incorporated in those apparatuses in the form of a process cartridge and detachable. Good. FIG. 25 is a schematic diagram illustrating an example of a process cartridge for an image forming apparatus. In FIG. 25, 101 is a photosensitive drum, 102 is a charging device, 103 is exposure, 104 is a developing device, 105 is a transfer body, 106 is a transfer device, and 107 is a cleaning blade. The process cartridge for an image forming apparatus according to the present invention includes a photoconductor and a cleaning unit, and at least one of a charging unit, a developing unit, a transfer unit, and a charge eliminating unit is integrated into and removed from the image forming apparatus main body. This is a possible part. According to the present invention, there is provided an image forming apparatus in which the photosensitive member is built in a process cartridge having a configuration that is detachable from the image forming apparatus main body, and the process cartridge is built in a tandem type image forming apparatus. The image forming apparatus having a configuration in which the photoconductor built in the sheet does not directly contact with the paper in the transfer process, the image forming apparatus combining them, and their process cartridges are all included.

  Hereinafter, although an example is given and the present invention is explained, the present invention is not restricted by an example. All parts are parts by weight.

<Example 1>
2. By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following composition on a φ30 mm aluminum cylinder in order by dip coating. A 5 μm undercoat layer, a 0.2 μm charge generation layer, and a 19 μm charge transport layer were formed. A coating solution for protective layer having the following composition was spray-coated on this charge transport layer, a 5.0 μm protective layer was laminated, and then naturally dried for 30 minutes.
[Coating liquid for undercoat layer]
Alkyd resin 6 parts (Beckosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals, Inc.)
Melamine resin 4 parts (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals, Inc.)
Titanium oxide 40 parts Methyl ethyl ketone 50 parts

[Coating liquid for charge generation layer]
Bisazo pigment pigment of the following structural formula (I) 2.5 parts Polyvinyl butyral (XYHL, manufactured by UCC) 0.5 part Cyclohexanone 200 parts Methyl ethyl ketone 80 parts

[Coating liquid for charge transport layer]
Bisphenol Z polycarbonate 10 parts (Panlite TS-2050, manufactured by Teijin Chemicals)
Low molecular charge transport material (D-1) having the following structural formula (II) 7 parts Tetrahydrofuran 100 parts 1% silicone oil tetrahydrofuran solution 0.2 part (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

[Coating liquid for protective layer]
Trifunctional or higher-functional radical polymerizable monomer having no charge transporting structure 10 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, Nippon Kayaku)
Molecular weight: 296, number of functional groups: trifunctional, molecular weight / number of functional groups = 99
10 parts of a radically polymerizable compound having a monofunctional charge transporting structure (Exemplary Compound No. 54)
Photoinitiator 1 part 1-Hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran 100 parts

Thereafter, intersecting linear scratches as shown in FIG. 8 were formed using a wrapping film sheet (particle size: 15 μm, 3M). The linear scratch was formed by rotating the photosensitive member as shown in FIG. 17, bringing a jig around which the wrapping film was wound into contact with the photosensitive member, and reciprocating at a constant speed while rotating. Next, the metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, the coating film is cured, and further dried at 130 ° C. for 20 minutes. An electrophotographic photoreceptor 1 of the present invention was produced. The average width of the linear scratches is 3.5 μm, the interval between the linear scratches is about 50 μm on average, the crossing angle of the linear scratches is 80% or more and 120 degrees or less, and the depth of the linear scratches is about 0.3 μm. It was confirmed by laser microscope observation.

<Example 2>
A radically polymerizable compound having a monofunctional charge transporting structure is obtained by replacing the trifunctional or higher radical polymerizable monomer having no charge transporting structure contained in the protective layer coating solution of Example 1 with the following monomer. Exemplified Compound No. The electrophotographic photosensitive member 2 was produced in the same manner as in Example 1 except that the thickness of the protective layer was changed to 5.2 μm instead of 138 and 10 parts. The average width of the linear flaws is 2.5 μm, the interval between the linear flaws is about 30 μm on average, the crossing angle of the linear flaws is 80% or more and 110 degrees or less, and the depth of the linear flaws is about 0.1 mm. It was confirmed by laser microscope observation that the thickness was 2 μm.
Trifunctional or higher radical polymerizable monomer having no charge transporting structure 10 parts Ditrimethylolpropane tetraacrylate (SR-355, manufactured by Kayaku Sartomer)
Molecular weight: 466, number of functional groups: 4 functions, molecular weight / number of functional groups = 117

<Example 3>
The trifunctional or higher functional radical polymerizable monomer having no charge transporting structure contained in the protective layer coating liquid of Example 1 was replaced with the following monomer, and the photopolymerization initiator was replaced with 1 part of the following compound. An electrophotographic photosensitive member 3 was produced in the same manner as in Example 1 except for the above. The average width of the linear flaws is 6.0 μm, the interval between the linear flaws is about 50 μm on average, the crossing angle of the linear flaws is 80% or more and 100 degrees or less, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that it was 3 μm.
Trifunctional or more radical polymerizable monomer having no charge transport structure 10 parts Caprolactone-modified dipentaerythritol hexaacrylate (KAYARAD DPCA-60, manufactured by Nippon Kayaku Co., Ltd.)
Molecular weight: 1263, number of functional groups: 6 functions, molecular weight / number of functional groups = 211

<Example 4>
The radical polymerizable compound having a monofunctional charge transporting structure contained in the protective layer coating liquid of Example 1 was exemplified as Compound No. 1. The electrophotographic photosensitive member 4 was produced in the same manner as in Example 1 except that 127 parts and 10 parts were used. The average width of the linear flaws is 1.5 μm, the average interval between the linear flaws is about 10 μm, the crossing angle of the linear flaws is 80% or more and 130 degrees or less, and the depth of the linear flaws is about 0.1 mm. It was confirmed by laser microscope observation that the thickness was 2 μm.

<Example 5>
Except that the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure contained in the protective layer coating liquid of Example 1 is replaced with the following two mixed monomers, and the photopolymerization initiator is replaced with the following compound. Produced an electrophotographic photoreceptor 5 in the same manner as in Example 1. The average width of the linear flaws is 8.0 μm, the interval between the linear flaws is about 70 μm on average, the crossing angle of the linear flaws is 80% or more and 90 degrees or less, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that the thickness was 4 μm.
Trifunctional or higher functional radical polymerizable monomer having no charge transport structure 6 parts Pentaerythritol tetraacrylate (SR-295, manufactured by Kayaku Sartomer)
Molecular weight: 352, number of functional groups: 4 functions, molecular weight / number of functional groups = 88
Trifunctional or higher functional radical polymerizable monomer having no charge transport structure 4 parts Alkyl-modified dipentaerythritol triacrylate (KAYARAD D-330, manufactured by Nippon Kayaku)
Molecular weight: 584, number of functional groups: trifunctional, molecular weight / number of functional groups = 195
Photoinitiator 1 part 2,2-Dimethoxy-1,2-diphenylethane-1-one (Irgacure 651, manufactured by Ciba Specialty Chemicals)

テトラヒドロフラン １００部
１％シリコーンオイルのテトラヒドロフラン溶液 ０．３部
（ＫＦ５０−１００ＣＳ、信越化学工業製） <Example 6>
In Example 1, a liquid containing a polymer charge transport material (PD-1) having the following composition was used as the charge transport layer coating liquid, and applied to the charge generation layer and dried to form a 19 μm charge transport layer. did. Thereafter, an electrophotographic photoreceptor 6 was produced in the same manner as in Example 1 except that a liquid having the following composition was used as the protective layer coating liquid and the liquid was applied on the charge transport layer. The average width of the linear scratches is 4.0 μm, the interval between the linear scratches is about 40 μm on average, 80% or more of the crossing angle of the linear scratches is 100 degrees or less, and the depth of the linear scratches is about 0.00 mm. It was confirmed by laser microscope observation that the thickness was 2 μm.
[Coating liquid for charge transport layer]
Polymer charge transport material (PD-1) having the following structural formula: 15 parts

Tetrahydrofuran 100 parts 1% silicone oil tetrahydrofuran solution 0.3 parts (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.)

[Coating liquid for protective layer]
Trifunctional or higher functional radical polymerizable monomer having no charge transport structure 6 parts Dipentaerythritol hexaacrylate (KAYARAD DPHA, Nippon Kayaku)
Molecular weight: 536, number of functional groups: 5.5 functional, molecular weight / number of functional groups = 97
Trifunctional or higher functional radical polymerizable monomer having no charge transport structure 4 parts Alkyl-modified dipentaerythritol triacrylate (KAYARAD D-330, manufactured by Nippon Kayaku)
Molecular weight: 584, number of functional groups: trifunctional, molecular weight / number of functional groups = 195
10 parts of a radically polymerizable compound having a monofunctional charge transporting structure (Exemplary Compound No. 54)
Photoinitiator 1 part 1-Hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran 100 parts

<Example 7>
In Example 1, the protective layer was applied, dried, and then crossed linear flaws as shown in FIG. 9 were formed using sandpaper (# 1000). As shown in FIG. 18, the linear flaws were formed by bringing a jig around which sandpaper was wound into contact with the photosensitive member and reciprocating or rotating the photosensitive member. Next, the metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, the coating film is cured by light irradiation, and further dried at 130 ° C. for 20 minutes. In addition, an electrophotographic photoreceptor 7 of the present invention was produced. The average width of the linear flaws is 8.0 μm, the interval between the linear flaws is about 60 μm on average, the crossing angle of the linear flaws is 80% or more and 90 degrees or less, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that the thickness was 5 μm.

<Example 8>
In Example 1, after the protective layer was applied, it was immediately brought into contact with a mold having a fine convex shape as shown in FIG. 20, and the linear scratches having the shape shown in FIG. Formed. Next, a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ^2, irradiation time: to cure the coating film subjected to light irradiation, a further 20 minutes drying at 130 ° C. was added in 60 seconds conditions The electrophotographic photoreceptor 8 of the present invention was produced. The average width of the linear scratches is 10 μm, the average interval between the linear scratches is about 100 μm, the crossing angle of the linear scratches is 80% or more and 60 degrees or less, and the depth of the linear scratches is about 0.5 μm. It was confirmed by laser microscope observation.

<Example 9>
In Example 1, the protective layer was applied and dried, and then contacted with a rotating brush by the method shown in FIG. 19 to form intersecting linear scratches as shown in FIG. Next, a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ^2, irradiation time: to cure the coating film subjected to light irradiation, a further 20 minutes drying at 130 ° C. was added in 60 seconds conditions An electrophotographic photoreceptor 9 of the present invention was produced. The average width of the linear scratches is 2.5 μm, the interval between the linear scratches is about 20 μm on average, the crossing angle of the linear scratches is 80% or more and 60 degrees or less, and the depth of the linear scratches is about 0. It was confirmed by laser microscope observation that the thickness was 2 μm.

<Example 10>
In Example 1, after the protective layer was applied and dried, a fixed brush was brought into contact as shown in FIG. 18 to form intersecting linear scratches as shown in FIG. Next, a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ^2, irradiation time: to cure the coating film subjected to light irradiation, a further 20 minutes drying at 130 ° C. was added in 60 seconds conditions An electrophotographic photoreceptor 10 of the present invention was produced. The average width of the linear scratches is 3.0 μm, the interval between the linear scratches is about 50 μm on average, the crossing angle of the linear scratches is 80% or more and 90 degrees or less, and the depth of the linear scratches is about 0. It was confirmed by laser microscope observation that the thickness was 2 μm.

<Example 11>
In Example 1, the protective layer was applied and dried, and thereafter, intersecting linear scratches as shown in FIG. 9 were formed using a polishing grindstone. Next, the metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, the coating film is cured by light irradiation, and further dried at 130 ° C. for 20 minutes. In addition, the electrophotographic photoreceptor 11 of the present invention was produced. The average width of the linear scratches is 10 μm, the interval between the linear scratches is about 110 μm on average, the crossing angle of the linear scratches is 80% or more and 90 degrees or less, and the depth of the linear scratches is about 0.5 μm. It was confirmed by laser microscope observation.

<Example 12>
In Example 1, the protective layer was applied and dried, and thereafter, intersecting linear scratches as shown in FIG. 9 were formed using a polishing grindstone. Next, the metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, the coating film is cured by light irradiation, and further dried at 130 ° C. for 20 minutes. In addition, an electrophotographic photoreceptor 12 of the present invention was produced. The average width of the linear scratches is 10 μm, the interval between the linear scratches is about 250 μm on average, 80% or more of the crossing angle of the linear scratches is 90 degrees or less, and the depth of the linear scratches is about 0.5 μm. It was confirmed by laser microscope observation.

<Example 13>
In Example 1, the protective layer was applied and dried, and then crossed linear scratches as shown in FIG. 8 were formed using a polishing grindstone. Next, the metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, the coating film is cured by light irradiation, and further dried at 130 ° C. for 20 minutes. In addition, an electrophotographic photoreceptor 13 of the present invention was produced. The average width of the linear scratches is 20 μm, the average interval between the linear scratches is about 100 μm, the crossing angle of the linear scratches is 80% or more and 135 degrees or less, and the depth of the linear scratches is about 0.8 μm. It was confirmed by laser microscope observation.

<Example 14>
Instead of providing the charge transport layer of Example 1, the following protective layer coating solution was applied and cured in the same manner on the charge generation layer, a 15.0 μm protective layer was provided, and after drying, sandpaper (# 1000) Was used to form intersecting linear flaws as shown in FIG. Thereafter, a metal halide lamp: 160 W / cm, irradiation distance: 120 mm, irradiation intensity: 500 mW / cm ² , irradiation time: 60 seconds, light application was performed to cure the coating film, and further drying at 130 ° C. for 20 minutes, An electrophotographic photoreceptor 14 of the present invention was produced. The average width of the linear flaws is 5.0 μm, the interval between the linear flaws is about 100 μm on average, the crossing angle of the linear flaws is 50% or more of 135 degrees or more, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that the thickness was 4 μm.
[Coating liquid for protective layer]
Trifunctional or higher functional radical polymerizable monomer having no charge transport structure 6 parts Caprolactone-modified dipentaerythritol hexaacrylate (KAYARAD DPCA-60, manufactured by Nippon Kayaku Co., Ltd.)
Molecular weight: 1263, number of functional groups: 6 functions, molecular weight / number of functional groups = 211
Trifunctional or higher radical polymerizable monomer having no charge transporting structure 4 parts Pentaerythritol tetraacrylate (SR-295, manufactured by Kayaku Sartomer)
Molecular weight: 352, number of functional groups: 4 functions, molecular weight / number of functional groups = 88
10 parts of a radically polymerizable compound having a monofunctional charge transporting structure (Exemplary Compound No. 54)
Photoinitiator 2 parts 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran 60 parts Cyclohexanone 20 parts

<Comparative Example 1>
The electrophotographic photoreceptor 15 is the same as in Example 1 except that the trifunctional or higher functional radical polymerizable monomer having no charge transporting structure contained in the protective layer coating solution of Example 1 is replaced with the following monomer. Was made. The average width of the linear scratches is 4.0 μm, the interval between the linear scratches is about 60 μm on average, the crossing angle of the linear scratches is 80% or more and 110 degrees or less, and the depth of the linear scratches is about 0.00 mm. It was confirmed by laser microscope observation that it was 3 μm.
Trifunctional or more radical polymerizable monomer having no charge transport structure 10 parts Caprolactone-modified dipentaerythritol hexaacrylate (KAYARAD DPCA-120, manufactured by Nippon Kayaku Co., Ltd.)
Molecular weight: 1947, number of functional groups: 6 functions, molecular weight / number of functional groups = 325

<Comparative example 2>
The amount of trifunctional or higher functional radical polymerizable monomer having no charge transporting structure contained in the protective layer coating solution of Example 2 is 6 parts, and the amount of radical polymerizable compound having a monofunctional charge transporting structure is An electrophotographic photosensitive member 16 was produced in the same manner as in Example 2 except that 14 parts were used. The average width of the linear scratches is 3.0 μm, the interval between the linear scratches is about 70 μm on average, the crossing angle of the linear scratches is 80% or more and 100 degrees or less, and the depth of the linear scratches is about 0. It was confirmed by laser microscope observation that the thickness was 2 μm.

<Comparative Example 3>
An electrophotographic photosensitive member 17 was produced in the same manner as in Example 1, except that the protective layer coating solution of Example 1 was changed to the following composition. The average width of the linear flaws is 5.0 μm, the interval between the linear flaws is about 40 μm on average, 80% or more of the crossing angle of the linear flaws is 100 degrees or less, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that the thickness was 5 μm.
[Coating liquid for protective layer]
Trifunctional or higher-functional radical polymerizable monomer having no charge transporting structure 8 parts Trimethylolpropane triacrylate (KAYARAD TMPTA, Nippon Kayaku)
Molecular weight: 296, number of functional groups: trifunctional, molecular weight / number of functional groups = 99
Polymer part 2 parts Bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals)
10 parts of a radically polymerizable compound having a monofunctional charge transporting structure (Exemplary Compound No. 54)
Photoinitiator 1 part 1-Hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
Tetrahydrofuran 100 parts

<Comparative example 4>
In Example 1, the amount of the radical polymerizable compound having a monofunctional charge transporting structure without containing a trifunctional or higher functional radical polymerizable monomer having no charge transporting structure as the composition of the protective layer coating liquid An electrophotographic photosensitive member 18 was produced in the same manner as in Example 1 except that was changed to 20 parts. The average width of the linear flaws is 6.5 μm, the interval between the linear flaws is about 50 μm on average, the crossing angle of the linear flaws is 80% or more and 95 degrees or less, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that the thickness was 2 μm.

<Comparative Example 5>
The curing conditions in the protective layer of Example 1, Example 1 the irradiation intensity using the same light source and 40 mW / cm ^2, irradiation time: instead of 5 minutes conditions, except that a protective layer of 5.1μm Example In the same manner as in Example 1, an electrophotographic photoreceptor 19 was produced. The average width of the linear flaws is 2.0 μm, the interval between the linear flaws is about 40 μm on average, the crossing angle of the linear flaws is 80% or more and 120 degrees or less, and the depth of the linear flaws is about 0. It was confirmed by laser microscope observation that the thickness was 4 μm.

<Comparative Example 6>
An electrophotographic photosensitive member 20 was produced in the same manner as in Example 1 except that the protective layer of Example 1 was not provided and the thickness of the charge transport layer was 24 μm. The average width of the linear scratches is 7.0 μm, the interval between the linear scratches is about 90 μm on average, the crossing angle of the linear scratches is 80% or more and 60 degrees or less, and the depth of the linear scratches is about 0.00. It was confirmed by laser microscope observation that the thickness was 4 μm.

<Comparative Example 7>
In Example 1, an electrophotographic photosensitive member 21 was produced in the same manner as in Example 1 except that the protective layer coating solution was changed to the following composition. The average width of the linear flaws is 2.5 μm, the interval between the linear flaws is about 20 μm on average, the crossing angle of the linear flaws is 80% or less of 80% or more, and the depth of the linear flaws is about 0.00. It was confirmed by laser microscope observation that it was 3 μm.
Alumina (average primary particle size: 0.3 μm, manufactured by Sumitomo Chemical Co., Ltd.): 3.5 parts Unsaturated polycarboxylic acid polymer (acid value 180 mgKOH / g, nonvolatile content 50%
"BYK-P104" manufactured by BYK Chemie): 0.06 parts Bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals):
10 parts Charge transport material of the above structural formula (II): 7 parts Tetrahydrofuran: 500 parts Cyclohexanone: 220 parts

<Comparative Example 8>
In Example 1, an electrophotographic photosensitive member 22 was produced in the same manner as in Example 1 except that linear scratches formed in one direction were formed as shown in FIG. 11 without intersecting the linear scratches. The average width of the linear scratches is 5.0 μm, the interval between the linear scratches is about 30 μm on average, the linear scratches do not intersect, and the depth of the linear scratches is about 0.3 μm by laser microscope observation. confirmed.

<Comparative Example 9>
In Example 1, an electrophotographic photosensitive member 23 was produced in the same manner as in Example 1 except that linear scratches formed in one direction were formed as shown in FIG. 12 without intersecting the linear scratches. The average width of the linear scratches is 5.0 μm, the interval between the linear scratches is about 30 μm on average, the linear scratches do not intersect, and the depth of the linear scratches is about 0.3 μm by laser microscope observation. confirmed.
<Comparative Example 10>
In Example 1, an electrophotographic photosensitive member 24 was produced in the same manner as in Example 1 except that no linear scratch was formed.

<Comparative Example 11>
In Comparative Example 7, an electrophotographic photosensitive member 25 was produced in the same manner as Comparative Example 7 except that no linear scratch was formed.

The electrophotographic photosensitive members 1 to 25 of Examples 1 to 14 and Comparative Examples 1 to 11 manufactured as described above were cut into appropriate sizes, a dynamic micro surface hardness meter DUH-201 (manufactured by Shimadzu Corporation), and a triangular pan indenter. (115 °) was used to measure the displacement-weighting curve in a load-stationary-unloading cycle. At this time, the set load was determined so that the maximum displacement was 1/10 of the cross-linked surface layer, the load and the unloading speed were 0.0145 gf / sec, and the stationary time of the maximum displacement was 5 seconds. The elastic displacement rate τe was calculated from the measured maximum displacement and plastic displacement by the following formula. The elastic displacement rate τe was measured at any 10 locations on the sample, and the average was taken as the value, and the standard deviation of the elastic displacement rate was calculated from these 10 elastic change rates. The results are shown in Table 4.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100
This dynamic microhardness measurement was performed under environmental conditions of a temperature of 22 ° C. and a relative humidity of 55%. The dynamic hardness DH was measured using a dynamic micro surface hardness meter DUH-201 (manufactured by Shimadzu Corporation) and a triangular pan indenter (115 °). The results are also shown in Table 4.

The electrophotographic photosensitive members 1 to 25 of Examples 1 to 14 and Comparative Examples 1 to 11 produced as described above were mounted on a process cartridge for an image forming apparatus, and a semiconductor laser having a wavelength of 655 nm as an image exposure light source was used. Initial image output was performed with a modified digital copier manufactured by Ricoh Co., Ltd. equipped with a charging roller and a cleaning blade. Thereafter, 20,000 continuous paper-runs were performed in an environment of 30 ° C. and 90% RH, and the image was output as it was after the end of the run. Finally, the amount of wear was determined from the difference in film thickness before and after the paper passing run. The image rank was distinguished by the following symbols.
◎: Good image with no image flow recognized ○: Image flow is slightly recognized, but it can be judged that there is no problem in quality △: Image flow is clearly recognized, characters are difficult to read, and dot scattering is conspicuous
×: Level where the dots are completely scattered by the image flow and the characters cannot be read

From the results of Table 1, the electrophotographic photosensitive member of the present invention having an elastic displacement rate τe of 40% or more and forming linear scratches intersecting each other on the surface is very high in wear resistance. It was revealed that a good image can be maintained even in a running test under a high temperature and high humidity environment. On the other hand, the electrophotographic photosensitive member having an elastic displacement rate τe of less than 40% has reduced wear resistance. Since the discharge products were removed by the abrasion, no image flow occurred. However, the lifetime was reduced by the abrasion, and the occurrence of scumming was observed accordingly. Further, when the electrophotographic photosensitive member surface contains a filler, an improvement in wear resistance was realized, but the elastic displacement rate τe was less than 40%, and image defects due to adhesion of foreign matter were recognized. Further, when no linear scratch was formed, image flow was observed in addition to foreign matter adhesion, and the image quality further deteriorated.
In addition, when only the vertical direction was formed without intersecting the linear scratches, the resolution was reduced only in the vertical direction. Similarly, when only the horizontal direction is formed, the resolution is reduced only in the horizontal direction. Furthermore, even when the elastic displacement rate τe was 40% or more, a decrease in resolution was observed when no linear scratch was formed on the surface.

   Next, the surfaces of the electrophotographic photoreceptors 1 to 25 are wiped with a non-woven fabric containing ethanol, further wiped with a non-woven fabric containing water, repeated several times, and then dry-wiped to obtain the photoreceptor surface. The discharge product adhering to was removed. These images were output again using a Ricoh Co., Ltd. digital copier remodeling machine equipped with a charging roller and a cleaning blade using a semiconductor laser having an image exposure light source wavelength of 655 nm.

Subsequently, these electrophotographic photosensitive members are transferred to a process cartridge from which the developing unit and the cleaning unit have been removed, the transfer unit is also removed, and a free run with only charging and discharging is performed for 30 minutes in an environment of 30 ° C. and 90% RH. Carried out. The image was returned to a normal image forming process cartridge including a developing unit and a cleaning unit, and an image was output. The image rank was distinguished by the following symbols.
◎: Good image with no image flow ○: Image flow is recognized, but there is no problem in quality △: Image flow is clearly understood, characters are difficult to read, and dot scattering is conspicuous ×: Dots depending on image flow Is a level where characters are completely scattered and characters cannot be read

  In the results shown in Table 2, the effect of suppressing image blur was compared when the discharge product was forcibly adhered to the surface of the electrophotographic photosensitive member and accelerated deterioration occurred. The electrophotographic photosensitive member of the present invention having an elastic displacement rate τe of 40% or more and forming linear scratches intersecting each other on the surface is excellent under high temperature and high humidity even when a discharge product is forcibly adhered. It became clear that the image quality was maintained. As a result, high wear resistance and suppression of image flow due to adhesion of discharge products were realized. On the other hand, in the electrophotographic photosensitive member having an elastic displacement rate τe of less than 40%, the influence of uneven wear is large, and even if linear scratches intersecting with each other are formed, a cleaning failure occurs, and the discharge product cannot be completely removed. The occurrence of image blur was observed. In addition, although the electrophotographic photosensitive member containing a filler on the surface has improved wear resistance, the elastic displacement rate τe is less than 40%, and even if linear flaws are formed, cleaning is poor due to the effect of uneven wear. And the occurrence of image blur was observed. In this case, if the line flaws were not formed, the influence of the image flow was further increased, and even if the printing was repeated after the free run, the discharge product could not be completely removed, and the recoverability of the image flow was not recognized. Even if the elastic displacement rate τe is 40% or more, if no linear scratches crossing each other were formed, uneven wear was not observed, but the cleaning blade and the surface of the photoreceptor to which the discharge product was adhered The adhesive force increased, the blade turned up and could not be cleaned. In addition, when linear scratches are formed only in the vertical direction or only in the horizontal direction without intersecting each other, the resolution is improved compared to the case where no linear scratches are formed, but the image flow is sufficiently suppressed. I couldn't.

Next, zinc stearate was uniformly applied to the new electrophotographic photoreceptors 1 to 25 of Examples 1 to 14 and Comparative Examples 1 to 11. The coating method was carried out by bringing the solid material of zinc stearate and the photoconductor into contact with a rotating brush, and rotating the photoconductor to apply it to the photoconductor via the brush. These photoconductors are installed in a process cartridge for an image forming apparatus, a semiconductor laser having a wavelength of 655 nm as an image exposure light source is used, and a Ricoh tandem full-color printer remodeling machine equipped with a charging system and a cleaning blade shown in FIG. The images were output and the initial image evaluation was performed. As the toner, a substantially spherical toner having a particle diameter of about 6 μm was used. After that, 10,000 sheets were continuously run in an environment of 30 ° C. and 90% RH, and the image was output as it was after completion. The image rank was distinguished by the following symbols.
◎: Good image with no image defects ○: Level with no problem in image quality △: Image defect is confirmed but readable level ×: Image defect occurs frequently and unreadable

  From the results shown in Table 3, the electrophotographic photosensitive member of the present invention having an elastic displacement rate τe of 40% or more and forming linear scratches intersecting each other has good cleaning properties even when a substantially spherical toner is used. In addition, since the persistence of the coating effect of zinc stearate was high, good image quality was obtained. On the other hand, when the elastic displacement rate τe is less than 40%, the initial effect was good due to the coating effect of zinc stearate. There has occurred. In the photoreceptor containing the filler, the blade was missing due to the filler on the surface, and the soiling occurred due to poor cleaning. Moreover, some foreign matter adhesion was also recognized. In addition, when no linear scratch was formed, the effect of applying zinc stearate disappeared quickly, and when the substantially spherical toner slipped through the cleaning blade, poor cleaning occurred frequently and background contamination occurred.

It is the schematic which shows an example of the laminated constitution of the photoreceptor in this invention. It is the schematic which shows an example of the laminated constitution of the photoreceptor in this invention. It is the schematic which shows an example of the laminated constitution of the photoreceptor in this invention. It is the schematic which shows an example of the laminated constitution of the photoreceptor in this invention. It is the schematic which shows an example of the laminated constitution of the photoreceptor in this invention. It is explanatory drawing of the load-unloading test at the time of calculating | requiring elastic displacement rate (tau) e. It is explanatory drawing of elastic displacement rate (tau) e. It is the schematic which shows an example of the photoreceptor surface of this invention. It is the schematic which shows an example of the photoreceptor surface of this invention. It is the schematic which shows an example of the photoreceptor surface of this invention. It is the schematic which shows an example of the photoreceptor surface different from this invention. It is the schematic which shows an example of the photoreceptor surface different from this invention. It is the schematic which shows another example of the photoreceptor surface of this invention. It is the schematic which shows the crossing angle of the linear wound in this invention, a width | variety, and a space | interval. It is the schematic which shows an example of the cross-sectional shape of the linear damage | wound formed in the photoreceptor surface of this invention. It is the schematic which shows an example of the cross-sectional shape of the linear damage | wound formed in the photoreceptor surface of this invention. It is the figure which showed an example of the method of forming a linear flaw on the photoreceptor surface. It is the figure which showed an example of another method of forming a linear flaw on the photoreceptor surface. It is the figure which showed an example of another method of forming a linear flaw on the photoreceptor surface. It is the figure which showed an example of another method of forming a linear flaw on the photoreceptor surface. It is the figure which showed an example of the electrophotographic process by this invention. It is the schematic which showed an example of the charging method of this invention. It is the figure which showed another example of the electrophotographic process by this invention. It is the figure which showed an example of the electrophotographic process by this invention. It is the general figure which showed the process cartridge in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Static elimination lamp 3 Charging roller 4 Eraser 5 Image exposure part 6 Developing unit 7 Charger before transfer 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation charger 12 Separation claw 13 Cleaning charger 14 Cleaning brush belt 15 Cleaning blade 101 Photosensitive drum DESCRIPTION OF SYMBOLS 102 Charging device 103 Exposure 104 Developing device 105 Transfer body 106 Transfer device 107 Cleaning blade 108 Cleaning brush belt

Claims (22)

In an electrophotographic photosensitive member having at least a photosensitive layer on a conductive support , a protective layer is formed on the surface of the electrophotographic photosensitive member, and the protective layer is cured by heating or light energy irradiation. Insoluble to the surface, the elastic displacement rate τe defined by the following equation of the surface of the electrophotographic photosensitive member is 40% or more, and the surface of the electrophotographic photosensitive member has innumerable linear scratches intersecting each other. An electrophotographic photosensitive member, characterized in that the electrophotographic photosensitive member is formed.
Elastic displacement rate τe (%) = [(maximum displacement) − (plastic displacement)] / (maximum displacement) × 100 The electrophotographic photosensitive member according to claim 1, wherein an average value of the width of the linear scratches is 10 μm or less. 3. The electrophotographic photosensitive member according to claim 1, wherein 80% or more of the crossing angle of the linear scratches is 135 degrees or less. The linear shape defined as the distance from the intersection of the reference line and the linear scratch to the intersection of the linear scratch adjacent to the reference line and the reference line is a direction perpendicular to the surface movement direction of the electrophotographic photosensitive member spacing scratches, electrophotographic photosensitive member according to any one of claims 1 to 3, characterized in that an average value is 100μm or less. The electrophotographic photosensitive member according to the average value of the depth of the linear scratches, any one of claims 1 to 4, characterized in that at 0.5μm or less. Dynamic hardness of the surface of the electrophotographic photosensitive member (DH) is, in the measurement using the 115 ° triangular pyramid indenter (Berkovich 115 indenter), according to any one of claims 1 to 5, characterized in that at least 22 Electrophotographic photoreceptor. The protective layer is, according to any one of claims 1 to 6, characterized in that a layer formed by curing a radical polymerizable compound having a radical polymerizable monomer and a charge transport structure without at least a charge transport structure Electrophotographic photoreceptor. 8. The electrophotographic photosensitive member according to claim 7 , wherein the radical polymerizable monomer having no charge transporting structure is trifunctional or more, and the radical polymerizable compound having the charge transporting structure is monofunctional. . Ratio of molecular weight to functionality in the trifunctional or more radical polymerizable monomer not having charge transport structure (molecular weight / number of functional groups) is electrophotography according to claim 7 or 8, characterized in that 250 or less Photoconductor. The charged functional groups of the transport structure having no radically polymerizable monomer, an electrophotographic photosensitive member according to any one of claims 7 to 9, characterized in that the acryloyloxy groups and / or methacryloyloxy group. The electrophotographic photosensitive member according to any one of claims 7 to 10 , wherein the functional group of the radical polymerizable compound having a charge transporting structure is an acryloyloxy group and / or a methacryloyloxy group. The electrophotography according to any one of claims 1 to 11 , wherein at least one of a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound is contained on the surface of the electrophotographic photoreceptor. Photoconductor. The electron according to any one of claims 1 to 11 , wherein the protective layer has a functional group in a silicone compound, a fluorine compound, and a long-chain alkyl group-containing compound, and is cured by heating or light energy irradiation. Photoconductor. The image forming apparatus according to any one of claims 1 to 13 , wherein the electrophotographic photosensitive member is an image forming apparatus that forms an image by sequentially repeating at least charging, exposure, development, transfer, and cleaning steps on the electrophotographic photosensitive member. An image forming apparatus which is an electrophotographic photosensitive member. The image forming apparatus includes a plurality of electrophotographic photosensitive members corresponding to developing units that hold a plurality of toners having different colors, so that at least charging, exposure, development, and transfer processes are performed in parallel. The image forming apparatus according to claim 14 , wherein the image forming apparatus is of a type. 16. The image forming apparatus according to claim 14 , wherein the electrophotographic photosensitive member is charged by using a charging roller during the charging. In the image forming apparatus, an image forming apparatus according to any one of claims 14 to 16, wherein the use of spherical toner or substantially spherical during the development. In the image forming apparatus, an image forming apparatus according to any one of claims 14 to 17, characterized in that transferred to the paper through an intermediate transfer member and the intermediate transfer belt at the time of the transfer. In the image forming apparatus, an image forming apparatus according to any one of claims 14 to 18, characterized in that for cleaning using the cleaning blade during the cleaning. In the image forming apparatus, a silicone-based compound on the surface of the electrophotographic photosensitive member, fluorine-based compound, any one of claims 14 to 19, characterized in that it comprises means for attaching at least one long chain alkyl group-containing compound The image forming apparatus described in 1. In the image forming apparatus, an image forming apparatus according to any one of claims 14 to 20, characterized in that it includes a means for forming an infinite number of linear flaws which cross each other on the surface of the electrophotographic photosensitive member. 14. At least the electrophotographic photosensitive member is provided in a process cartridge for an image forming apparatus having a structure that is detachable from a main body of the image forming apparatus, and the electrophotographic photosensitive member is any one of claims 1 to 13 . An image forming apparatus process cartridge using an electrophotographic photosensitive member.

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