JP4898313B2 - Image forming method - Google Patents

Description

  The present invention relates to an image forming method in which a latent image is formed on an image carrier and the latent image is converted into a visible image (developer image) by a developing device. Used for forming equipment.

  The image formation by the electrophotographic method is to charge the surface of the electrophotographic photosensitive member and form an electrostatic latent image on the surface of the electrophotographic photosensitive member by irradiating the surface of the charged electrophotographic photosensitive member with exposure light. By developing the electrostatic latent image with toner, a toner image is formed on the surface of the electrophotographic photosensitive member, and the toner image is transferred from the surface of the electrophotographic photosensitive member to a transfer material such as paper to remove residual toner. In general, this is performed by a process of cleaning the surface of the electrophotographic photosensitive member. The surface of the electrophotographic photosensitive member is often charged using a charging member (such as a charging roller) disposed in contact with the surface of the electrophotographic photosensitive member. The surface is often cleaned using a cleaning member (such as a cleaning blade) disposed in contact with the surface of the electrophotographic photosensitive member.

  In recent years, in the market of copying machines and printers, multi-functions and high-functions have progressed, and accordingly, required images and performances have been diversified, and demands from the market have increased.

  In particular, in recent years, printers are often used simply as substitutes for copiers in offices, etc., and there is an increasing need for multi-function printers called multifunction printers equipped with functions such as scanners that can respond to various needs. ing. For these purposes, the required performance is not only low initial cost and low running cost, but also high-speed and large-scale printing, and image stability over a long period of time is required. In order to respond to changes in the environment, it is necessary to cope with downsizing and space saving.

  In order to meet the demands of the multi-function printer market, an organic photoreceptor that is relatively inexpensive and can be further reduced in diameter is generally used as a device for the main body. Further, in contrast to the downsizing of the main unit, the one-component developing method does not require carrier particles such as glass beads or iron powder as in the two-component method, so that the developing device itself can be reduced in size and weight. Furthermore, since the two-component development method needs to keep the toner concentration in the carrier constant, a device for detecting the toner concentration and supplying a necessary amount of toner is required. Therefore, the developing device is also large and heavy here. Since such a device is not necessary in the one-component development method, it is preferable because it can be made small and light.

  As described above, the printer market in recent years has been studied from both the main body and the toner in order to reduce the cost and the size. In particular, for the electrophotographic photosensitive member, the electrophotographic process applied thereto is used. It is required to have appropriate sensitivity, electrical characteristics, and optical characteristics. In addition, electrical and / or mechanical external force such as charging, exposure (image exposure), development with toner, transfer to paper or intermediate transfer member, cleaning of residual toner, etc. is directly applied to the surface of the electrophotographic photosensitive member. Therefore, the electrophotographic photosensitive member is also required to have durability against these external forces. Specifically, durability against the occurrence of scratches and wear on the surface due to rubbing, durability against surface deterioration due to charging (for example, a decrease in transfer efficiency and slipperiness), and electrical characteristics such as sensitivity reduction and potential reduction. Durability against deterioration is required.

  However, in recent years, in order to cope with higher speeds, high-strength, high-abrasion photosensitive drums with high wear resistance have come to be used, and it has become difficult to maintain the surface properties by scraping the photosensitive drum surface. Long-term accumulation of electrical damage due to electrification, surface deterioration due to adhesion of discharge products, mechanical damage due to rubbing with a cleaning blade, etc., resulting in slipperiness of the photosensitive drum surface (particularly against cleaning blades) As a result, the cleaning blade is liable to chatter, squeal, or squeak. Furthermore, since the surface of the photoconductor cannot be scraped, the discharge product is not removed, and when continuous and long-term printing is performed, contamination of the charging member proceeds, making it difficult to maintain a stable image. Occurred.

  Therefore, various methods have been considered so far to solve this problem.

  As one of attempts to increase the wear resistance of the organic photoreceptor, Patent Document 1 proposes to provide a high-hardness protective layer on the outermost surface layer of the photoreceptor. According to this, although the wear resistance is improved by the protective layer on the surface of the photoconductor, in addition to the high durability required for the multifunction printer such as the present invention, the size is reduced (the photoconductor is reduced in diameter). As the diameter of the cleaning blade decreases, it is difficult to follow the curvature of the photosensitive member, and it is difficult to maintain the optimum blade setting throughout the durability, and there is still room for improvement in terms of long-term cleaning performance.

  Further, in Patent Document 2, regarding the cleaning, an organic photoreceptor provided with a protective layer and an inorganic fine powder of a perovskite crystal are added to the toner particles as an abrasive so that the surface of the photoreceptor having the protective layer is positively applied. A method has been proposed in which the surface of the photoreceptor is refreshed by shaving to prevent image defects due to discharge products. However, when it is installed in a simple cartridge aiming at low cost, space saving, and miniaturization as in the present invention, when mass continuous printing like a copying machine is performed, the wear resistance of other members due to the accumulation of inorganic fine particles It is slightly disadvantageous for sex and there is room for improvement.

  Further, in Patent Document 3, in order to improve the cleaning property and transfer efficiency, the toner has a relatively spherical outline shape with a circularity of 0.95 or more and a shape factor SF-2 of 120 to 150. In addition, by using toner particles whose surface condition is uneven, the adhesive force is appropriate at the contact point with the latent image carrier, and the toner obtains good releasability from the latent image carrier, resulting in a high transfer rate. In addition, toner rolling on the latent image carrier can be suppressed, and proper contact between toner particles can be obtained, thereby preventing transfer dust and improving cleaning properties. There is a report.

  Further, as an attempt to improve long-term cleaning properties by suppressing the wear of the photoreceptor, for example, in Patent Document 4 and Patent Document 5, the toner and the toner are incorporated by adding fine aluminum nitride powder or fluorine-containing cerium oxide fine particles to the toner. It has been reported that the electrostatic force of the toner and the function as a lubricant for the cleaning blade and the photosensitive member are given to improve the cleaning property.

  However, in both cases, the remaining toner on the surface of the photoconductor and discharge products are completely removed at the contact portion of the cleaning blade, while maintaining the durability of the cleaning blade, which is a member that contacts the photoconductor. However, there is still room for improvement in terms of obtaining image stability and cleaning stability during long-term durability.

  Also, Patent Documents 6 and 7 propose attempts to control the friction between the photosensitive member and the cleaning blade as a conventional technique aimed at stabilizing cleaning from another viewpoint.

  Patent Document 6 describes a configuration in which a fluorine rubber or a silicone compound is contained in a urethane rubber cleaning blade so that the dynamic friction coefficient between the image carrier (photoconductor) and the cleaning blade is in the range of 0.2 to 1.2. Has been. Patent Document 7 describes a configuration in which fluororesin particles are contained in the outermost layer of the photoconductor and the coefficient of friction between the photoconductor surface and the urethane blade is less than 1.0 in order to improve the cleaning performance of the spherical toner. Has been.

  However, since the range of usable friction coefficients is as narrow as about 1.0 when controlled by these systems, it is difficult to fit the photoconductor and the cleaning blade to bring the friction coefficient into this range, which increases the cost. There is a problem that the cleaning performance tends to be unstable.

  Regarding the abrasion of the photosensitive member by the cleaning blade, Patent Document 8 and Patent Document 9 propose an example in which an inorganic photosensitive member is used as a photosensitive member instead of an organic photosensitive member to improve the wear resistance. The amorphous silicon photoconductors used in these are excellent in wear resistance, but the surface is not refreshed, the surface is not refreshed, and the slipping from the cleaning blade tends to increase. However, there is still room for improvement in order to have both downsizing, cost, and wear resistance, because it is difficult to reduce the size of the device in terms of manufacturing technology. is there.

  Further, Patent Documents 10, 11, and 12 disclose techniques that can achieve long-term image stability and transferability by utilizing the spacer effect of inorganic particles (silica particles) added to a toner. However, in addition to low initial cost and low running cost, such as a multi-function printer equipped with functions such as a scanner that can respond to various needs, when printing a large amount at a high speed, it is compatible with miniaturization and space saving, long-term There is still room for improvement in order to have all the stability of the image and the cleaning stability.

  In this way, in an electrophotographic development system using a simple cartridge such as that used in a small multifunction printer, the durability of the photoconductor and the cleaning blade can be maintained at the same time even in durable use such as a copying machine. Therefore, there is a demand for an image forming method capable of maintaining the image stability and the cleaning stability of the apparatus, and simultaneously reducing the size of the apparatus.

JP 2005-316262 A JP 2005-316225 A JP 2005-257976 A Japanese Patent Application Laid-Open No. 08-082948 Japanese Patent Application Laid-Open No. 08-082949 JP-A-4-335387 Japanese Patent Laid-Open No. 11-218953 JP-A-2005-227773 JP-A-11-249523 JP-A-5-142849 JP 2002-108001 A JP 2003-322998 A

  The object of the present invention has excellent cleaning properties and image stability in a small high-speed development system, and also has stable cleaning properties and high durability of an electrostatic charge carrier even when continuous printing is performed in large quantities. An object of the present invention is to provide an image forming method and developer excellent in preventing charging member contamination.

The present invention includes at least a step of charging an electrostatic charge image carrier by a charging member, an electrostatic latent image forming step of forming an electrostatic latent image on the charged electrostatic charge carrier, and a toner carrier to carry the electrostatic latent image carrier. A developing process for transferring the transferred toner to the electrostatic latent image for visualization, a transfer process for transferring the toner image formed on the electrostatic image bearing member onto the recording medium, and heat fixing the toner image to the recording medium In an image forming method comprising: a fixing step to perform; and a cleaning step of cleaning the surface of the electrostatic charge image carrier after transfer with a cleaning member;
The electrostatic image bearing member is a photosensitive member having a photosensitive layer and a protective layer on a support, and has a universal hardness value HU of 150 to 240 (N / mm ² ) on the surface of the photosensitive member, and an elastic property. The deformation ratio is 44% or more and 65% or less, and the cleaning member is a cleaning blade installed in contact with the electrostatic latent image bearing member,
The toner is a negatively chargeable magnetic toner having negatively chargeable magnetic toner particles containing at least a binder resin and magnetic iron oxide, and at least silica fine powder, and the silica fine powder has a volume-based median diameter (D50). 1/2 There is 0.70～3.00Myuemu, Ri silica fine powder der a specific surface area of 1.0~10.0m ² / g, further volume median diameter of powder the silica fine powder (D50) The volume distribution integrated value of double or less is 0.5 to 20.0%, and the volume distribution integrated value of double diameter or more is 0.5 to 20.0% .

  To provide an image forming method that has excellent cleaning properties and image stability in a small high-speed development system, and also has excellent cleaning properties, particularly prevention of charging member contamination even when a large amount of continuous printing is performed. I can do it.

  In fields where development with a view to long-term continuous use as an alternative to copiers, in addition to printer functions, such as multi-function printers, is relatively small by using simple configurations such as cartridges. In many cases, a laser beam printer is used which is advantageous in terms of cost reduction and image stability and speedup.

  In order to construct a high-speed and high-endurance development system in such a low-cost and simple system, cleaning stability over a long period of use of a high-endurance photoreceptor and a simple and relatively inexpensive cleaning blade is indispensable. .

The inventors of the present invention have made a study on a system for forming toner and an image, charging the electrostatic charge image carrier with a charging member, and forming an electrostatic latent image on the charged electrostatic charge carrier. A latent image forming step, a developing step of transferring the toner carried on the toner carrying member to the electrostatic latent image for visualization, and transferring the toner image formed on the electrostatic image carrying member onto a recording medium In the image forming method, the electrostatic charge image carrier comprises: a transferring step for fixing, a fixing step for heating and fixing the toner image on a recording medium; and a cleaning step for cleaning the surface of the electrostatic charge image carrier after the transfer with a cleaning member. A photosensitive member having a photosensitive layer and a protective layer on a support, the surface of the photosensitive member having a universal hardness value HU of 150 to 240 (N / mm ² ), and an elastic deformation ratio of 44% to 65 % Or more , And the said cleaning member is a cleaning blade disposed in contact with the electrostatic latent image bearing member,
The toner is a negatively chargeable magnetic toner having negatively chargeable magnetic toner particles containing at least a binder resin and magnetic iron oxide, and at least silica fine powder, and the silica fine powder has a volume-based median diameter (D50). Is excellent even in a small high-speed development system by using an image forming method characterized in that the specific surface area is from 1.00 to 3.00 μm and the specific surface area is from 1.0 to 10.0 m ² / g, It has been found that it has image stability, prevents deterioration of the surface of the photoreceptor even when a large amount of continuous printing is performed, and is excellent in preventing charging member contamination.

  That is, the inventors of the present invention use a photosensitive member having a specific hardness and elastic deformation rate and an image forming system that uses a cleaning blade as a cleaning member for removing residual toner, and the toner contains a binder resin and magnetic iron oxide. In addition, by incorporating a silica fine powder having at least a specific particle size and specific surface area, the abrasion resistance of the photosensitive member, the deterioration resistance of the cleaning blade, and the deterioration resistance of the toner itself are synergistically improved. It has been found that even when the apparatus is downsized, it has excellent cleaning properties, durability of image durability, and contamination resistance of the charging member.

  Hereinafter, the image forming method of the present invention will be described using the cartridge of FIG. 1 as one embodiment, but the present invention is not limited to this embodiment.

  As shown in FIG. 1, in general, a cartridge includes a photosensitive drum 13 that is an electrophotographic photosensitive member, a charging roller 2 as a charging unit for uniformly charging the photosensitive drum 13, a developing device 8, A cleaning blade 3 that is a cleaning unit that cleans the surface of the photosensitive drum 13 and a waste toner container 7 that stores residual toner removed from the photosensitive drum 13 by the cleaning blade 3 are integrally configured to form an electrophotographic image. It is detachably attached to a forming apparatus main body (hereinafter simply referred to as “apparatus main body”). The developing device 8 includes a toner container 6 that is a developer storage unit that stores toner T that is a developer, a developing container 9 that is connected to the toner container 6, and a developing roller as a developing unit that is disposed to face the photosensitive drum 13. 1. A developing blade 4 that is in contact with the developing roller 1 and controls the toner layer thickness, and the toner T in the toner container for stirring the toner T in the toner container 6 and feeding the toner T into the developing container 10. A stirrer member 11 is provided for conveying the toner T fed from the toner container to the developing roller 1. Further, a toner sealing member 12 is adhered between the toner container 6 and the developing container 9 before the cartridge is used. The toner sealing member 12 is provided so that the toner does not leak even when a severe impact occurs during transportation of the cartridge or the like, and is opened by the user immediately before mounting the cartridge in the apparatus main body. Further, the cartridge of FIG. 1 is an example of a cartridge having a plate antenna (PA) residual test and a storage device 5.

  In the residual inspection of the plate antenna (PA), a conductive plate PA is installed on the developing sleeve 1 via the toner T so as to form a capacitor structure in the toner container, and the developing sleeve 1 and the conductive plate PA are used for toner. Is configured to store.

  The storage device uses the image forming process setting values such as the charging bias setting value, development bias setting value, light amount setting value of the laser that is the exposure means, the usage amount of the photoconductor and the remaining amount of toner necessary for image formation. I remember the amount. In particular, a result of detecting the remaining amount of toner, which is information on the remaining printable number of cartridges, is stored, and information such as the number of usable cartridges is presented to the user, and optimal image formation according to the use history is performed. It is used as an indicator.

  In the above-described configuration, the photosensitive drum is uniformly charged by the charging roller, and the surface thereof is scanned and exposed by the laser light emitted from the laser scanner, thereby forming an electrostatic latent image of target image information. The electrostatic latent image is visualized as a toner image with toner attached thereto by the action of a developing roller or the like.

  When aiming at long-term stability, downsizing, and cost reduction of the image as in the present invention, the toner transferability is stabilized over a long period of time, and the durability of the small-diameter photosensitive member and the charge disturbing substance such as transfer residual toner Therefore, it is necessary to have cleaning stability that does not leave the toner on the photoreceptor.

  With regard to photoconductor cleaning properties, a cleaning blade that is relatively inexpensive in terms of material cost and excellent in mechanical strength and wear resistance is used. Although a method of increasing the thickness is effective, wear is increased in the long-term durability as in the present invention. Further, when the diameter of the photoreceptor is reduced in proportion to the downsizing of the apparatus, the blade does not sufficiently follow the curvature, and it becomes difficult to maintain a stable cleaning property. In particular, in the present invention, as a means for improving the durability stability of the photosensitive member, it is necessary to use a photosensitive member having a high hardness layer called a protective layer on the outermost surface of the photosensitive member. It is necessary to propose a cleaning method in which the blade is particularly easy to be scraped and can maintain a sufficient cleaning property without extremely increasing the contact pressure.

  In order to solve these problems, the inventors have focused on the photosensitive member having the protective layer, the cleaning blade, and the electrostatic force due to the polarity of the toner, thereby achieving the present invention.

  The surface of a highly durable photoconductor used in the present invention is likely to be negative, the cleaning blade that abuts is polarized, tends to have a relatively positive charge, and a potential gradient is created between the blade and the photoconductor. The negatively charged toner is considered to be cleaned during the potential gradient.

In the present invention, the negatively chargeable magnetic toner has fine silica powder, and the fine silica powder has a volume-based median diameter (D50) of 0.70 to 3.00 μm and a specific surface area of 1.0. It was possible to obtain a desired effect by using silica of ˜10.0 m ² / g.

  This is because silica, which has a high electronegativity among inorganic fine powders, is used to make the negative chargeability of the toner surface uniform for negatively chargeable toners and to have a greater negative charge effect on the outside of the toner. This is thought to be possible. In addition, the use of silica with a relatively large particle size and a small specific surface area, that is, a nearly spherical shape, compared to commonly used silica increases the negative charging ability and increases the local charge density. Since there is no sharp point that prevents and further facilitates charge diffusion, it is possible to reduce leak sites and to increase electrostatic stability. As a result, the potential gradient between the cleaning blade and the photoconductor is easily attracted to a blade that is more likely to be positively charged than the photoconductor, and drastically improves cleaning performance. This makes it possible to obtain a desired cleaning property even when the amount of penetration of the blade into the photoreceptor and the contact pressure is not excessively large, even when the blade contact portion is worn out in the long-term durability. The toner can be prevented from slipping through, and good cleaning properties and good charging roller contamination prevention properties associated therewith can be obtained.

  As the method for producing the silica fine powder of the present invention, a gas phase method in which a silicon compound such as metal silicon, a silicon halide, and a silane compound is reacted in a gas phase, and a silane compound such as alkoxysilane is water. / There are two types of wet methods: solvent removal from silica sol suspension obtained by hydrolysis and condensation reaction in organic solvent mixed system and drying to form particles. It is preferable to manufacture by a vapor phase method for ease.

  Further, in the toner of the present invention, the silica fine powder of the present invention is used in combination with a hydrophobic inorganic fine powder having a higher ability to impart fluidity to the toner particle surface and a smaller number average primary particle size of the primary particles. It was found that it can be uniformly dispersed in When silica fine powder is not uniformly dispersed, toner deterioration tends to proceed in a high-speed development system. As a result, a decrease in density in the latter half of the endurance tends to occur.

By using a hydrophobic inorganic fine powder having a high fluidity imparting ability to the toner particle surface and a large BET specific surface area, the silica fine powder can be uniformly dispersed in the toner. When the BET specific surface area of the hydrophobic inorganic fine powder is smaller than 50 m ² / g, the silica fine powder is not sufficiently dispersed, which is not preferable. On the other hand, when the BET specific surface area of the hydrophobic inorganic fine powder is larger than 300 m ² / g, the toner is charged up to cause problems such as a decrease in density, which is not preferable.

  As the hydrophobic inorganic fine powder, both a so-called dry method produced by vapor phase oxidation of silicon halide or dry silica called fumed silica, and so-called wet silica produced from water glass or the like are preferable.

  Hydrophobic treatment is performed by using silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, organic titanium compounds, or a combination of two or more. Can be used.

  Metal oxides such as titania and alumina have been studied so far, but in the case of the present invention, in order to obtain the toner attracting effect to the cleaning blade due to the potential gradient between the cleaning blade and the photoreceptor, the toner itself is used. Since it is an essential condition to prevent leakage and increase negative chargeability and increase charge uniformity, large particles of the same kind as inorganic fine powder added in addition to the same hydrophobic silica with the inherent chargeability inherent to the substance A fine silica powder with a diameter is essential.

Further, by adding fine silica powder having a volume-based median diameter (D50) of 0.70 to 3.00 μm and a specific surface area of 1.0 to 10.0 m ² / g to the toner, In addition, it is possible to extremely reduce the contact area between the toner and the photosensitive member, and the toner and the member that contacts the toner, such as a cleaning blade, to prevent deterioration of the toner performance due to rubbing, and to improve the toner fluidity for a long time. Thus, it is possible to obtain stable image stability.

  The particle size distribution in the present invention is measured by a laser diffraction / scattering particle size distribution measuring apparatus LA-920 (manufactured by HORIBA). As a measurement method, for example, about 30 mg of a sample is put in 100 ml of ion-exchanged water as a dispersion medium, and this dispersion is treated with an ultrasonic disperser for 1 minute to obtain a dispersion. This dispersion is dropped into the measurement cell so that the sample concentration is about 80% transmittance. The relative refractive index of the measurement sample and water is set according to the type of the measurement sample, the volumetric particle size distribution is measured using the measurement apparatus, and the median diameter (D50) is obtained.

  As described above, the toner of the present invention is characterized by having a silica fine powder having a volume-based median diameter (D50) of 0.70 to 3.00 μm, more preferably 0.50 to 2.00 μm, and particularly preferably. 0.70 to 1.50 μm.

  When D50 is smaller than 0.70 μm, the effect of reducing the contact area of the toner is small, and deterioration due to friction between the blade and the toner and electrostatic friction between the toners are likely to cause an electric leakage, and the electrostatic stability is impaired. As a result, it is difficult to uniformly increase the cleaning property due to the charging effect between the blade and the photoconductor described above, so that it is difficult to obtain a desired effect in continuous printing, causing C roller contamination, density unevenness, etc. It is easy to cause image defects.

  When D50 is larger than 3.00 μm, the release rate from the toner increases, and the electrostatic cleaning effect and the contact area of the toner cannot be suppressed. Therefore, the desired cleaning effect and image stability can be obtained in continuous printing. It is difficult to continue, and similarly to the above, it causes C roller contamination, and image defects such as density unevenness are likely to occur.

  In particular, with regard to cleaning properties, in addition to the above polar effect, fluidity can be increased by using fine silica powder characterized by a larger particle size and a smaller specific surface area than particles generally used for external addition. It is possible to prevent the toner from staying at the blade abutting portion for a long period of time, and to always form a good toner slip-through preventing layer. .

  In addition, since the toner in the blocking layer is appropriately replaced by increasing the fluidity, extreme pressure is not applied to the blade contact portion, preventing deterioration of the cleaning blade and further improving long-term cleaning stability. It is thought that you can.

  As described above, a silica fine powder having a large particle diameter and a specific specific surface area is required to obtain an optimum cleaning property by the cleaning blade.

  However, in order to obtain the maximum image stability desired by the present invention in addition to the cleaning property, it is necessary to obtain the maximum cleaning property and at the same time reduce the residual transfer toner itself.

  For this purpose, it is necessary to use the same type of silica fine powder while obtaining the effect of the above-described hydrophobic silica for the negatively charged toner. In order to reduce the transfer residual toner, it is most important to make the electrostatic force of the negatively chargeable toner, that is, the chargeability uniform. During development, the charged toner moves from the photosensitive member to the recording medium using a developing bias as a driving force. However, a toner having a uniform charge moves uniformly to the applied electric force, and thus is charged. It is considered that a small toner is less likely to remain on the photoreceptor as a transfer residual toner.

  In order to obtain the above-described charging uniformity effect, the difference between the zeta potential of the silica fine powder and the zeta potential of the negatively chargeable toner particles is 50 mV or less at the pH of the aqueous dispersion of negatively chargeable toner particles used in the present invention. Preferably there is.

  The zeta potential of the negatively chargeable toner particles at the pH of the aqueous dispersion when the negatively chargeable toner particles are dispersed in water represents the surface charge density at the pH of the powder of the toner particles. Therefore, in the present invention, it means that a fine silica powder having a surface charge density almost equivalent to the surface charge density on the surface of the toner particles is used. In general, it is known that when silica fine powder is added to toner particles, intermolecular force such as van der Waals force, electrostatic attractive force, liquid crosslinking force, and the like are generated. In the present invention, by controlling the charge density on the surface of the toner particles and the surface of the silica fine powder to be equivalent, the repulsive force can be exerted in a direction to relieve the attractive force acting on the toner particles and the silica fine powder. It is considered that the interparticle cohesive force was reduced and the charging uniformity was improved.

  When the difference in zeta potential is 50 mV or more, since the electrostatic force of the toner itself has a different potential, an electrostatic difference is generated between the toner and the silica fine powder existing on the surface, and the entire toner Since the charge distribution varies, the attracting effect to the cleaning blade due to the electrostatic action of the present invention may not be sufficiently obtained in the long term.

  The zeta potential of the toner particles and the silica fine powder was measured using an ultrasonic zeta potential measuring device DT-1200 (manufactured by Dispersion Technology). Using pure water as a dispersion, a 0.5 Vol% aqueous solution of toner particles and fine silica powder was prepared. If necessary, after adding 0.4% by mass of a nonionic dispersant that does not affect the zeta potential to the particle concentration, the mixture is dispersed for 3 minutes with an ultrasonic disperser, and then defoamed for about 10 minutes. Stir to make a dispersion. The pH of the supernatant was measured simultaneously with the measurement of the toner particles. When measuring the fine silica powder, this dispersion was titrated with 1N HCl or 1N KOH as necessary to adjust the pH value of the supernatant of the toner particles, and the zeta potential was measured using the above apparatus.

  As described above, in the present invention, in addition to hydrophobic silica, silica having a particle size and specific surface area in a specified range is contained, so that the residual toner can be reduced by improving charging uniformity and the toner slipping layer can be effectively removed. By improving the cleaning effect due to the formation, it is possible to achieve both stable images and cleaning properties even during long-term durability.

  As shown in FIG. 2, the slip-through preventing layer described above is composed of toner and finer particles, in the case of the present invention, hydrophobic silica and silica fine particles having a particle size and specific surface area in the above-mentioned range. Although it is considered that powder is present, hydrophobic silica is generally used several nanometers to several tens of nanometers, and when forming a blocking layer, it is considered that it exists only in the part closest to the contact part, It is considered that a sufficient blocking layer cannot be formed. Therefore, for the purpose of preventing the toner from slipping through and increasing the local pressure on the blade at the contact portion, particles having a size close to the particle diameter of the toner form a blocking layer while maintaining fluidity. Is effective in maintaining long-term cleaning properties.

  Further, the cleaning blade of the present invention and the tip of the abutting portion upstream in the circumferential direction of the photosensitive member are point A in FIG.

  In the present invention, by setting the distance between A and B in FIG. 2 to 0.3 to 4.0 mm, it is possible to optimally maintain the balance between the toner blocking layer formation of the present invention and the retention control over a long period of time. Desirable cleaning stability and image stability can be obtained.

  If the thickness is shorter than 0.3 mm, a sufficient blocking layer cannot be formed and the cleaning property is insufficient, and if it is larger than 4 mm, the retention of the blocking layer becomes too high, so that sufficient fluidity can be obtained even with the toner of the present invention. It is difficult, a load is applied to the blade, and the durability of the blade is somewhat inferior.

In the present invention, by externally adding the silica fine powder having a large particle size as described above, the apparent toner particle size including the external additive is increased, and the diameter of the particles forming the blocking layer has a wider width. By forming an effective blocking layer, the cleaning properties are dramatically improved. Further, the shape of silica satisfying a volume-based median diameter (D50) of 0.70 to 3.00 μm and a specific surface area of 1.0 to 10.0 m ² / g tends to approach a sphere. Since the particles present on the toner surface are nearly spherical, the toner of the present invention has high fluidity, preventing extreme pressure from being applied to the blade contact portion, and realizing high durability of the cleaning blade. As a result, the effect of preventing the charging member from being contaminated and the effect of enhancing the durability stability of the image are obtained.

In a more preferred embodiment, the silica fine powder contained in the toner is silica having a volume-based median diameter (D50) of 0.70 to 3.00 μm and a specific surface area of 1.0 to 10.0 m ² / g. While satisfying, the volume distribution integrated value of 1/2 times or less of the volume-based median diameter (D50) of the fine powder is 0.5 to 20.0%, and the volume distribution integrated value of 2 times or more is 0.5 Desirably, it is ˜20.0%.

  In other words, when forming the toner slip-through prevention layer of the blade portion by giving a width to the particle size distribution, the prevention layer is formed to a minute region where the loose large particle size silica is difficult to enter the toner at the tip of the prevention layer. In addition, various gaps between the toners can be effectively filled, and as a result, a close-packed blocking layer can be formed, and the cleaning property can be further improved.

  Further, when the surface of the photoreceptor described above as a more preferable embodiment with respect to the cleaning property is roughened, the cleaning property and the durability of the cleaning blade are greatly improved. On the other hand, the surface of the roughened photoreceptor surface is improved. External additives, toner fine powder, etc. accumulate in the grooves, and the particles that enter the grooves are difficult to scrape off with a cleaning blade. If accumulated over a long period of time, the toner behavior is uneven during fusion or development. The resulting image tends to deteriorate and fog and the like tend to deteriorate.

To solve these problems, the toner of the present invention contains a fine silica powder having a median diameter of 0.70 to 3.00 μm and a specific surface area of 1.0 to 10.0 m ² / g. The fine toner powder and external additives accumulated in the groove on the surface of the photoconductor are scraped off, and the toner containing silica fine powder on the surface gets into the groove of the photoconductor, so that the fine toner powder and the toner are released. It is possible to prevent re-entry of particles, such as external additives and charged products, that disturb the original behavior of the toner into the photoreceptor groove.

  In order to obtain these effects, the median diameter is preferably 0.80 to 2.00 μm, more preferably 0.70 to 1.50 μm in relation to the unevenness of the photoreceptor.

Further, in order to prevent the same toner from staying in the toner slip-off preventing layer for a long time and to always obtain the optimum slip-through preventing effect, the specific surface area is preferably 1.0 to 8.0 m ² / g, 2.0 ˜8.0 m ² / g is more preferable.

Even when such a roughened photoreceptor is used, the silica fine powder contained in the toner is silica having a volume-based median diameter (D50) of 0.70 to 3.00 μm and a specific surface area of 1. 1.0 to 10.0 m ² / g, the volume distribution integrated value of 1/2 times or less of the volume-based median diameter (D50) of the fine powder is 0.5 to 20.0%, and the double diameter The above volume distribution integrated value is 0.5 to 20.0%, that is, by having a certain particle size distribution, sufficient particles such as the above unnecessary components can be obtained even in various photoconductor surface states. It is possible to obtain a scraping effect and a re-entry prevention effect, and it is possible to widen the range of adaptation to the surface state of the photoreceptor.

  Next, the photoconductor will be described. The structure of the photoreceptor in the present invention is a structure in which a charge generation layer and a charge transport layer are laminated in this order as a photosensitive layer on a support, or conversely, a structure in which a charge transport layer and a charge generation layer are laminated in this order. Any configuration of a single layer in which a material and a charge transport material are dispersed in a binder resin can be employed. A surface protective layer is formed on the photosensitive layer. In particular, a configuration in which a protective layer is formed on a function-separated photosensitive layer in which a charge generation layer and a charge transport layer are laminated in this order is preferable.

  In addition, the protective layer in the present invention needs to have a charge transport ability after curing, but when the compound having the unsaturated polymerizable functional group is used, the compound does not have a charge transport ability. In addition, it is preferable to secure the charge transporting ability by adding a charge transporting material or a conductive material. On the other hand, this is not the case when the compound having an unsaturated polymerizable functional group itself has a charge transporting ability. However, from the viewpoint of the film hardness of the protective layer and various electrophotographic characteristics, it is more preferable to use a compound having the charge transport ability such as the latter. Further, among compounds having charge transporting ability, compounds having hole transporting ability are more preferable from the viewpoint of versatility of electrophotographic processes and materials.

The electrophotographic photosensitive member used in the present invention has a universal hardness value (HU) of 150 N / mm ² or more and 240 N / mm ² or less in a 25 ° C./50% RH environment on its surface, and an elastic deformation rate of 44% or more and 65. % Or less.

  Although it is difficult to completely separate the above-mentioned universal hardness value (HU) from the elastic deformation rate, the universal hardness value (HU) and the elastic deformation rate of the photoreceptor used in the present invention are within the above ranges. In addition, while maintaining the abrasion resistance (high durability) of the photoreceptor, it is possible to optimally control the rubbing property with the blade as the cleaning member and the formation of the toner blocking layer of the present invention. It has been found that the cleaning property can be maintained even when continuous printing is performed.

When the universal hardness value HU of the photoconductor is larger than 240 N / mm ² , that is, when the photoconductor is too hard, even if the elastic modulus is high, the resulting elastic deformation amount is relatively small, and the photoconductor In a portion where a large pressure is locally applied, such as a contact portion with a cleaning blade or a charging member that is in contact with the body, when the toner or paper powder is sandwiched, the photoreceptor and the cleaning blade are easily damaged, and the present invention Even when this toner is used, it is difficult to obtain sufficient fluidity, and the durability of the durable image and the cleaning property are slightly inferior.

  When the universal hardness value HU of the photosensitive member is larger than 240 N / mm 2 and the elastic modulus is low, the amount of elastic deformation is further reduced, so that the above tendency increases and it becomes difficult to obtain desired performance.

  That is, the universal hardness (HU) of the photoconductor is not necessarily preferable to have a large value in order to combine excellent wear resistance, high durability, and cleaning properties.

Further, when the universal hardness value HU of the photosensitive member is smaller than 150 N / mm ² , the plastic deformation rate tends to be high, and even when the elastic deformation rate is 44 to 65% which is the range of the present invention, the photosensitive member is also sensitive. It is easy to cause body wear and distortion, and it is difficult to maintain the optimum position of contact pressure and contact angle with the cleaning member for a long period of time, and a toner having a large blocking layer formation width is used as in the present invention. Even in this case, it is difficult to maintain an effective blocking layer, and cleaning performance and charging member contamination are liable to occur during mass printing, and image durability stability is lacking. When the elastic deformation rate is small, the influence of the plastic deformation amount is further increased, and the above tendency is further increased. Even if the elastic deformation rate can be increased, if the universal hardness of the photoreceptor is smaller than 150 N / mm ² , the amount of plastic deformation increases, so that the desired image durability and cleaning properties can be improved. Hard to get.

  In the present invention, the universal hardness value (HU) and elastic deformation rate of the surface of the electrophotographic photosensitive member were measured using a microhardness measuring apparatus Fischerscope H100V (manufactured by Fischer) in an environment of 25 ° C./50% RH. Value. This Fischer scope H100V has an indenter in contact with the object to be measured (the surface of the electrophotographic photosensitive member), continuously applies a load to the indenter, and directly reads the indentation depth under the load to obtain continuous hardness. Device.

  In the present invention, a Vickers square pyramid diamond indenter having a facing angle of 136 ° is used as the indenter, and the final (final load) of the load continuously applied to the indenter is 6 mN when the measurement object is an electrophotographic photosensitive member. The time (holding time) for holding the indenter with a final load of 6 mN was 0.1 seconds. The measurement points were 273 points.

  An outline of the output chart of the Fischer scope H100V (Fischer) is shown in FIG. FIG. 4 shows an example of an output chart of a Fischer scope H100V (manufactured by Fischer) when the electrophotographic photosensitive member used in the present invention is a measurement object. 3 and 4, the vertical axis represents the load F (mN) applied to the indenter, and the horizontal axis represents the indentation depth h (μm). FIG. 3 shows the results when the load applied to the indenter is increased stepwise to maximize the load (A → B) and then decreased gradually (B → C). FIG. 4 shows the results when the load applied to the indenter is increased stepwise to finally make the load 6 mN, and then the load is decreased stepwise.

  The universal hardness value (HU) can be obtained by the following equation from the indentation depth of the indenter when a final load of 6 mN is applied to the indenter. In the following formula, universal hardness value (HU) means universal hardness (universal hardness value (HU)), Ff means final load, and Sf is indenter indentation when the final load is applied. The surface area of the indented portion is meant, and hf (μm) means the indentation depth of the indenter when the final load is applied.

  The elastic deformation rate is the amount of work (energy) performed by the indenter with respect to the measurement target (electrophotographic photosensitive member surface), that is, energy due to increase or decrease of the load on the measurement target of the indenter (electrophotographic photosensitive member surface). It can be obtained from the change of. Specifically, a value (We / Wt) obtained by dividing the elastic deformation work We by the total work Wt is the elastic deformation rate. Note that the total work amount Wt is the area of the region surrounded by A-B-D-A in FIG. 3, and the elastic deformation work amount We is the area of the region surrounded by C-B-D-C in FIG. It is.

  Examples of the material for the cleaning blade used in the present invention include polyurethane rubber, neoprene rubber, chloroprene rubber, silicone rubber, and fluorine rubber. In order to obtain the toner attracting effect to the blade portion due to the potential gradient with the photoconductor obtained in the present invention, urethane rubber having excellent charging ability by friction with the photoconductor from the viewpoint of easily having polarity is preferable. Urethane rubber is also preferable in that it has high hardness and high elasticity, and is excellent in wear resistance, mechanical strength, oil resistance, ozone resistance, etc. As the urethane rubber, a polyurethane generally synthesized through an addition reaction of an isocyanate with a polyol and various hydrogen-containing compounds is used. As the polyol component, a polyether polyol such as polypropylene glycol or polytetramethylene glycol, or an adipate type is used. Polyester polyols such as polyols, polycaprolactam polyols, polycarbonate polyols, etc., and polyisocyanate components such as tolylene diisocyanate, 4,4′diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluidine diisocyanate and other aromatic polyisocyanates , Hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, dicyclohexylme It is manufactured by preparing a urethane prepolymer using an aliphatic polyisocyanate such as diisocyanate, adding a curing agent to the urethane prepolymer, injecting it into a predetermined mold, crosslinking and curing, and then aging at room temperature. Yes. As the curing agent, a dihydric alcohol such as 1,4-butanediol and a trihydric or higher polyhydric alcohol such as trimethylolpropane or pentaerythritol are used in combination.

  The support member is not particularly limited, and examples thereof include those manufactured from rigid metals, elastic metals, plastics, ceramics, and the like. Among these supporting members, a rigid metal is preferably used.

  In the embodiment of the present invention, the amount of penetration δ of the cleaning blade into the photosensitive member is 0.2 to 2.0 mm, and the contact angle Ψ between the cleaning blade and the photosensitive member is 10 ° to 40 °. This is necessary for effective formation of durability and a cleaning prevention layer, and control of the polarizability between the blade and the photoreceptor.

  When the intrusion amount is smaller than 0.2 mm or when the contact angle is smaller than 10 °, the formation of the blocking layer tends to be insufficient, and the polarization between the photoreceptor and the blade is small, which is used for the toner of the present invention. Since the electrostatic cleaning assisting effect due to the large particle size silica is small, the cleaning performance is slightly inferior, and when the intrusion amount is larger than 2.0 mm or the contact angle is larger than 40 °, it is locally at the contact portion with the blade. Even when a highly fluid toner such as the present invention is used, the toner is likely to be caught between the blade and the photoconductor, and even on a high-hardness photoconductor, the photoconductor is likely to be damaged. Become.

  Further, the micro hardness of the cleaning blade of the present invention needs to be 55 degrees or more and 82 degrees or less in order to have blade durability, load on the photosensitive member, and cleaning performance.

  When the micro hardness is less than 55 degrees, the blade is likely to be worn during high-speed mass printing, and when it exceeds 82 degrees, the load on the photosensitive member is large, and the silica fine powder on the toner surface of the present invention is attracted to the blade. It becomes difficult to obtain the electrostatic cleaning effect and the blocking layer effect for a long term.

  The micro hardness is obtained by measuring the load when a needle with a diameter of 0.16 mm and a height of 0.5 mm is pressed against a rubber blade in an environment of a temperature of 23 ° C. and a humidity of 50% to determine the hardness of the surface portion of the blade. It was measured using a micro hardness tester SMD-1. The measurement was performed with an average of 10 points.

  Hereinafter, the electrophotographic photosensitive member used in the present invention will be described in more detail, including its manufacturing method.

  In order to obtain an electrophotographic photosensitive member having a surface universal hardness value (HU) and elastic deformation rate within the above ranges, the surface layer of the electrophotographic photosensitive member is formed of a hole transporting compound having a chain polymerizable functional group. It is particularly effective to form the polymer by polymerizing and crosslinking a hole transporting compound having two or more chain polymerizable functional groups (in the same molecule). The surface layer of the electrophotographic photosensitive member means a layer located on the outermost surface of the electrophotographic photosensitive member, in other words, a layer that is located farthest from the support.

  First, a method for forming a surface layer using a hole transporting compound having a chain polymerizable functional group will be described more specifically.

  The surface layer is coated with a hole transporting compound having a chain polymerizable functional group and a solvent, and if necessary, a surface layer coating solution further containing a binder resin, and the hole transport having the chain polymerizable functional group is applied. It can be formed by polymerizing (and crosslinking) the functional compound and curing the applied coating solution for the surface layer.

  In the present invention, the “hole transportable compound having a chain polymerizable functional group” refers to a compound in which a chain polymerizable functional group is chemically bonded to a part of the molecule of the hole transportable compound.

  Chain polymerization refers to the former form of polymerization reaction when the polymer formation reaction is largely divided into chain polymerization and sequential polymerization. Specifically, the reaction form mainly passes through intermediates such as radicals or ions. It means unsaturated polymerization, ring-opening polymerization or isomerization polymerization in which the reaction proceeds.

  The chain polymerizable functional group means a functional group capable of the above reaction form. Unsaturated polymerization is a reaction in which unsaturated groups such as C═C, C≡C, C═O, C═N, C≡N, and the like are polymerized by radicals or ions, among which C═C Is the main.

  Ring-opening polymerization is a reaction in which unstable cyclic structures such as carbocycles, oxo rings, and nitrogen heterocycles open and repeat polymerization to form chain polymers, and ions are active species. Most of them act as

  In the present invention, among the hole transporting compounds having the chain polymerizable functional group, a hole transporting compound having two or more chain polymerizable functional groups (in the same molecule) is preferable.

  The presence of two or more chain polymerization reaction points makes it possible to improve the charging performance uniformity on the surface of the photoconductor two-dimensionally and three-dimensionally. When the blade and the photoconductor are rubbed, The potential gradient of the toner can be kept constant, without disturbing the formation of the blocking layer, and by obtaining a dense charging point, the polarization of the blade by rubbing is promoted, and the toner attracting effect can be maximized. It is considered possible.

  When applying the surface layer coating solution, for example, a coating method such as a dip coating method (dip coating method), a spray coating method, a curtain coating method, or a spin coating method can be used. Among these coating methods, the dip coating method and the spray coating method are preferable from the viewpoints of efficiency and productivity.

  Examples of a method for polymerizing (and crosslinking) a hole transporting compound having a chain polymerizable functional group include a method using heat, light such as visible light and ultraviolet light, and radiation such as electron beam and γ ray. If necessary, the surface layer coating solution may contain a polymerization initiator.

  In addition, as a method for polymerizing (and crosslinking) a hole transporting compound having a chain polymerizable functional group, a method using radiation such as an electron beam or γ-ray, particularly an electron beam is preferable. This is because polymerization by radiation does not particularly require a polymerization initiator. By polymerizing (and cross-linking) a hole transporting compound having a chain polymerizable functional group without using a polymerization initiator, a surface layer of a very high purity three-dimensional matrix can be formed, and good electrons can be formed. An electrophotographic photoreceptor showing photographic characteristics can be obtained. Further, polymerization with an electron beam among radiations causes very little damage to the electrophotographic photosensitive member due to irradiation, and can exhibit good electrophotographic characteristics.

  A hole transporting compound having a chain polymerizable functional group is polymerized (and crosslinked) by irradiation with an electron beam to obtain an electrophotographic photosensitive member of the present invention having a universal hardness value (HU) and an elastic deformation rate in the above ranges. For this, it is important to consider the irradiation conditions of the electron beam.

  When irradiating an electron beam, it can carry out using accelerators, such as a scanning type, an electro curtain type, a broad beam type, a pulse type, and a laminar type. The acceleration voltage is preferably 300 kV or less, and more preferably 200 kV or less. The irradiation dose is preferably in the range of 0.1 to 100 Mrad, and more preferably in the range of 0.5 to 20 Mrad. If the acceleration voltage or irradiation dose is too large, the electrical characteristics of the electrophotographic photosensitive member may deteriorate. If the irradiation dose is too small, polymerization (and crosslinking) of the hole transporting compound having a chain polymerizable functional group may be insufficient, and curing of the surface layer coating solution may be insufficient.

  In order to accelerate the curing of the coating solution for the surface layer, an object to be irradiated (electron beam is irradiated during polymerization (and crosslinking) of a hole transporting compound having a chain polymerizable functional group by electron beam. It is preferable to heat the one). The timing of heating may be at any stage before, during or after the electron beam irradiation, but the irradiated object is kept at a constant temperature while the radical of the hole transporting compound having a chain polymerizable functional group is present. It is preferable that Heating is preferably performed so that the temperature of the irradiated object is from room temperature to 250 ° C. (more preferably from 50 to 150 ° C.). If the heating temperature is too high, the material of the electrophotographic photosensitive member may be deteriorated. If the heating temperature is too low, the effect obtained by heating becomes poor. The heating time is preferably about several seconds to several tens of minutes, specifically 2 seconds to 30 minutes.

  The atmosphere at the time of electron beam irradiation and heating of the irradiated object may be any of the atmosphere, an inert gas such as nitrogen or helium, or a vacuum, but can suppress radical deactivation due to oxygen. In that respect, it is preferably in an inert gas or in a vacuum.

  The thickness of the surface layer of the electrophotographic photoreceptor is preferably 30 μm or less, more preferably 20 μm or less, more preferably 10 μm or less, and more preferably 7 μm or less from the viewpoint of electrophotographic characteristics. More preferably. On the other hand, from the viewpoint of durability of the electrophotographic photosensitive member, it is preferably 0.5 μm or more, and more preferably 1 μm or more.

  Next, the electrophotographic photoreceptor of the present invention will be described in more detail including layers other than the surface layer. As described above, the electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a support. The photosensitive layer is separated into a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material even if it is a single layer type photosensitive layer containing the charge transporting material and the charge generating material in the same layer. A laminated type (functional separation type) photosensitive layer may be used, but a laminated type photosensitive layer is preferred from the viewpoint of electrophotographic characteristics. The laminated photosensitive layer has a normal layer type photosensitive layer laminated in the order of the charge generation layer and the charge transport layer from the support side, and a reverse layer type photosensitive layer laminated in the order of the charge transport layer and the charge generation layer from the support side. However, a normal photosensitive layer is preferred from the viewpoint of electrophotographic characteristics. Further, the charge generation layer may have a laminated structure, and the charge transport layer may have a laminated structure.

  Moreover, what is necessary is just to make it the universal hardness value (HU) and elastic deformation rate of the surface of an electrophotographic photosensitive member exist in the said range regardless of what kind of layer constitution.

  As the support, any material may be used as long as it exhibits conductivity (conductive support), and any material that does not affect the measurement of the surface hardness of the electrophotographic photosensitive member. For example, aluminum, copper, A support made of a metal (made of alloy) such as chromium, nickel, zinc, and stainless steel can be used. Moreover, the said metal support body and plastic support body which have a layer in which aluminum, an aluminum alloy, an indium oxide tin oxide alloy etc. were formed into a film by vacuum deposition can also be used. In addition, a support in which conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles are impregnated into plastic or paper together with an appropriate binder resin, or a plastic support having a conductive binder resin, etc. Can also be used. Examples of the shape of the support include a cylindrical shape (drum shape) and a belt shape, and a cylindrical shape is preferable.

  The surface of the support may be subjected to cutting treatment, roughening treatment, alumite treatment, etc. for the purpose of preventing interference fringes due to scattering of laser light or the like.

  As described above, between the support and the photosensitive layer (charge generation layer, charge transport layer) or an intermediate layer described later, for the purpose of preventing interference fringes due to scattering of laser light or the like and covering the scratches on the support An electrically conductive layer may be provided.

  The conductive layer can be formed by dispersing conductive particles such as carbon black, metal particles, and metal oxide particles in a binder resin. The thickness of the conductive layer is preferably 1 to 40 μm, and more preferably 2 to 20 μm.

  Further, as described above, an intermediate layer having a barrier function or an adhesive function may be provided between the support or the conductive layer and the photosensitive layer (charge generation layer, charge transport layer). The intermediate layer is formed for the purpose of improving the adhesion of the photosensitive layer, improving the coating property, improving the charge injection property from the support, and protecting the photosensitive layer from electrical breakdown.

  The intermediate layer is made of materials such as polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, N-methoxymethylated 6 nylon, copolymer nylon, glue and gelatin. Can be formed. The film thickness of the intermediate layer is preferably 0.1 to 2 μm.

  Examples of the charge generating material used in the electrophotographic photosensitive member of the present invention include selenium-tellurium, pyrylium, thiapyrylium dyes, various central metals, and various crystal systems (α, β, γ, ε, X type, etc.). Phthalocyanine pigments having an Examples thereof include amorphous silicon (described in JP-A No. 54-143645). These charge generation materials may be used alone or in combination of two or more.

  As the charge transport material used in the electrophotographic photoreceptor of the present invention, in addition to the hole transport compound having the chain polymerizable functional group, for example, a heterocyclic ring such as poly-N-vinylcarbazole and polystyrylanthracene, Polymer compounds having condensed polycyclic aromatics, heterocyclic compounds such as pyrazoline, imidazole, oxazole, triazole, carbazole, triarylalkane derivatives such as triphenylmethane, triarylamine derivatives such as triphenylamine, Examples include phenylenediamine derivatives, N-phenylcarbazole derivatives, stilbene derivatives, hydrazone derivatives, and the like.

  When the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer, the charge generation layer is coated with a coating solution for a charge generation layer obtained by dispersing a charge generation material together with a binder resin and a solvent, and dried. Can be formed. Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a vibrating ball mill, a sand mill, a roll mill, an attritor, a liquid collision type high-speed disperser, and the like. The ratio between the charge generating material and the binder resin is preferably in the range of 1: 0.3 to 1: 4 (mass ratio). Alternatively, the charge generation material can be formed alone by a vapor deposition method or the like to form a charge generation layer. The thickness of the charge generation layer is preferably 5 μm or less, and more preferably 0.1 to 2 μm.

  When the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer, a charge transport layer, particularly a charge transport layer that is not a surface layer of an electrophotographic photosensitive member, is obtained by dissolving a charge transport material and a binder resin in a solvent. It can form by apply | coating the coating liquid for charge transport layers, and drying. In addition, among the above charge transport materials, those having film formability alone can be formed as a charge transport layer by itself without using a binder resin. The ratio between the charge transport material and the binder resin is preferably in the range of 2: 8 to 10: 0 (mass ratio), and more preferably in the range of 3: 7 to 10: 0 (mass ratio). If the amount of the charge transporting material is too small, the charge transporting ability is lowered, and the sensitivity may be lowered or the residual potential may be raised.

  The thickness of the charge transport layer, particularly the charge transport layer that is not the surface layer of the electrophotographic photosensitive member, is preferably 1 to 50 μm, more preferably 1 to 30 μm, still more preferably 3 to 30 μm. It is especially preferable that it is ˜20 μm.

  When the charge transport material and the charge generation material are contained in the same layer, the layer is coated with a coating solution for the layer obtained by dispersing the charge generation material and the charge transport material together with a binder resin and a solvent. It can be formed by drying.

  Examples of the binder resin used in the photosensitive layer (charge transport layer, charge generation layer) include vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylate ester, methacrylate ester, vinylidene fluoride, and trifluoroethylene. Polymer or copolymer, polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin, polycarbonate resin, polyarylate resin, polyester resin, polysulfone resin, polyphenylene oxide resin, polyurethane resin, cellulose Resins, phenol resins, melamine resins, silicon resins, epoxy resins, and the like can be given. These can be used singly or in combination of two or more as a mixture or copolymer.

  Further, since the photoreceptor of the present invention has a higher surface hardness than general photoreceptors as described above, it is excellent in abrasion resistance. However, it is preferable that the surface of the photoreceptor is roughened in terms of cleaning properties.

  Specifically, the surface shape of the electrophotographic photoreceptor is such that the surface roughness Rz (10-point average surface roughness) is 0.2 μm or more and 3.0 μm or less, the surface unevenness average interval Sm is 10 to 100 μm, and the surface When the sharpness RKu is in the range of 3 <Rku <20, the cleaning property is further improved, and therefore it is preferable to perform the roughening treatment.

  When Rz is smaller than 0.2 μm, the contact area between the cleaning blade and the surface of the photosensitive member becomes too large, and problems such as blade chatter, blade wear and chipping are likely to occur, and good cleaning performance is achieved as the number of durable sheets increases. It becomes difficult to obtain. Similarly, even when Sm is larger than 100 μm, the adhesion between the cleaning blade and the surface of the photoreceptor is increased, and it is difficult to maintain excellent cleaning properties through durability. On the contrary, when Rz is larger than 3 μm or Sm is smaller than 10 μm, the cleaning blade cannot sufficiently contact the surface of the photoreceptor, and the effect of blocking the transfer residual toner is reduced, and the unevenness of the toner of the present invention is reduced. The effect of preventing re-entry of a substance that hinders normal charging is reduced, and a cleaning failure such as slipping through easily occurs.

  Next, the parameter Rku representing the surface shape will be described. Rku (or Kurtosis) is a measure of the sharpness of the ADF (Modulation Density Function) curve and the surface “Spikins”, and Rku = 3 in a state where the photoreceptor surface has a normal distribution. Yes, the value is farther from 3 as the sharpness is biased in either the upper or lower direction. Rku is calculated from the following equation. Here, n is the number of elements Yi in the profile, and Rq is the root mean square roughness.

  When Rku is 3 or less, the contact area with the cleaning blade is reduced because the convex portions of the surface shape of the photoreceptor have a sharp shape. For this reason, even if Rz and Sm are within the above ranges, there may be a situation in which slipping-out occurs due to the weak blocking force of the transfer residual toner by the cleaning blade. In addition, since the contact area is small, it is difficult to remove the discharge products by the cleaning blade, and image flow is likely to occur. Further, since the surface shape of the photosensitive member is maintained even after the endurance, the edge of the cleaning blade is severely worn at a portion having a high kurtosis on the surface of the photosensitive member, which may cause a problem in cleaning performance after the endurance.

  On the other hand, when Rku is larger than 3, the contact area between the blade and the surface of the photoreceptor becomes appropriate, and good cleaning properties are obtained.

  As described above, it is important to appropriately set the ranges of Rz, Sm, and Rku in order to make full use of a drum having a low wear rate as in the present invention. Those having a large wear rate on the surface of the photosensitive member are not significantly involved in the cleaning performance after endurance because the shape cannot be maintained even if the surface shape is determined in the initial stage. Since the surface is always refreshed, discharge products and the like do not accumulate, and the friction coefficient between the cleaning blade and the photoreceptor surface does not increase so much. On the other hand, in the photoconductor having high durability as in the present invention, discharge products or the like are accumulated, or they must be removed by the blade, and the load on the blade is increased, causing problems such as blade wear, chattering, and sag. Let Therefore, since the surface shape of a photosensitive drum having a very low wear rate is maintained even after long-term durability, the first surface shape determination is important.

  In particular, the toner used in the present invention scrapes out a substance that inhibits normal charging present on the irregularities of the photosensitive member due to the relatively large particle size of silica fine powder entering the irregularities on the surface, and further penetrates the surface. In addition, the toner of the present invention is preferentially attracted to the blade at the contact portion with the cleaning blade because of its large negative chargeability as described above, and therefore there is no unnecessary substance on the surface of the photoreceptor after cleaning. It is thought that it will be in a refreshed state.

  In the present invention, the surface roughness of the surface of the electrophotographic photosensitive member is measured as follows using a contact type surface roughness measuring machine (trade name: Surfcorder SE3500, manufactured by Kosaka Laboratory Ltd.).

  Detector: R2 μm, 0.7 mN diamond needle, filter: 2CR, cutoff value: 0.8 mm, measurement length: 2.5 mm, feed rate: 0.1 mm, 10 points defined by JIS standard B0601 Data of average surface roughness Rz was processed. The average spacing Sm of the surface irregularities is an arithmetic average value obtained from the following equation measured under the same conditions.

Ｓｍｉ：凹凸の間隔
ｎ：基準長さ内で凹凸の間隔の個数

Smi: spacing of irregularities n: number of irregularities within the reference length

  Rku is a value measured by a Newview 5000 system of Zygo and analyzed by Metropro. During the measurement, a 10X Mirau interference objective lens was used.

  Next, FIG. 5 shows an example of a polishing machine including a polishing sheet as roughening means for controlling the surface shape of the electrophotographic photosensitive member of the present invention. The abrasive sheet is a sheet in which abrasive grains are dispersed in a binder resin and applied to a substrate. The polishing sheet 5-5 is wound around a hollow shaft a, and a motor (not shown) is disposed in a direction opposite to the direction in which the sheet is fed to the shaft a so that tension is applied to the polishing sheet 5-5. The polishing sheet 5-5 is fed in the direction of the arrow, passes through the backup roller 5-6 via the guide rollers 5-1, 5-2, and the polished sheet is shown via the guide rollers 5-3, 5-4. It is wound around the winding means 5-7 by a motor that does not. The polishing is basically performed by constantly pressing an untreated polishing sheet against the surface of the photoconductor to roughen the surface of the photoconductor.

  FIG. 6 shows a schematic view of an abrasive discharge means for controlling the surface shape by another method. It comprises an abrasive discharge device 6-1, a driving means (not shown) for rotating the electrophotographic photosensitive member 13 in the direction of arrow c, and an exhaust device (not shown). Abrasive grains are sprayed from the discharge device 6-1 to the surface of the electrophotographic photosensitive member 13 rotated at a desired rotational speed, and the discharge device 6-1 or the electrophotographic photosensitive member 13 moves in the thrust direction. The entire surface of the electrophotographic photoreceptor is roughened. At that time, the abrasive grains discharged from the discharge device 6-1 are sucked by an exhaust device (not shown). The abrasive grains may be reused. The abrasive grains used in the roughening step are preferably metal, glass, resin or the like. Among them, the electrophotographic photosensitive member surface shape that can obtain the desired shape as described above may be selected. In the case of metal, the abrasive grain size is preferably 1 to 100 μm, and more preferably 5 to 60 μm. In the case of resin, 30-200 micrometers is preferable. The shape of the abrasive grains is preferably spherical if it is indeterminate because deep recesses are likely to occur on the surface of the photoreceptor. In roughening, a plurality of particles having different particle diameters, shapes, and materials may be used.

  The surface shape control means described above has described a method for obtaining a desired surface shape by forming a film on the surface of the photoconductor and performing a roughening treatment after curing. There is no problem even if a means for curing is formed after forming the film.

  Further, in the present invention, the use of magnetic iron oxide, which is a dielectric, makes it easy to break up the toner agglomerates when an electric field is applied, so that the latent image can be reproduced faithfully without protruding. In view of durability and stability in a high-speed machine, it is necessary to contain magnetic iron oxide. Furthermore, by including magnetic iron oxide in the toner particles, the surface resistance of the toner particles can be made equal to the surface resistance of the silica fine powder. As a result, charge transfer between the toner particle surface and the silica fine powder is facilitated, and the effect of alleviating the cohesiveness between particles can be expressed more effectively.

  The number average particle diameter of the magnetic iron oxide of the present invention is preferably 0.05 to 1.00 μm, more preferably 0.10 to 0.60 μm.

  As the magnetic iron oxide, iron oxide such as magnetite, maghemite, and ferrite is used. In addition, the magnetic iron oxide of the present invention is preferably subjected to a treatment to loosen the magnetic iron oxide by applying shear to the slurry during production for the purpose of improving the fine dispersibility in the toner particles.

  In the present invention, the amount of magnetic iron oxide to be contained in the toner is preferably 20 to 200 parts by mass, more preferably 30 to 150 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the binder resin used in the present invention include polystyrene; a styrene-substituted homopolymer such as poly-p-chlorostyrene and polyvinyltoluene; a styrene-p-chlorostyrene copolymer and a styrene-vinyltoluene copolymer. Styrene-vinyl naphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ester Styrene copolymers such as ter copolymers, styrene-vinyl ethyl ether copolymers, styrene-vinyl methyl ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers. Polymer; polyvinyl chloride, pheno Resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin , Coumarone indene resin and petroleum resin.

  In the present invention, the above binder resins can be used alone or in admixture of two or more and partially reacted.

  The components of the polyester resin used in the present invention are as follows.

  Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, bisphenol represented by formula (1) and derivatives thereof:

(Wherein R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 to 10),
And diols represented by formula (2);

  Examples of the divalent acid component include benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride or anhydrides thereof, lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid. Acids or anhydrides thereof, lower alkyl esters; alkenyl succinic acids or alkyl succinic acids such as n-dodecenyl succinic acid and n-dodecyl succinic acid, or anhydrides, lower alkyl esters thereof; fumaric acid, maleic acid, citraconic acid, itaconic acid Dicarboxylic acids such as unsaturated dicarboxylic acids or anhydrides thereof, lower alkyl esters;

  Examples of the trihydric or higher polyhydric alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butane. Triol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene, etc. Is mentioned.

  Examples of the trivalent or higher polyvalent carboxylic acid component in the present invention include trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5, 7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylene Carboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, empole trimer acid, and their anhydrides, lower alkyl esters; formula (3)

（式中、Ｘは炭素数３以上の側鎖を１個以上有する炭素数５〜３０のアルキレン基又はアルケニレン基）
で表されるテトラカルボン酸等及びこれらの無水物、及び低級アルキルエステル等の多価カルボン酸類及びその誘導体が挙げられる。

(Wherein X is an alkylene group or alkenylene group having 5 to 30 carbon atoms having one or more side chains having 3 or more carbon atoms)
And polycarboxylic acids such as lower carboxylic esters and derivatives thereof.

  Examples of the vinyl monomer for producing the vinyl resin include the following.

  Styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dimethyl Styrene, pn-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene Styrene and its derivatives such as: styrene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; unsaturated polyenes such as butadiene and isoprene; halogenated such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride Vinyls: Vinyl acetate, vinyl propionate, vinyl benzoate Vinyl esters such as: methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacrylic acid Α-methylene aliphatic monocarboxylic acid esters such as phenyl, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-acrylate Acrylic esters such as octyl, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; vinyl methyl ether Vinyl ethers such as vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone N-vinyl compounds such as these; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide.

  In addition, unsaturated dibasic acids such as maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid; maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride, etc. Unsaturated dibasic acid anhydride; maleic acid methyl half ester, maleic acid ethyl half ester, maleic acid butyl half ester, citraconic acid methyl half ester, citraconic acid ethyl half ester, citraconic acid butyl half ester, itaconic acid methyl half ester, Alkenyl succinic acid half ester, fumaric acid methyl half ester, mesaconic acid methyl half ester unsaturated dibasic acid half ester; dimethylmaleic acid, dimethyl fumaric acid unsaturated dibasic acid ester; acrylic acid, meta Α, β-unsaturated acids such as rillic acid, crotonic acid and cinnamic acid; α, β-unsaturated acid anhydrides such as crotonic acid anhydride and cinnamic acid anhydride, the α, β-unsaturated acid and lower fatty acids And monomers having a carboxyl group such as alkenylmalonic acid, alkenylglutaric acid, alkenyladipic acid, acid anhydrides and monoesters thereof.

  Further, acrylic acid or methacrylic acid esters such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate; 4- (1-hydroxy-1-methylbutyl) styrene, 4- (1-hydroxy-1) -Methylhexyl) Monomers having a hydroxy group such as styrene.

  In the toner of the present invention, the vinyl resin that can be used as the binder resin may have a crosslinked structure crosslinked with a crosslinking agent having two or more vinyl groups. The crosslinking agent used in this case is an aromatic resin. Examples of the group divinyl compound include divinylbenzene and divinylnaphthalene; Examples of the diacrylate compound linked with an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, and 1,4-butanediol diacrylate. 1,5-pentanediol acrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and those obtained by replacing acrylates of the above compounds with methacrylate; linked by an alkyl chain containing an ether bond Diacrylate compounds For example, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and the above compounds were replaced with methacrylate. Examples of the diacrylate compounds entangled with a chain containing an aromatic group and an ether bond include, for example, polyoxyethylene (2) -2,2-bis (4hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,2-bis (4hydroxyphenyl) propane diacrylate, and those obtained by replacing the acrylate of the above compound with methacrylate; For example, as over preparative compounds, trade name MANDA (Nippon Kayaku) is raised.

  Examples of the polyfunctional cross-linking agent include pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and those obtained by replacing the acrylate of the above compounds with methacrylate; And lucyanurate and triallyl trimellitate.

  These crosslinking agents can be used in an amount of 0.01 to 10 parts by mass (more preferably 0.03 to 5 parts by mass) with respect to 100 parts by mass of other monomer components.

  Among these crosslinkable monomers, those which are preferably used in the binder resin from the viewpoint of fixability and offset resistance are bonded with aromatic divinyl compounds (particularly divinylbenzene), chains containing aromatic groups and ether bonds. And diacrylate compounds.

  Examples of the polymerization initiator used in producing the vinyl resin include 2,2′-azobisisobutyronitrile and 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile). 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, 1,1′- Azobis (1-cyclohexanecarbonitrile), 2- (carbamoylazo) -isobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2-phenylazo-2,4-dimethyl-4-methoxy Valeronitrile, 2,2-azobis (2-methylpropane), methyl ethyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide Ketone peroxides such as oxide, 2,2-bis (tert-butylperoxy) butane, tert-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, di -Tert-butyl peroxide, tert-butyl cumyl peroxide, dicumyl peroxide, α, α'-bis (tert-butylperoxyisopropyl) benzene, isobutyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl Peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, m-trioyl peroxide, di-isopropyl peroxydicarbonate, di-2-ethylhexyl peroxy Carbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, dimethoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetylcyclohexylsulfonyl peroxide, tert-butyl peroxyacetate, tert-butylperoxyisobutyrate, tert-butylperoxyneodecanoate, tert-butylperoxy 2-ethylhexanoate, tert-butylperoxylaurate, tert-butylper Oxybenzoate, tert-butyl peroxyisopropyl carbonate, di-tert-butyl peroxyisophthalate, tert-butyl peroxyallyl carbonate, tert Amyl peroxy 2-ethyl hexanoate, di -tert- butyl peroxy hexahydro terephthalate, di -tert- butyl peroxy azelate and the like.

  Further, the binder resin has a peak molecular weight Mp of 5000 to 20000, a weight average molecular weight Mw of 5000 to 300,000, and a ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn by GPC of a tetrahydrofuran (THF) soluble component. Is preferably 5-50. When Mp and Mw are small and the distribution is sharp, a high temperature offset occurs. Further, when Mp and Mw are large and the distribution is broad, the desired low-temperature fixability cannot be obtained.

  The glass transition temperature of the binder resin is preferably 53 to 62 ° C. from the viewpoint of fixability and storage stability.

  In the toner of the present invention, the THF-insoluble content of the binder resin component when extracted for 16 hours is 15 to 50% by mass, preferably 15 to 45% by mass.

  Since the THF-insoluble component is an effective component for developing good releasability from a heating member such as a fixing roller, when applied to a high-speed machine, the amount of toner offset to the heating member such as a fixing roller is reduced. There is an effect to. When the amount is less than 15% by mass, the above effect is hardly exhibited. When the amount exceeds 50% by mass, not only the fixability is deteriorated but also the dispersibility of the raw materials in the toner is deteriorated and the chargeability is not uniform. Tend to be.

  Although the above resins may be used alone as the binder resin, two or more binder resins having different softening points may be mixed and used.

  In the present invention, a wax can be used as necessary to impart releasability to the toner. The wax has a low molecular weight because of ease of dispersion in the toner and high releasability. Hydrocarbon waxes such as polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax are preferably used, but one kind or two or more kinds of waxes may be used in a small amount as required. Examples include the following:

  Oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax, or block copolymers thereof; waxes based on fatty acid esters such as carnauba wax, sazol wax, and montanate wax; and deoxidation The fatty acid esters such as carnauba wax may be partially or wholly deoxidized. Furthermore, saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as pracidic acid, eleostearic acid, and valinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, and seryl alcohol Saturated alcohols such as melyl alcohol; long-chain alkyl alcohols; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; Saturated fatty acid bisamides such as acid amide, ethylene bislauric acid amide, hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N′-dioleyl Unsaturated fatty acid amides such as dipinamide, N, N-dioleyl sebacic acid amide; aromatic bisamides such as m-xylenebisstearic acid amide, N, N-distearylisophthalic acid amide; calcium stearate, laur Grafted with fatty acid metal salts such as calcium phosphate, zinc stearate, magnesium stearate (generally called metal soap), and aliphatic hydrocarbon waxes with vinyl monomers such as styrene and acrylic acid. Examples of waxes include partially esterified products of fatty acids such as behenic acid monoglyceride and polyhydric alcohols, and methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable oils and the like.

  Examples of the release agent particularly preferably used in the present invention include aliphatic hydrocarbon waxes. As such an aliphatic hydrocarbon wax, for example, a low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or a Ziegler catalyst under low pressure; Alkylene polymers obtained; synthetic hydrocarbon waxes obtained from the distillation residue of hydrocarbons obtained by the age method from synthesis gas containing carbon monoxide and hydrogen, and synthetic hydrocarbon waxes obtained by hydrogenating them; these aliphatics And hydrocarbon waxes separated by press sweating, solvent method, vacuum distillation and fractional crystallization.

  Examples of the hydrocarbon as the matrix of the aliphatic hydrocarbon wax include those synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (often a multi-component system of two or more types) (for example, Hydrocarbon compounds synthesized by the Gintor method and Hydrocol method (using a fluidized catalyst bed); Up to several hundred carbon atoms can be obtained by the Age method (using an identified catalyst bed) in which many waxy hydrocarbons are obtained Hydrocarbons; hydrocarbons obtained by polymerizing alkylene such as ethylene with a Ziegler catalyst. Among such hydrocarbons, in the present invention, it is preferable that the hydrocarbon is a linear hydrocarbon having a small number of branches and a long saturation, and particularly a hydrocarbon synthesized by a method not based on polymerization of alkylene has a molecular weight distribution. Is also preferable.

  Specific examples that can be used include Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries), high wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals), Sazol H1, H2, C80, C105, C77 (Schumann Sazol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP- 12 (Nippon Seiki Co., Ltd.), Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Petrolite Co., Ltd.), Kirou, Beeswax, rice wax, candelilla wax, carnauba wax (available at Celerica NODA Inc.) ) And the like.

  The timing of adding the release agent may be added at the time of melt-kneading during toner production or may be at the time of binder resin production, and is appropriately selected from existing methods. These release agents may be used alone or in combination.

  The release agent is preferably added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin. When the amount is less than 1 part by mass, the desired release effect cannot be obtained sufficiently. When the amount exceeds 20 parts by mass, the dispersion in the toner is poor, so that the toner adheres to the photoreceptor and the surface of the developing member / cleaning member is contaminated. And the like, and the toner image is likely to deteriorate.

  In the toner of the present invention, a charge control agent can be used to stabilize the chargeability. The charge control agent varies depending on the type and physical properties of other toner particle constituent materials, but generally 0.1 to 10 parts by mass per 100 parts by mass of the binder resin is preferably contained in the toner particles. It is more preferable that 1-5 mass parts is contained. As such a charge control agent, for example, an organometallic complex or a chelate compound is effective. Examples thereof include a monoazo metal complex; an acetylacetone metal complex; a metal complex or metal salt of an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid; Is mentioned. In addition, examples of the toner that controls the toner to be negatively charged include aromatic mono- and polycarboxylic acids and metal salts and anhydrides thereof; phenol derivatives such as esters and bisphenol;

  Specific examples that can be used include Spiron Black TRH, T-77, T-95 (Hodogaya Chemical Co., Ltd.), BONTRON (registered trademark) S-34, S-44, S-54, E-84, E- 88, E-89 (Orient Chemical Co., Ltd.), charge control resins can also be used, and the charge control agents described above can be used in combination.

  Other external additives may be added to the toner of the present invention as necessary. Examples thereof include resin fine particles and inorganic fine particles that function as a charging aid, a conductivity imparting agent, a fluidity imparting agent, an anti-caking agent, a release agent at the time of fixing with a heat roller, a lubricant, an abrasive, and the like.

  For example, examples of the lubricant include polyfluorinated ethylene powder, zinc stearate powder, polyvinylidene fluoride powder, and the like. Among these, polyvinylidene fluoride powder is preferable. Examples of the abrasive include cerium oxide powder, silicon carbide powder, and strontium titanate powder. These external additives can be sufficiently mixed using a mixer such as a Henschel mixer to obtain the toner of the present invention.

  In order to produce the toner of the present invention, binder resin, colorant, other additives, etc. are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill and then heat kneaded such as a heating roll, a kneader or an extruder. The toner of the present invention can be obtained by melt-kneading using a machine, pulverizing and classifying after cooling and solidification, and further mixing the desired additives as necessary with a mixer such as a Henschel mixer.

  For example, as a mixer, Henschel mixer (made by Mitsui Mining); Super mixer (made by Kawata); Ribocorn (made by Okawara Seisakusho); Nauter mixer, turbulizer, cyclomix (made by Hosokawa Micron); Spiral pin mixer (Manufactured by Taiheiyo Kiko Co., Ltd.); Ladige mixer (manufactured by Matsubo Co., Ltd.), and kneaders: KRC kneader (manufactured by Kurimoto Iron Works Co.); bus co kneader (manufactured by Buss); TEM type extruder (Manufactured by Toshiba Machine Co., Ltd.); TEX twin-screw kneader (manufactured by Nippon Steel Works); PCM kneader (manufactured by Ikegai Iron Works Co., Ltd.); three roll mill, mixing roll mill, kneader (manufactured by Inoue Seisakusho Co., Ltd.); Mining company); MS pressure kneader, Nider Ruder (Moriyama Seisakusho); Banbury mixer (Kobe Steel) As a pulverizer, a counter jet mill, a micron jet, an inomizer (manufactured by Hosokawa Micron); an IDS type mill, a PJM jet pulverizer (manufactured by Nippon Pneumatic Industry); a cross jet mill (manufactured by Kurimoto Iron Works); ULMAX (manufactured by Nisso Engineering Co., Ltd.); SK Jet O-Mill (manufactured by Seishin Enterprise Co., Ltd.); Kryptron (manufactured by Kawasaki Heavy Industries, Ltd.); Turbo Mill (manufactured by Turboe Industries Co., Ltd.); Examples of classifiers include: class seal, micron classifier, specick classifier (manufactured by Seishin Enterprise Co., Ltd.); turbo classifier (manufactured by Nissin Engineering Co., Ltd.); micron separator, turboplex (ATP), TSP separator (Hosokawa Micron) (Made by company) Elbow Jet (manufactured by Nippon Steel & Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Engineering Co., Ltd.); YM Micro Cut (manufactured by Yaskawa Shoji Co., Ltd.) can be mentioned. Ultrasonic (manufactured by Sakae Sangyo Co., Ltd.); Resonator Sheave, Gyroshifter (Tokuju Kosakusha Co., Ltd.); Vibrasonic System (manufactured by Dalton); Soniclean (manufactured by Shinto Kogyo Co., Ltd.); Turbo Screener (manufactured by Turboe Sangyo Co., Ltd.) Micro shifter (manufactured by Hadano Sangyo Co., Ltd.), circular vibrating sieve, etc.

  A method for measuring physical properties of the toner of the present invention is as follows. Examples described later are also based on this method.

(1) Measurement of molecular weight distribution by GPC A column is stabilized in a heat chamber at 40 ° C., THF is flowed through the column at this temperature as a solvent at a flow rate of 1 ml per minute, and about 100 μl of a THF sample solution is injected and measured. . In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value and the count value of a calibration curve prepared from several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK is suitably used. The detector uses an RI (refractive index) detector. In addition, it is preferable to combine a plurality of commercially available polystyrene gel columns as the column. of _{TSKgel G1000H (H XL), G2000H} (H XL), G3000H (H XL), G4000H (H XL), G5000H (H XL), G6000H (H XL), G7000H (H XL), include a combination of TSKgurd column be able to.

  Moreover, a sample is produced as follows.

  Place the sample in THF and let stand at 25 ° C. for several hours, then shake well and mix well with THF (until the sample is no longer united), and let stand for more than 12 hours. At that time, the standing time in THF is set to 24 hours. After that, a sample processed filter (pore size 0.2 to 0.5 μm, for example, Mysori Disc H-25-2 (manufactured by Tosoh Corporation) can be used) is used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

(2) Measurement of glass transition temperature of binder resin and toner Measuring device: differential scanning calorimeter (DSC), MDSC-2920 (manufactured by TA Instruments)
Measured according to ASTM D3418-82.

  The measurement sample is precisely weighed in an amount of 2 to 10 mg, preferably 3 mg. This is put into an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min at a temperature rise rate of 30 ° C. to 200 ° C. at normal temperature and humidity. The analysis is performed with a DSC curve in the temperature range of 30 to 200 ° C. obtained in the second temperature raising process.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. “Part” means “part by mass”.

(Manufacture of photoconductor)
<Photoreceptor (K1)>
The surface of the aluminum cylinder was honed and subjected to ultrasonic cleaning as a support.

  Next, an intermediate layer coating solution was prepared by dissolving 5 parts of N-methoxymethylated 6 nylon in 95 parts of methanol.

  This intermediate layer coating solution was dip-coated on a support and dried at 100 ° C. for 20 minutes to form an intermediate layer having a thickness of 0.6 μm.

  Next, an oxytitanium phthalocyanine crystal having a strong peak at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° with a Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction (charge generating substance) ) 3 parts, 3 parts of polyvinyl butyral resin (trade name: ESREC BM2, manufactured by Sekisui Chemical Co., Ltd.), and 35 parts of cyclohexanone were dispersed in a sand mill using glass beads having a diameter of 1 mm for 2 hours. A coating solution for charge generation layer was prepared by adding 60 parts of ethyl acetate.

  The charge generation layer coating solution was dip coated on the intermediate layer and dried at 50 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.2 μm.

で示される構造を有する正孔輸送性化合物６０部を、モノクロロベンゼン３０部／ジクロロメタン３０部の混合溶剤に溶解させることによって、電荷輸送層用塗布液を調製した。

A charge transport layer coating solution was prepared by dissolving 60 parts of a hole transporting compound having a structure represented by the formula (1) in a mixed solvent of 30 parts of monochlorobenzene / 30 parts of dichloromethane.

  This charge transport layer coating solution was dip coated on the charge generation layer.

  Next, the charge transport layer coating solution applied on the charge generation layer is irradiated with an electron beam in an atmosphere with an oxygen concentration of 10 ppm under the conditions of an acceleration voltage of 150 kV and an irradiation dose of 12 Mrad. A heat treatment was carried out for 10 minutes under the condition that the temperature of the body (= electron beam irradiated body) was 100 ° C. to form a charge transport layer having a thickness of 15 μm.

  Thus, an electrophotographic photosensitive member 1 having an intermediate layer, a charge generation layer, and a charge transport layer in this order on the support, and the charge transport layer being a surface layer was produced.

<Photoreceptor (K) 2>
In the same manner as in the electrophotographic photoreceptor 1, an intermediate layer and a charge generation layer were formed on the support.

  Next, the following formula

で示される構造を有するスチリル化合物１０部、および、下記式

10 parts of a styryl compound having the structure represented by the formula:

で示される繰り返し構造単位を有するポリカーボネート樹脂（粘度平均分子量（Ｍｖ）：２００００）１０部を、モノクロロベンゼン５０部／ジクロロメタン３０部の混合溶剤に溶解させることによって、第１電荷輸送層用塗布液を調製した。

10 parts of a polycarbonate resin (viscosity average molecular weight (Mv): 20000) having a repeating structural unit represented by the following formula is dissolved in a mixed solvent of 50 parts monochlorobenzene / 30 parts dichloromethane: Prepared.

  The first charge transport layer coating solution was dip coated on the charge generation layer and dried at 120 ° C. for 1 hour to form a first charge transport layer having a thickness of 20 μm.

  Next, a coating solution for the second charge transport layer is prepared by dissolving 60 parts of the hole transporting compound having the structure represented by the above formula (a1) in a mixed solvent of 50 parts of monochlorobenzene / 50 parts of dichloromethane. did.

  The coating solution for the second charge transport layer was spray-coated on the first charge transport layer.

  Next, the second charge transport layer coating liquid applied on the first charge transport layer is irradiated with an electron beam under an atmosphere having an oxygen concentration of 10 ppm under an acceleration voltage of 120 kV and an irradiation dose of 3 Mrad. Under the condition that the temperature of the electrophotographic photosensitive member (= electron beam irradiated body) was 100 ° C., a heat treatment was performed for 10 minutes to form a second charge transport layer having a thickness of 5 μm.

  In this manner, the electrophotographic photosensitive member 2 having the intermediate layer, the charge generation layer, the first charge transport layer, and the second charge transport layer in this order on the support, and the second charge transport layer being the surface layer. Produced.

<Photoreceptor (K) 3>
The hole transporting compound used for the charge transporting layer is changed from the hole transporting compound having the structure represented by the above formula (a1) to the following formula:

で示される構造を有する正孔輸送性化合物に変更した以外は、電子写真感光体１と同様にして電子写真感光体を作製し、これを電子写真感光体３とした。

An electrophotographic photosensitive member was produced in the same manner as the electrophotographic photosensitive member 1 except that the hole transporting compound having a structure represented by the formula (1) was changed to an electrophotographic photosensitive member 3.

<Photoreceptor (K) 4>
In the same manner as the electrophotographic photoreceptor 1, an intermediate layer, a charge generation layer, and a charge transport layer were formed on the support. Next, 100 parts of antimony-containing tin oxide fine particles having an average particle size of 0.02 μm (trade name: T-1, manufactured by Mitsubishi Materials Corporation), (3,3,3-trifluoropropyl) trimethoxysilane (Shin-Etsu Chemical) (Made by Co., Ltd.) 30 parts and a 95% ethanol-5% aqueous solution 300 parts mixed solution was dispersed in a milling device for 1 hour, the dispersed solution was filtered, washed with ethanol, dried, and 120 ° C. The surface of the antimony-containing tin oxide fine particles was treated by heating for 1 hour. Next, the following formula

で示される構造を有する硬化系アクリルモノマー（光重合性モノマー）２５部、２，２−ジメトキシ−２−フェニルアセトフェノン（光重合開始剤）５部、上記表面処理後のアンチモン含有酸化スズ微粒子５０部、および、エタノール３００部を、サンドミル装置で９６時間分散した後、これにポリテトラフルオロエチレン樹脂粒子（商品名：ルブロンＬ−２、ダイキン工業（株）製）２０部を加えて、さらにサンドミル装置で８時間分散することによって、保護層用塗布液を調製した。

25 parts of a curable acrylic monomer (photopolymerizable monomer) having a structure represented by the following: 5 parts of 2,2-dimethoxy-2-phenylacetophenone (photopolymerization initiator), 50 parts of antimony-containing tin oxide fine particles after the surface treatment 300 parts of ethanol was dispersed in a sand mill device for 96 hours, and then 20 parts of polytetrafluoroethylene resin particles (trade name: Lubron L-2, manufactured by Daikin Industries, Ltd.) were added thereto. For 8 hours to prepare a coating solution for the protective layer.

This protective layer coating solution is applied onto the charge transport layer by dip coating, dried at 50 ° C. for 10 minutes, and then irradiated with ultraviolet light having a light intensity of 1000 mW / cm ² for 40 seconds with a metal halide lamp, resulting in a film thickness of 3 μm. A protective layer was formed. In this way, an electrophotographic photoreceptor C4 having an intermediate layer, a charge generation layer, a charge transport layer, and a protective layer in this order on the support, and the protective layer being a surface layer was produced.

<Photoreceptor (K) 5>
An electrophotographic photosensitive member was produced in the same manner as the electrophotographic photosensitive member 1 except that the heat treatment after irradiating the coating solution for charge transport layer with an electron beam was not performed, and this was designated as an electrophotographic photosensitive member K5.

  Table 1 shows various physical properties of the photoreceptor.

<Example of production of binder resin A1>
Propoxylated bisphenol A (2.2 mol adduct): 25.0 mol%
Ethoxylated bisphenol A (2.2 mol adduct): 25.0 mol%
Terephthalic acid: 33.0 mol%
Trimellitic anhydride: 5 mol%
Adipic acid: 6.5 mol%
Acrylic acid: 3.5 mol%
Fumaric acid: 2.0 mol%
The polyester monomer is charged into a four-necked flask together with an esterification catalyst, and a decompression device, a water separation device, a nitrogen gas introduction device, a temperature measurement device, and a stirring device are attached and stirred at 135 ° C. in a nitrogen atmosphere. In the present production example, fumaric acid was added in portions at the early and late stages of the reaction in order to obtain a desired crosslinked structure in the present invention. A vinyl copolymer monomer (styrene: 84 mol% and 2 ethylhexyl acrylate: 14 mol%) and a mixture of 2 mol% of benzoyl peroxide as a polymerization initiator were added dropwise over 4 hours from the dropping funnel. Then, after reacting at 135 ° C. for 5 hours, the reaction temperature at the time of polycondensation was raised to 230 ° C. to carry out a condensation polymerization reaction. After completion of the reaction, the reaction product was taken out from the container, cooled and pulverized to obtain a binder resin 1.

  Various physical properties of the binder resin A1 are as shown in Table 2.

<Example of production of binder resin A2>
Terephthalic acid 31mol%
Trimellitic acid 7mol%
Propoxylated bisphenol A (2.2 mol adduct): 35 mol%
Ethoxylated bisphenol A (2.2 mol adduct): 27 mol%
The polyester monomer is charged into a four-necked flask together with an esterification catalyst, and a decompression device, a water separation device, a nitrogen gas introduction device, a temperature measurement device, and a stirring device are attached and stirred at 135 ° C. in a nitrogen atmosphere. A vinyl copolymer monomer (styrene: 84 mol% and 2 ethylhexyl acrylate: 14 mol%) and a mixture of 2 mol% of benzoyl peroxide as a polymerization initiator were added dropwise over 4 hours from the dropping funnel. Then, after reacting at 135 ° C. for 5 hours, the reaction temperature at the time of polycondensation was raised to 230 ° C. to carry out a condensation polymerization reaction. After completion of the reaction, it was taken out from the container, cooled and pulverized to obtain a binder resin A2. Various properties of the binder resin A2 are as shown in Table 2.

<Example of production of binder resin (BL)>
Into a four-necked flask, 300 parts of xylene is added, and the inside of the container is sufficiently replaced with nitrogen while stirring, and then heated to reflux.

  Under this reflux, a mixture of 76 parts of styrene, 24 parts of acrylate-n-butyl and 2 parts of di-tert-butyl peroxide was added dropwise over 4 hours, and then held for 2 hours to complete the polymerization. A polymer solution (5 L) was obtained.

<Example of production of binder resin (BH)>
Into a four-necked flask, 300 parts of xylene is added, and the inside of the container is sufficiently replaced with nitrogen while stirring, and then heated to reflux.

  Under this reflux, first, 73 parts of styrene, 27 parts of acrylic acid-n-butyl, 0.005 part of divinylbenzene and 2,2-bis (4,4-di-tert-butylperoxycyclohexyl) propane 0.8 Part of the mixture is added dropwise over 4 hours. After all was added dropwise, the polymerization was completed by maintaining for 2 hours to obtain a binder resin (5H) solution.

<Manufacture of binder resin B>
In a four-necked flask, 200 parts of a xylene solution of the low molecular weight component (5 L) (corresponding to 30 parts of the low molecular weight component) is added, and the temperature is raised and stirred under reflux. On the other hand, 200 parts of the high molecular weight component (5H) solution (equivalent to 70 parts of high molecular weight component) is put into another container and refluxed. After the low molecular weight component (5L) solution and the high molecular weight component (5H) solution were mixed under reflux, the organic solvent was distilled off, and the resulting resin was cooled, solidified, and pulverized to obtain a binder resin B. Various physical properties of the binder resin are as shown in Table 2.

<Example of production of binder resin C1>
Propoxylated bisphenol A (2.2 mol adduct): 46.8 mol%
Terephthalic acid: 34.8 mol%
Trimellitic anhydride: 11.8 mol%
Isophthalic acid: 5.6 mol%
Phenol novolac EO adduct: 1.0 mol%
Charge the above monomers together with an esterification catalyst into a 5 liter autoclave and attach a reflux condenser, moisture separator, N ₂ gas inlet tube, thermometer and stirrer at 230 ° C. while introducing N ₂ gas into the autoclave. A polycondensation reaction was performed. After completion of the reaction, it was taken out from the container, cooled and pulverized to obtain a binder resin C1. Various physical properties of this resin are as shown in Table 2.

<Example of production of binder resin C2>
Propoxylated bisphenol A (2.2 mol adduct): 47.1 mol%
Terephthalic acid: 49.9 mol%
Trimellitic anhydride: 3.0 mol%
Charge the above monomers together with an esterification catalyst into a 5 liter autoclave and attach a reflux condenser, moisture separator, N ₂ gas inlet tube, thermometer and stirrer at 230 ° C. while introducing N ₂ gas into the autoclave. A polycondensation reaction was performed. After completion of the reaction, it was taken out from the container, cooled and pulverized to obtain a binder resin C2. Various physical properties of this resin are as shown in Table 2.

<Production example of silica fine powder 1>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a metal silicon powder as a raw material is charged into the combustion flame with a hydrogen carrier gas having a pressure of 5 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 1 (M1). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 2>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a raw metal silicon powder is charged into the combustion flame with a hydrogen carrier gas having a pressure of 4 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 2 (M2). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 3>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a metal silicon powder as a raw material is charged into the combustion flame with a hydrogen carrier gas having a pressure of 11 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 3 (M3). Various physical properties of this fine silica powder are as shown in Table 3.

<Example of production of silica fine powder 4>
After adding 14 L of ethanol and 1.5 Kg of 28% aqueous ammonia solution to a 30 L glass reactor equipped with a stirrer, a dripping port, and a thermometer, ammonia gas was further blown to absorb 0.26 Kg and mixed to mix the ammonia mixture. Prepared. The mixed solution was adjusted to 10 ° C. ± 0.5 ° C. and stirred, so that a mixed solution of 1,130 g of tetraethoxysilane as a silane compound and 63 g of 3-aminopropyltriethoxysilane as a silane compound was adjusted to a temperature in the reaction vessel. While maintaining the temperature at 25 ° C., it was dropped and hydrolyzed to obtain a suspension of silica fine particles. Further, the fine particles were fired at 250 ° C. to obtain silica fine powder 4 (M4). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 5>
Water (2.18 L), methanol (7 L) and 28% aqueous ammonia solution (1.0 kg) were added to a 30 L glass reactor equipped with a stirrer, a dripping port and a thermometer to prepare an ammonia mixture. The mixed solution was prepared at 40 ° C. ± 0.5 ° C., and while stirring, a mixed solution of 912 g of tetramethoxysilane and 1.2 L of methanol was added dropwise while maintaining the temperature in the reaction vessel at 40 ° C. Hydrolysis was performed to obtain a suspension of silica fine particles. Further, the fine particles were fired at 250 ° C. to obtain silica fine powder 5 (M5). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 6>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a metal silicon powder as a raw material is charged into the combustion flame with a hydrogen carrier gas having a pressure of 1 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 6 (M6). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 7>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a metal silicon powder as a raw material is charged into the combustion flame with a hydrogen carrier gas having a pressure of 13 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 7 (M7). Various physical properties of this fine silica powder are as shown in Table 3.

<Example of production of silica fine powder 8>
A mixed gas having a volume ratio of argon and oxygen of 3: 1 is introduced into the reaction vessel to replace the atmosphere. Oxygen gas is supplied into this reaction vessel at 40 (m ³ / hr) and hydrogen gas at 20 (m ³ / hr), and an ignition device is used to form a combustion flame composed of oxygen-hydrogen. Next, a metal silicon powder as a raw material is charged into the combustion flame with a hydrogen carrier gas having a pressure of 0.5 kg / cm ³ to form a dust cloud. This dust cloud is ignited by a combustion flame and causes an oxidation reaction by dust explosion. After the oxidation reaction, the inside of the reaction vessel was cooled to obtain silica fine powder 8 (M8). Various physical properties of this fine silica powder are as shown in Table 3.

<Production example of silica fine powder 9>
After adding 14 L of ethanol and 1.5 Kg of 28% aqueous ammonia solution to a 30 L glass reactor equipped with a stirrer, a dripping port, and a thermometer, ammonia gas was further blown to absorb 0.26 Kg and mixed to mix the ammonia mixture. Prepared. The mixed solution was adjusted to 10 ° C. ± 0.5 ° C. and stirred, so that a mixed solution of 1,130 g of tetraethoxysilane as a silane compound and 63 g of 3-aminopropyltriethoxysilane as a silane compound was adjusted to a temperature in the reaction vessel. While maintaining the temperature at 45 ° C., it was dropped and hydrolyzed to obtain a suspension of silica fine particles. Further, the fine particles were fired at 250 ° C. to obtain silica fine powder 9 (M9). Various physical properties of this fine silica powder are as shown in Table 3.

[Cleaning blade settings]
(Cleaning blade setting 1)
As the cleaning blade, a blade made of urethane rubber having a thickness of 2.8 mm and a micro hardness of 65 degrees was used. The amount of penetration into the photoreceptor was set to 1.0 mm, and the contact angle with the photoreceptor was set to 30 degrees.

  Cleaning blade settings 2 to 4 were set as shown in Table 4.

[Example 1]
Binder resin A1 70 parts Binder resin A2 30 parts Magnetic iron oxide particles (average particle size 0.14 μm, Hc = 11.5 kA / m, σs = 90 Am ² / kg, σr = 16 Am ² / kg) 70 Part Fischer-Tropsch wax (melting point: 101 ° C.) 4 parts Charge control agent-3 2 parts The above materials were premixed with a Henschel mixer and then melt kneaded with a biaxial kneading extruder.

The obtained kneaded product is cooled, coarsely pulverized with a hammer mill, then pulverized with a turbo mill, and the finely pulverized powder obtained is classified using a multi-division classifier utilizing the Coanda effect. 9 μm toner particles were obtained. To 100 parts of toner particles, 1.0 part of hydrophobic silica fine powder S1 (BET 140 m ² / g, hydrophobized with 30 parts of hexamethyldisilazane (HMDS) and 10 parts of dimethyl silicone oil) and silica fine powder 1 0.2 part and 3.0 parts of strontium titanate were externally added and mixed, and sieved with a mesh having an opening of 150 μm to obtain toner 1 (T1).

(Evaluation method)
A commercially available LBP printer (Laser Jet 4345MFP, manufactured by HP) was modified to an A4 size of 50 sheets / minute (process speed 300 mm / sec), and the process cartridge shown in FIG. It was installed in the machine.

・ Cleaning blade chipping In a 34 ° C / 85% environment, toner is developed on the photoreceptor for 1 second every 30 seconds, and the time control of the back contrast is adjusted with the development bias to cancel the transfer. In this state, primary charge was applied, the mixture was idled for 2 hours, the entire region in the blade longitudinal direction was observed using a 500 × optical microscope, and evaluation was performed according to the following evaluation items. Evaluation was performed according to the following evaluation items.
A: The blade does not bend, and the blade after endurance is chipped and wear is less than 10 μm. B: The blade does not bend, but the endurance of the blade is not less than 10 μm. C: Only the both ends of the blade are wrinkled. No drowning D: Blade was drowned during evaluation

・ Concentration unevenness
Durability of 20,000 sheets of A4 horizontal paper with an image ratio of 10% in an environment of 32.5 ° C / 85%, leaving only the charging roller in an environment of 23 ° C / 5% for 24 hours, 23 ° C / 5% Under the environment, replace the photoconductor with an unused photoconductor, make the applied DC voltage of the halftone image and primary charge substantially the same as the DC voltage of development, and perform the halftone density without performing image exposure. An image (analog halftone) was imaged, and charging unevenness caused by an object that hinders normal charging of the photosensitive member, such as dirt on the charging roller and transfer residue, was evaluated according to the evaluation items.
A: With analog halftone, no streak or uneven charging failure occurred, and a uniform image was obtained.
B: A slight streak-like charging failure occurred in the analog halftone, and an image having no problem was obtained in a normal halftone image.
C: A streaky charge failure occurred in the analog halftone, and a slight streak charge failure occurred even in the normal halftone image.
D: A streaky or uneven charging failure occurred in the analog halftone, and a fogged image due to charging failure occurred in a normal halftone image or a solid white image.

-Drum scratches Endured 20,000 sheets of image ratio 2% A4 landscape paper in an environment of 15 ° C / 5%, and the applied DC voltage for solid black, halftone images, and primary charging is almost the same as the DC voltage for development. An image having a halftone density (analog halftone) was drawn without performing image exposure, and drum scratches were evaluated according to the following evaluation items.
A: Vertical streak image due to scratches is not generated. B: A vertical streak image due to scratches is slightly confirmed only with an analog halftone.
C: Slightly confirmed as solid black. Many are confirmed in the analog halftone.

・ Roller stain The state in which the toner is developed on the photoconductor in a 15 ° C / 5% environment for 1 second every 5 seconds, the time control of the back contrast is adjusted with the development bias, and the transfer is released. The primary charging is applied and the idle rotation is performed for 1 hour, and the charging AC current value of the charging roller is measured by applying a constant AC voltage before and after the idle rotation (if the toner slips through and the charging roller becomes dirty, the resistance increases and the charging current increases. In order to evaluate the amount of current decrease after idling, ranking was performed according to the following evaluation items.
A: Decreasing current of charging current after endurance is less than 0.05 mA B: Decreasing current of charging current after endurance is 0.05 or more and less than 0.10 mA C: Decreasing current of charging current after endurance is 0.10 mA or more and 0 Less than 3 mA D: Decrease current of charging current after durability is 0.3 mA or more

・ Fog The fog is measured using a reflection densitometer (reflectometer model TC-6DS manufactured by Tokyo Denshoku Co., Ltd.) before and after image formation. The worst reflection density after image formation is Ds. The reflection average density of the material was taken as Dr, Ds-Dr was determined, and this was evaluated as the fogging amount. Smaller numbers indicate less fog.

(Physical property measurement method)
・ BET
The specific surface area of the inorganic fine particles of the present invention is measured according to the BET method by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device “Gemini 2375 Ver. 5.0” (manufactured by Shimadzu Corporation). Was used to calculate the BET specific surface area (m ² / g).

[Examples 2-4 , Reference Examples 1-2, Examples 5-8 ]
Settings of photoconductor (K1-K5) described in Table 1, binder resin described in Table 2, silica fine powder (M1-M10) described in Table 3, and cleaning blade (C1-C4) described in Table 4 Indicates the value. Table 5 shows prescriptions of toner Nos. 2 to 10. In Examples 2 and 3, inorganic fine powder S2 (BET 245 m ² / g, hydrophobized with 20 parts of hexamethyldisilazane (HMDS)) was used.

  Table 6 shows the results of a similar test with the photoconductor, developer, and cleaning blade changed as in Example 1.

[Comparative Examples 1-6]
Developer Nos. 7 to 10 are prepared in the same manner as in Example 1 with the formulation described in Table 5, and the results of evaluation are performed after setting the photosensitive member, developer, and cleaning blade described in Table 6. In Comparative Examples 1, 5, and 7, the above S2 was used as the hydrophobic inorganic fine powder. In Comparative Example 6, titanium oxide (ST-10BS, manufactured by Teika Co., Ltd.) was used (see Table 3).

1 is a schematic view of a cartridge that is one embodiment of an image forming method of the present invention. FIG. It is explanatory drawing of the slip-through prevention layer formed in the contact part of a braid | blade and a photoreceptor. It is a figure which shows the outline of the output chart of Fisher scope H100V. It is a figure which shows an example of an output chart when the photoconductor used for this invention is made into a measuring object. It is explanatory drawing which shows an example of the roughening means which controls the surface shape of a photoreceptor. It is explanatory drawing which shows another example of the roughening means which controls the surface shape of a photoreceptor.

Explanation of symbols

1 Development roller (toner carrier)
2 Charging roller 3 Cleaning blade 6 Toner container 13 Photoconductor

Claims (5)

At least a step of charging the electrostatic charge image carrier with a charging member, an electrostatic latent image forming step of forming an electrostatic latent image on the charged electrostatic charge carrier, and a toner carried on the toner carrier. A developing step for visualizing the image by transferring it to an electrostatic latent image, a transferring step for transferring a toner image formed on the electrostatic image bearing member onto a recording medium, and a fixing step for heating and fixing the toner image on the recording medium. And an image forming method having a cleaning step of cleaning the surface of the electrostatic charge image carrier after transfer with a cleaning member,
The electrostatic image bearing member is a photosensitive member having a photosensitive layer and a protective layer on a support, and has a universal hardness value HU of 150 to 240 (N / mm ² ) on the surface of the photosensitive member, and an elastic property. The deformation ratio is 44% or more and 65% or less, and the cleaning member is a cleaning blade installed in contact with the electrostatic latent image bearing member,
The toner is a negatively chargeable magnetic toner having negatively chargeable magnetic toner particles containing at least a binder resin and magnetic iron oxide, and at least silica fine powder, and the silica fine powder has a volume-based median diameter (D50). There is 0.70～3.00Myuemu, Ri specific surface area of 1.0~10.0m ² / g der further 1/2 times or less the volume of the volume median diameter of powder the silica fine powder (D50) An image forming method, wherein a distribution integrated value is 0.5 to 20.0%, and a volume distribution integrated value having a double diameter or more is 0.5 to 20.0% . The protective layer of the electrostatic charge image carrier has a surface roughness Rz of 0.2 to 3.0 μm, a surface unevenness average interval Sm of 10 to 100 μm, and a surface sharpness Rku in the range of 3 <Rku <20. The image forming method according to claim 1, wherein: The image forming method according to claim 1 or 2 length from contact tip of the photosensitive member peripheral direction upstream and the cleaning blade to the blade top tip is characterized in that it is a 0.3 to 4 mm. The amount of penetration of the cleaning blade into the photoconductor is 0.2 to 2.0 mm, and the contact angle between the tangent at the tip of the contact portion upstream of the photoconductor and the cleaning blade is 10 °. the image forming method according to any one of claims 1 to 3, characterized in that it is to 40 °. Microhardness of the cleaning blade, the image forming method according to any one of claims 1 to 4, characterized in that at most 82 degrees 55 degrees.

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