JP4866585B2 - Lubricant coating apparatus, process cartridge having lubricant coating apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a lubricant application device that applies a lubricant to a member to be coated whose surface to be coated moves, a process cartridge having the lubricant application device, and an image forming apparatus.

  An image forming apparatus using an electrophotographic process includes a photoconductor as an image carrier, and charges the surface of the photoconductor by discharging to form an electrostatic latent image by exposing the charged photoconductor surface. A toner is supplied to the electrostatic latent image to make it visible, and the visible image formed on the surface of the photoreceptor is transferred onto the surface of the transfer paper, and then fixed and discharged. Since the untransferred toner remains on the surface of the photoconductor after the transfer of the visible image, the photoconductor surface is cleaned by a cleaning device so that they do not adversely affect the next image formation. Be prepared for the process. As a cleaning device, a cleaning blade made of an elastic material such as rubber or a cleaning brush in which synthetic resin fibers are formed in a brush shape is rubbed against the surface of the photosensitive member to remove deposits such as untransferred toner. Known.

  However, the cleaning blade and the cleaning brush as described above have a problem that if they are continuously rubbed with the photosensitive member, they are worn with time and the cleaning performance is deteriorated due to chipping or deformation. Further, since the surface of the photoconductor is also worn, the life is shortened. Therefore, in order to reduce the frictional resistance acting between the photoconductor and these cleaning members and to eliminate problems such as wear of the cleaning member and photoconductor, there is a method of applying a lubricant to the surface of the photoconductor. It has been taken. Also, if a lubricant is applied to the surface of the photoconductor, the coefficient of friction on the surface of the photoconductor decreases, so that a fluidizing agent or a charge control agent added to the toner is applied to the surface of the photoconductor by the contact pressure with the cleaning member. It is possible to prevent so-called filming that is fixed in a film form. The toner developed on the photoreceptor also has the advantage that transferability is improved by reducing the adhesive force with the surface of the photoreceptor.

  As means for applying a lubricant to the surface of the photoreceptor, for example, there are the following apparatuses. That is, a solid lubricant obtained by molding a lubricant such as a fatty acid metal salt into a rod shape is installed, and a brush roller is provided so as to contact both the solid lubricant and the photoreceptor. According to this application means, when the brush roller is driven to rotate, the solid lubricant is scraped by the rubbing of the brush roller to become powder and adheres to the brush fibers of the brush roller, and the powder adhered to the brush roller. A body-like lubricant is applied to the surface of the photoreceptor.

  By the way, in recent years, a demand for higher image quality has been increasing, and in order to realize particularly high-definition color image formation, toner particle diameters and spheroidization have been promoted. The reproducibility of dots is improved by reducing the particle size, and the developability and transferability can be improved by making the particles spherical. Since it is very difficult to produce such a small particle size and spherical toner by the conventional kneading and pulverization method, the polymerization produced by suspension polymerization method, emulsion polymerization method, dispersion polymerization method, etc. Toner is being adopted.

  However, when a toner having a spherical shape and a reduced particle size is used, there are some problems in cleaning on the photoreceptor after image formation. One of them is that it is difficult to clean a toner having a spherical shape and a small particle size by using a blade cleaning method generally used. The cleaning blade removes toner while rubbing the surface of the photoconductor, but the edge portion of the cleaning blade is deformed due to frictional resistance with the photoconductor, so that a minute space is generated between the photoconductor and the cleaning blade. The smaller the toner particle size, the easier it is to enter this space. Since the rolling friction force is smaller as the invading toner has a shape close to a spherical shape, it starts to roll in the space between the photosensitive member and the cleaning blade, passes through the cleaning blade, and leads to poor cleaning.

  As a measure for preventing such a cleaning failure, for example, a method of increasing the contact pressure of the cleaning blade to the photosensitive member is taken. As a result, the frictional force with the surface of the photoreceptor increases, and the cleaning blade is more easily damaged and worn. Further, blade squealing or blade turning caused by irregular vibration of the cleaning blade is likely to occur. Therefore, it has become more important to apply a lubricant uniformly to the surface of the photoreceptor to reduce the coefficient of friction on the surface of the photoreceptor.

  If the lubricant is not uniformly applied to the surface of the photoconductor, the coefficient of friction on the surface of the photoconductor becomes non-uniform, and the toner image is not transferred well. In addition, various abnormal images such as a so-called “image blur” inadequate toner adhesion in an image portion and a so-called “bokeh” blurred image occur.

  Here, since the toner remains on the surface of the photoreceptor after the toner image is transferred, it is necessary to clean the residual toner. The positional relationship on the member to be coated in the two steps of applying the lubricant after the transfer and cleaning the residual toner can be considered as the following two patterns. That is, there are two patterns, a relationship of cleaning after application where the lubricant is applied first and cleaning after, and a relationship of cleaning after application where the lubricant is applied after cleaning and the mechanism of abnormal image generation, respectively. Different.

First, the mechanism of abnormal image generation in the post-application cleaning pattern will be described.
In the case of this pattern, the lubricant is applied to the surface of the member to be coated in a state where the toner remains without being removed. Here, the portion corresponding to the character portion of the image originally carried on the surface of the coated member has a lot of residual toner on the surface of the coated member even after transfer to the transfer material, and the portion other than the character portion is substantially There is no residual toner. Since a large amount of residual toner is scraped off by the application brush and a cleaning blade at the cleaning position, the amount of lubricant on the surface of the applied member after passing through the cleaning position is increased. The application amount is uneven.

  In particular, when the same image is output continuously, the portion where the residual toner is large on the surface of the member to be coated is always the same, and thus such a bias becomes remarkable. Further, since residual toner adheres to an application member such as an application brush, the application brush becomes dirty, and it becomes difficult to continue to apply the lubricant uniformly over a long period of time. If a uniform lubricant layer cannot be formed on the surface of the coated member, the surface static friction coefficient μ may be biased or not low enough to transfer the toner, resulting in uneven transfer, and insects. Abnormal images such as biting, image blur, and blurring.

Next, the mechanism of abnormal image generation in the post-cleaning application pattern will be described.
If the application after cleaning is performed, the lubricant after application is not scraped off by the application brush and the cleaning blade, so that the above-described problems in the configuration of cleaning after application can be prevented. However, if the surface of the member to which the lubricant is applied enters the transfer position as it is and transfer is performed, an abnormal image may occur even though the surface static friction coefficient μ is within the appropriate range. I understood. This is because the lubricant particles are not fine enough to form a uniform layer just by being applied, and therefore the layer thickness is uneven on the surface of the member to be coated, which affects the transferability of the toner. If a uniform lubricant layer cannot be formed on the surface of the coated member, the static friction coefficient μ of the surface becomes non-uniform or does not become low enough to transfer toner, resulting in uneven transfer and insect erosion. An abnormal image such as image blurring or blurring.

JP 2000-206722 A JP 2001-305907 A JP-A-2005-070276

  Patent Documents 1 and 2 disclose a lubricant application device provided with an application member and a leveling member downstream of the cleaning device. However, the description of the requirements regarding the application member and the leveling member for further reducing the components downstream of the lubricant application device and the contamination in the machine has not been sufficient. In addition, there was no description corresponding to the removal of residual toner in the case of an image forming apparatus using polymerized toner having a spherical shape and a reduced particle size.

  In addition, Patent Document 3 does not describe a leveling member, and is insufficient as a condition for reducing contamination in the parts downstream of the lubricant application device and in the machine.

  SUMMARY OF THE INVENTION In view of the above-described conventional circumstances, the present invention provides a lubricant application device capable of reducing contamination on the downstream side of the lubricant application device and the machine, a process cartridge and an image forming apparatus with good image quality. It is aimed.

In order to achieve the above object, according to the present invention, a cleaning device for cleaning the surface of a rotating image carrier and a lubricant application unit for applying a lubricant to the surface of the image carrier are provided in a moving direction of the image carrier. The cleaning device and the lubricant application means are arranged in this order, and the lubricant application means rotates to apply an application roller for applying the lubricant to the surface of the image carrier, and a lubricant applied to the surface of the image carrier. A lubricant applying device, wherein the applying roller rotates in a direction that moves in a direction opposite to the moving direction of the surface of the image carrier in the applying portion. Proposed is a lubricant application device characterized in that the linear velocity is set slower than the linear velocity of the surface of the carrier.

The present invention is effective when the linear velocity ratio between the coating roller and the surface to be coated is approximately 1: 2.

  Further, the present invention is effective when the image carrier is a photoconductor.

Furthermore, the present invention is effective when the image carrier is an intermediate transfer member.
In order to achieve another object of the present invention, the present invention proposes a process cartridge comprising the lubricant application device according to any one of claims 1 to 4 .

In order to achieve another object of the present invention, the present invention proposes an image forming apparatus comprising the lubricant application device according to any one of claims 1 to 4 .
The present invention is effective when a polymerized toner is used as the developer.

  According to the configuration of the present invention, the lubricant can be reliably applied to the surface to be coated, and the pressure bonding / extension force of the lubricant is improved, so that contamination on the downstream side of the lubricant application device and in the machine can be reduced. . Therefore, it is possible to provide a process cartridge or an image forming apparatus having a long life and good image quality.

Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is an overall schematic diagram showing an embodiment of an image forming apparatus according to the present invention.
The image forming apparatus shown in FIG. 1 has an image forming unit 1 substantially at the center, a paper feeding unit 2 below the image forming unit 1, a reading unit 3 above the image forming unit 1, and an image forming unit 1 and a reading unit 3 4 is a color image forming apparatus having a configuration of the in-body discharge unit 4.

  In FIG. 1, an image forming unit 1 has a plurality of image carriers 5Y, 5C, 5M, and 5BK each composed of a drum-shaped photosensitive member. Each image carrier has toners of different colors. Each image is formed. In the illustrated example, yellow toner images, cyan toner images, and magenta toner images are formed on the surfaces of three image carriers 5Y, 5C, and 5M, and black toner is formed on the image carrier 5BK. An image is formed. The image carriers 5Y to 5BK are arranged in parallel with each other at a predetermined interval. An intermediate transfer member 6 is disposed opposite to the image carriers 5Y to 5BK, and a drum can be used as the intermediate transfer member 6. In the illustrated example, a plurality of support rollers 7, 8, 9 are used. An endless belt that is wound around and driven in the direction of arrow A is used.

  FIG. 2 is an explanatory diagram showing an enlarged main part of the image forming unit 1. The charging device 10 performs charging processing on the surface of the image carrier 5 around the image carrier 5. An exposure device 11 (shown in FIG. 1) that irradiates the body surface with laser light L, a developing device 12 that visualizes an electrostatic latent image formed on the surface of the image carrier 5 by exposure, and an intermediate transfer member 6 A transfer device 13 disposed opposite to the image carrier 5, a cleaning device 14 that removes and collects toner remaining on the surface of the photoreceptor after being transferred to the intermediate transfer member 6, and a friction coefficient on the surface of the image carrier 5. A lubricant application device 30 is provided.

  The charging device 10 includes a charging roller 10A as a charging member and a spring 10B as an urging member that presses the charging roller 10A to the image carrier 5 with a predetermined pressure. Although not shown, the charging roller 10A has a conductive elastic layer around a conductive shaft, and the conductive elastic layer and the photosensitive member (A1) are passed through the conductive shaft by a voltage application device (not shown). A predetermined voltage is applied to the gap between the photosensitive member and the surface of the photosensitive member to apply electric charges. Further, the developing device 12 sufficiently stirs the developer with the stirring screw 12A and magnetically adheres it to the developing roller 12B. The attached developer is thinned on the developing roller 12B by the developing doctor 12C, and the electrostatic latent image on the image carrier 5 is visualized by the developer. The transfer device 13 has a transfer bias roller, and electrically attaches the toner image on the image carrier 5 onto the intermediate transfer member 6 by the roller. The cleaning device 14 has a cleaning sheet made of urethane rubber or the like, and removes residual toner on the image carrier 5 by scraping with the sheet.

  In this embodiment, the image carrier 5, the charging device 10, the developing device 12, the cleaning device 14, and the lubricant applying device 20 are configured as a unitized process cartridge PC. The form of the process cartridge PC is arbitrary, but the process cartridge PC of the present invention is a combination of the lubricant applying device 20 and at least one component of the image carrier 5, the charging device 10, the developing device 12, and the cleaning device 14. It is.

  When image formation is started in the image forming apparatus, the image carrier 5 is rotated in the clockwise direction in FIG. 2, and at this time, the surface of the image carrier 5 is charged to a predetermined polarity by the charging device 10. Next, the charged surface is irradiated with laser light L based on image information from the exposure device 11 shown in FIG. 1, whereby an electrostatic latent image is formed on the image carrier 5. The image information is data sent from the computer or image data read by the reading unit 3. When the reading unit 3 is used, an original (not shown) placed on the contact glass 30 is reciprocated by a reading traveling body 31 including a document illumination light source and a mirror. The image information scanned in this way is read as an image signal into the CCD 33 installed behind the lens 32. The read image signal is digitized, image-processed, and written on the surface of the image carrier 5 by light emission of a laser diode (not shown) of the exposure device 11. The electrostatic latent image formed on the surface of the image carrier 5 is visualized as a toner image by the developing device 12. In the developing device 12, the electrostatic latent image is visualized by the dry developer carried on the developing roller 8.

  The above-described image forming operation is performed on all the image carriers 5, whereby yellow toner images, cyan toner images, magenta toner images, and black toner images respectively formed on the image carriers 5 Y to 5 BK are transferred to the intermediate transfer member 6. The images are sequentially transferred on top of each other. Further, in the image forming apparatus shown in FIG. 1, a secondary transfer device 15, which will be described in detail later, is disposed facing the support roller 7 with the intermediate transfer member 6 interposed therebetween.

  On the other hand, a recording medium P made of transfer paper, a resin film, or the like is sent out as indicated by an arrow B from a paper feeding unit 2 disposed below the image forming unit 1. The sheet is fed between the secondary transfer device 15 and the intermediate transfer body 6 at a predetermined timing by rotation. In this way, when the recording medium P passes through the secondary copying apparatus 15, the superimposed toner images on the intermediate transfer body 6 are collectively transferred onto the recording medium P by the action of the transfer apparatus 15. Then, after the toner image is fixed on the recording medium P by the fixing device 16, the toner image is discharged to the in-body discharge unit 4. Further, the transfer residual toner adhering to the surface of the intermediate transfer body 6 after the toner image transfer is removed by a belt cleaning device 16 which will be described in detail later.

  The image forming apparatus configured as described above includes a lubricant application device 20 that applies a lubricant to the image carrier 5, a lubricant application device 40 that applies a lubricant to the intermediate transfer body 6, and a secondary transfer device 15. And a lubricant applying device 50 for applying a lubricant to the transfer roller 15A.

  As shown in FIG. 2, the lubricant application device 20 that applies a lubricant to the image carrier 5 is disposed on the downstream side in the moving direction of the image carrier 5 of the cleaning device 14 that removes residual toner on the image carrier 5. It is disposed in a housing integral with the cleaning device 14. The lubricant application device 20 includes a lubricant application member 21 formed in a roller shape by winding a brush around a metal shaft. The lubricant application member 21 rotates to come into sliding contact with the solid lubricant 22 and the image carrier. The solid lubricant 22 is urged so as to come into contact with the lubricant application member 21 by an urging member 24 made of a spring or the like. By rotating the lubricant application member 21, the solid lubricant 22 is finely powdered. It is scraped off and applied to the surface of the image carrier 5. At this time, the lubricant application member 21 is rotated in the same direction as the image carrier 5. Therefore, the lubricant application member 21 moves in the opposite direction to the image carrier 5 at the contact point between the lubricant application member 21 and the image carrier 5. The lubricant applied to the image carrier 5 is pressure-bonded and extended on the surface of the image carrier 5 by the leveling member 23.

  By the way, the state in which the lubricant is applied on the image carrier 5 is roughly divided into two, one is a state in which the particles are still on the particle carrier, and the other is a thin and strong coating on the image carrier 5. It is in the state. The ideal is the latter state that contributes to the protection of the image carrier, and the former state is likely to float, causing in-machine contamination.

  As shown in FIG. 5, the conventional lubricant application device 120 is provided immediately after the moving direction cleaning device 112 of the image carrier 105 as in the present invention. Different from the invention. That is, in the conventional lubricant application device 120, the lubricant application roller 121 moves in the forward direction with the image carrier 5 at the contact point between the lubricant application roller 121 and the image carrier 5. Compared with the configuration of the present invention, this conventional configuration has a low pressure bonding / extension efficiency of the lubricant 122 by the application roller 121 around which the brush is wound. Therefore, in order to sufficiently protect the image carrier 105, the lubricant is correspondingly increased. It was necessary to increase the absolute coating amount of 122. However, application of an excessive amount of lubricant tends to cause contamination of other parts (particularly the charging roller) and causes problems such as abnormal images. Therefore, the linear pressure of the leveling member 123 is increased and the excess lubricant 122 is removed. It was necessary to stop it. The linear pressure of the leveling member 123 also acts on the pressure bonding / extension of the lubricant 122, but mainly acts as a blocking force for the excessive lubricant 122.

  On the other hand, the lubricant application device 20 of the present invention rotates the direction of rotation of the lubricant application member 21 around which the brush is wound in the reverse direction, that is, in the same direction as the image carrier 5. For this reason, the lubricant is applied as if it is applied to the image carrier 5, and the pressure bonding / extension efficiency of the lubricant by the brush is improved. For this reason, the image carrier 5 can be sufficiently protected with a small amount of coating, and the linear pressure of the leveling member 23 can be lowered. Improvement in the pressure-bonding / extension efficiency of the lubricant by the lubricant application member 21 around which the brush is wound also leads to stabilization of the formation of the photosensitive member protective layer. As a result, the image quality is also improved. Furthermore, contamination of the member on the downstream side of the application position, for example, the charging roller 10 can be reduced. It has been found that this effect can be further enhanced by setting the lubricant application member 21 to a linear velocity slower than the linear velocity of the image carrier 5. The reason for this is not clarified, but if the linear velocity of the lubricant application member 21 is slower than the linear velocity of the image carrier 5, it is considered that the application force of the lubricant to the image carrier 5 is enhanced.

  By the way, the rotation direction of the lubricant application member 21 around which the brush is wound, the amount of lubricant applied, and the linear pressure of the leveling member 23 need to be balanced, and the lubricant application member 21 around which the brush of the present invention is wound is important. Even if the linear pressure of the leveling member 23 is the same as that of the prior art, the blocking force of the leveling member 23 is too strong, and the coated lubricant is peeled off, causing filming. End up.

Therefore, when the linear pressures of the leveling members 23 and 123 of the lubricant coating device 20 of the present invention and the conventional lubricant coating device 120 shown in FIG. 5 were examined, there was a difference as shown in Table 1.

  In this table, ◎ indicates that the crimping / extension is excellent, ○ indicates good, Δ indicates acceptable, and × indicates impossibility. As apparent from Table 1, the present invention can be used in the range of 0.10 to 0.40 (N / cm), and among them, 0.25 to 0.35 (N / cm) is most preferable. . The conventional apparatus is used in the range of 0.45 to 0.65 (N / cm), which is higher than that of the present invention.

  In the present embodiment, since the linear pressure of the leveling member 23 can be made small, the leveling member 23 can be brought into contact with the image carrier 5 by a trailing method to improve the balance with the lubricant application amount. it can. Further, in this embodiment, even if an image quality factory using polymerized toner as a developer is attempted, defective cleaning can be prevented by applying a uniform pressure-bonded / extended lubricant.

FIG. 3 is a view showing a lubricant application device 40 for applying a lubricant to the intermediate transfer member 6.
The lubricant application device 40 is disposed in a housing integral with the cleaning device 16 on the downstream side in the moving direction of the intermediate transfer member 6 of the cleaning device 16 that removes residual toner on the intermediate transfer member 6. The solid lubricant 42 of the lubricant application device 40 is urged at a predetermined pressure to the lubricant application member 41 made of a brush roller by an urging member 44 made of a spring or the like. The solid lubricant 42 is scraped off by the rotation of the lubricant application member 41 and applied to the surface of the intermediate transfer member 6. The powder lubricant applied to the surface of the intermediate transfer member 6 is pressed and extended onto the surface of the intermediate transfer member by the leveling member 43. Also in this lubricant application device 40, the rotation direction of the intermediate transfer body 6 and the rotation direction of the lubricant application member 41 composed of brush rollers are the same direction, and at the contact point between the lubricant application member 41 and the intermediate transfer body 6. The lubricant application member 41 and the intermediate transfer member 6 move in directions opposite to each other.

FIG. 4 is a view showing a lubricant application device 50 for applying a lubricant to the transfer roller 15A of the secondary transfer device 15.
The lubricant application device 50 is provided in a cartridge in which a transfer roller 15A and a surface of the transfer roller 15A are integrally provided with a cleaning device 15B. The solid lubricant 52 of the lubricant application device 50 is urged at a predetermined pressure to the lubricant application member 51 formed of a brush roller by an urging member 54 formed of a spring or the like. The solid lubricant 52 is scraped off by the rotation of the lubricant application member 51 and applied to the surface of the transfer roller 15A. The powder lubricant applied to the surface of the transfer roller 15A is pressure-bonded and extended onto the surface of the intermediate transfer member by the leveling member 43. Also in this lubricant application device 50, the rotation direction of the transfer roller 15A is the same as the rotation direction of the lubricant application member 51 composed of a brush roller, and the lubricant is at the contact point between the lubricant application member 51 and the transfer roller 15A. The application member 41 and the intermediate transfer member 6 move in the opposite directions.

  Next, according to the present invention, Experiments 1, 2, 3, and 4 were performed on the lubricant application device. Experiments 1, 2, and 4 are experiments using the lubricant application apparatus 20 of the process cartridge PC shown in FIG. 2, and Experiment 3 is an experiment using the lubricant application apparatus 40 of FIG.

  In Experiment 1, the cleaning sheet of the cleaning device 14 is a urethane rubber sheet having a thickness of 2 mm manufactured by Bando Chemical Co., Ltd., and the contact pressure is 20 ± 10 (g / cm) against the image carrier 5. Installed so that the angle is 75 ± 10 (°), and the lubricant application member 21 uses a brush roller of a conductive nylon brush with a hair length of 3 mm manufactured by Toei Sangyo Co., Ltd., and bites into the image carrier 5. The sheet leveling member 23 is a urethane rubber sheet having a thickness of 1.5 mm manufactured by Toyo Tire & Rubber Co., Ltd., with a contact angle of 15 ± 5 (°), a contact line. The pressure is 0.30 (N / cm), the charging roller 7 is a rubber roller having an outer diameter of 14 mm manufactured by Hokushin Kogyo Co., Ltd., and two process cartridges PC are installed so as to be rotated with respect to the image carrier 5. Prepared. One is made so that the brush roller rotates in the same direction as the rotation direction of the image carrier 5, and the other is made so that the brush roller rotates in the opposite direction to the rotation direction of the image carrier 5. did.

  These process cartridges PC were put into Imagio NeoC325 manufactured by Ricoh Co., Ltd., and under a laboratory environment, 1000 sheets of continuous paper were passed under the condition of A4 size lateral paper, and the contamination of the charging roller was evaluated. In order to efficiently evaluate the contamination of the charging roller, the charging roller cleaner was not used and the image area of the paper passing image was set to 25%. In image evaluation, a halftone image with high detection capability was output in a low-temperature and low-humidity environment, and judged based on the presence or absence of an abnormal image.

  As a result of Experiment 1, an abnormal image due to contamination of the charging roller was confirmed in the unit in which the rotation direction of the brush roller was opposite to that of the image carrier 5, and was not confirmed in the unit in the same direction.

  In Experiment 2, two process cartridges were prepared under the same conditions as in Experiment 1, one with a sheet-like leveling member attached, and the other with a leveling member removed. The rotating direction of the coating member was the same as that of the photoreceptor.

  As described above, these process cartridges were put into Imagio NeoC325 manufactured by Ricoh Co., Ltd., and 1000 sheets of continuous paper were passed under the conditions of A4 size horizontal paper in a laboratory environment to evaluate the contamination of the charging roller. . In order to efficiently evaluate the contamination of the charging roller, the charging roller cleaner was not used and the image area of the paper passing image was set to 25%. In image evaluation, a halftone image with high detection capability was output in a low-temperature and low-humidity environment, and judged based on the presence or absence of an abnormal image.

As a result of Experiment 2, an abnormal image due to charging roller contamination was confirmed in the unit without the leveling member, and not confirmed in the unit with the leveling member.
In Experiment 3, a urethane rubber sheet having a thickness of 2 mm manufactured by Hokushin Kogyo Co., Ltd. was used as the cleaning sheet of the cleaning device 16, and the contact pressure was 25 ± 10 (g / cm) with respect to the image intermediate transfer body 6 and the contact angle. The lubricant application member 41 is a brush roller of an insulating polyester brush having a hair foot length of 3 mm manufactured by Ashiya Co., Ltd., and the amount of biting into the intermediate transfer member 6 is 1 mm. For the sheet-shaped leveling member 43, a urethane rubber sheet having a thickness of 1.0 mm manufactured by Toyo Tire & Rubber Co., Ltd. is used, the contact angle is 25 ± 5 (°), and the contact linear pressure is 0. Two intermediate transfer devices installed at .30 (N / cm) were prepared, one was prepared so that the rotation direction of the coating brush was the same as the rotation direction of the intermediate transfer belt, and the other was the reverse direction.

  These intermediate transfer devices were put into an ImagioColor 5100 manufactured by Ricoh Co., Ltd., and under a laboratory environment, 10,000 sheets were continuously passed under the condition of A4 size paper, and the transferability was evaluated. Ricoh's original evaluation image was used as the paper passing image, and the presence or absence of an abnormal image was judged in the process of passing 10,000 sheets.

As a result of Experiment 3, an abnormal image was confirmed in a unit in which the rotation direction of the brush was opposite to that of the transfer belt, but not in a unit in the same direction.
In Experiment 4, two process cartridges including a cleaning sheet, a coating brush, a leveling member, and a charging roller having the same conditions as in Experiment 1 were prepared. In either case, the rotation direction of the brush is the same as that of the photoconductor, but the linear velocity ratio between the application brush and the photoconductor is 1: 1 and the other is 1: 2.

  As in Example 1, these process cartridges were loaded into Imagio NeoC325 manufactured by Ricoh Co., Ltd., and in a laboratory environment, 1000 sheets of continuous paper were passed under the conditions of A4 size lateral paper, and the charging roller was evaluated for dirt. went. In order to efficiently evaluate the contamination of the charging roller, the charging roller cleaner was not used and the image area of the paper passing image was set to 50%. In image evaluation, a halftone image with high detection capability was output in a low-temperature and low-humidity environment, and judged based on the presence or absence of an abnormal image.

  As a result of Experiment 4, an abnormal image due to the charging roller was confirmed in a unit with a linear velocity ratio of 1: 1, but such an abnormal image was not confirmed at a linear velocity ratio of 1: 2.

1 is a schematic explanatory diagram showing an outline of an image forming apparatus according to the present invention. It is explanatory drawing which expands and shows the image formation part of this invention. It is explanatory drawing which shows the leaning apparatus of the intermediate transfer body of this invention. It is explanatory drawing which shows the secondary transfer apparatus of this invention. It is explanatory drawing which shows the conventional lubricant application apparatus.

Explanation of symbols

5 Image carrier 6 Intermediate transfer member 14 Cleaning device 15 Secondary transfer device 16 Intermediate transfer member cleaning device 20, 40, 50 Lubricant coating device 21, 41, 51 Lubricant coating member 22, 42, 52 Lubricant 23, 43,53 Leveling member

Claims (7)

A cleaning device for cleaning the surface of the rotating image carrier, and a lubricant application unit for applying a lubricant to the surface of the image carrier, in the order of the cleaning device and the lubricant application unit in the moving direction of the image carrier. Arranged,
The lubricant applying means comprises a coating roller for applying the lubricant to rotate on the surface of the image bearing member, and a leveling member for crimping, extending the lubricant applied to the surface of the image carrier,
In the lubricant application device in which the application roller rotates in a direction moving in a direction opposite to the moving direction of the surface of the image carrier in the application unit,
The lubricant application device, wherein the application roller is set to a linear velocity slower than a linear velocity of the surface of the image carrier. 2. The lubricant application device according to claim 1 , wherein a linear velocity ratio between the application roller and the surface of the image carrier is approximately 1: 2. 3. The lubricant application device according to claim 1, wherein the image carrier is a photoconductor. 3. The lubricant application device according to claim 1, wherein the image carrier is an intermediate transfer member. 5. A process cartridge comprising the lubricant application device according to claim 1 . An image forming apparatus comprising the lubricant application device according to claim 1 . 7. The image forming apparatus according to claim 6 , wherein a polymerized toner is used as the developer.

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