JP2005266271A - Developing device, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form images of high quality without causing density unevenness for a long period of time by reducing a variation of the development gap "G" between a developer carrier and an image carrier in a development region. <P>SOLUTION: The developer carrier 35 in a roller shape is arranged opposite the image carrier 4 across a development gap "G" and carries a two-component developer consisting of a magnetic carrier and a toner, and the surface of the developer carrier 35 is made uneven to 5 to 20 μm surface roughness, the number of projections of 1 μm being ≤5 within a 0.2 mm measurement length. Consequently, abrasion of the surface of a developing sleeve 37 and surface abrasion of a magnetic carrier are reducible, variation of the development gap between the developer carrier 5 and image carrier 4 is reducible, and scooping performance for the two-component developer by the developer carrier 35 can be maintained, thereby maintaining stable developing performance. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a developing device, a process cartridge including the developing device, and an image forming apparatus.

  Conventionally, as an example of a developing device, a developing roller having a magnet having a plurality of fixed magnetic poles and a cylindrical developing sleeve surrounding the magnet is provided, and the developing sleeve has a constant developing gap between the outer peripheral surface and the outer peripheral surface of the photoreceptor. There is known a developing device in which the developing rollers are opposed to each other and are rotated around a center line.

  In such a developing device, the rising of the developer (however, a two-component developer having a magnetic carrier and toner) along the magnetic field lines of the magnetic field generated by the magnet occurs on the outer peripheral surface of the developing sleeve. In the spiked developer, charged toner adheres to the magnetic carrier related to the spike. Then, the toner in the spiked developer is transferred to the surface of the photoreceptor at a position facing the photoreceptor, so that the toner adheres to the electrostatic latent image formed on the surface of the photoreceptor and the toner image is formed. It is formed.

  The magnet is provided with a plurality of magnetic poles, and the magnets forming the respective magnetic poles are formed in a rod shape or the like, and in particular, the developing main magnetic pole for raising the developer is provided in the developing region portion of the developing sleeve surface. By rotating at least one of the developing sleeve and the magnet, the developer that is raised on the surface of the developing sleeve moves.

  The surface of the developing roller (developing sleeve) of an electrophotographic image forming apparatus such as a copying machine, printer, facsimile, etc., is subjected to roughing such as grooving or sandblasting unless the developing roller is of a type that rotates at low speed. It has been subjected. The reason for this is to prevent the developer from slipping and stagnating on the developing sleeve rotating at high speed, and to prevent the occurrence of a decrease in image density.

  7 and 8 show an example of the structure of the developing roller and the developing device. FIG. 7 is a schematic sectional view of the developing roller, and FIG. 8 is a schematic sectional view of the developing device. The developing roller 100 includes a cylindrical developing sleeve 102 and flanges 103 fixed to both ends thereof. Inside the developing sleeve 102 is provided a magnet 101 as a magnetic field generating means, and the developing roller 100 is supported so as to be rotatable around a center line. The developing roller 100 is disposed in the vicinity of the developer regulating blade 104 and the photoconductor 105. Such a developing roller and a developing device are disclosed in Patent Documents 1 and 2 and the like.

  Since the developing roller 100 is disposed in the vicinity of the developer regulating blade 104 and the photoconductor 105, if the developing sleeve 102 is shaken, the gap between the developer regulating blade 104 or the photoconductor 105 is changed to the developing sleeve. It will fluctuate at a rotation period of 102. As a result, unevenness in the amount of developer carried on the developing roller 100 and unevenness in developing ability occur, and as a result, the toner image formed on the photoconductor 105 exhibits density unevenness at a pitch corresponding to the shake of the developing sleeve 102. It will occur. Therefore, in order to obtain high image quality, it is necessary to increase the deflection accuracy of the developing sleeve 102.

JP-A-8-160736 JP 2000-10336 A

  The density unevenness described above occurs due to a change in the gap (development gap) between the developing sleeve 102 and the photosensitive member 105 or a speed change. Specifically, in the developing process, the toner in the two-component developer on the developing sleeve 102 is detached from the magnetic carrier and transferred onto the electrostatic latent image on the photoreceptor 105. At this time, it is desirable for the developing sleeve 102 to rotate at a constant speed while maintaining a constant developing gap with the photosensitive member 105, but the developing gap slightly fluctuates due to the influence of the shaking of the developing sleeve 102. This variation changes the amount of toner adhering to the electrostatic latent image formed on the photosensitive member 105 and causes density unevenness to appear.

  Particularly in recent years, the development gap tends to be narrowed as the image quality is improved. As the development gap becomes narrower, density unevenness due to fluctuations in the development gap or speed fluctuations becomes more prominent. Therefore, fluctuations in the development gap or speed fluctuations cannot be ignored.

  In the prior art, a method of cutting or grinding the developing sleeve 102 to improve runout accuracy and then performing sandblasting with a roughness of about 10 μm is also employed. However, the developing sleeve 102 subjected to sand blasting has a problem that the conveyance performance deteriorates with time, and it is difficult to maintain high image quality over a long period of time.

  In the developing sleeve 102 with the groove processed on the surface, there is no problem of deterioration in the pumping performance of the developer over time, but the deflection accuracy is likely to decrease due to stress during the groove processing, and the higher deflection accuracy than the sandblast product. There is a problem that it is difficult to obtain. Cutting and grinding may be performed after grooving, but burrs are generated in the groove during cutting and grinding, causing image defects due to detachment of burrs during continuous use, and reducing developer transport performance. There is a problem.

  In Patent Document 1, as a method for obtaining a highly accurate and highly durable developing roller, A configuration in which the surface of the developing sleeve has a number of ridge line protrusions having a polygonal shape, and fine irregularities are formed on portions other than the ridge line protrusions. 2. A configuration in which a conductive resin film, a metal treatment layer, etc. are provided on the developing sleeve to obtain irregularities. In this configuration, when it is used continuously, the toner adheres to the fine irregularities, causing problems such as a decrease in developing ability, and the processing process becomes complicated. Problems arise.

  In Patent Document 2, the surface roughness Rz of the developing sleeve is defined as 4 to 20 μm, and the average interval Sm between the peaks and depressions of the unevenness is defined as 30 to 80 μm, thereby preventing the wax component or the like from sticking to the developing sleeve surface. If possible, the irregularities defined by Rz and Sm described above cannot sufficiently achieve the purpose as will be described later.

  An object of the present invention is to reduce the variation in the development gap between the developer carrying member and the image carrying member in the development region, and to perform high-quality image formation without density unevenness over a long period of time.

  According to the first aspect of the present invention, there is provided a two-component development comprising a roller-shaped developer carrying member, which is opposed to the image carrying member with a development gap “G” and is rotatable about a center line, a magnetic carrier and toner. And a developing device that develops an electrostatic latent image formed on the image carrier with toner in a two-component developer carried on the developer carrier and conveyed to form a toner image In the above, irregular irregularities having a surface roughness of 5 to 20 μm are formed on the surface of the developer carrying member, and the height of 1 μm or more present in the measured length of 0.2 mm on the surface of the developer carrying member. The number of hills is 5 or less.

  According to a second aspect of the present invention, in the developing device according to the first aspect, the development gap “G” is 0.1 to 0.4 mm.

  A third aspect of the present invention is the developing apparatus according to the first or second aspect, wherein the magnetic carrier has a particle size of 20 to 50 μm.

  According to a fourth aspect of the present invention, in the developing device according to the third aspect, the magnetic carrier has a magnetic core material coated with a resin coat film, and the resin coat film crosslinks a thermoplastic resin and a melanin resin. The resin component and the charge control agent are contained.

  According to a fifth aspect of the present invention, there is provided a process cartridge according to a fifth aspect of the present invention, an image carrier having a toner image formed on an outer peripheral surface thereof, a cartridge case for rotatably holding the image carrier, and a cartridge case provided in the cartridge case. And a developing device according to any one of claims 1 to 4, disposed opposite to the outer peripheral surface of the body.

  According to a sixth aspect of the present invention, there is provided an image forming apparatus in which a toner image is formed on an outer peripheral surface, a charging device that uniformly charges the outer peripheral surface of the image carrier, and the uniformly charged 4. An optical writing device for writing an electrostatic latent image on the outer peripheral surface of the image carrier, and a toner image is formed by developing the electrostatic latent image written on the outer peripheral surface of the image carrier. And a transfer device that transfers the developed toner image to a recording medium.

  An image forming apparatus according to a seventh aspect of the present invention is provided in the apparatus main body, and is detachably disposed in the middle of the recording medium conveyance path from the recording medium accommodating section to the recording medium discharge section, and the recording medium conveyance path. And a process cartridge according to claim 5.

  According to the developing device of the first aspect of the present invention, it is possible to reduce the surface wear of the developer carrier and the surface wear of the magnetic carrier, and the development gap “G” between the developer carrier and the image carrier. Fluctuations can be reduced, stable developer pumping performance can be maintained over time, and stable development performance can be maintained.

  According to the developing device of the second aspect, it is possible to prevent the occurrence of non-uniform image density due to carrier adhesion to the image carrier and the electric field edge effect.

  According to the developing device of the third aspect of the invention, it is possible to prevent carrier adhesion to the image carrier and generation of nonuniform image density.

  According to the developing device of the fourth aspect of the invention, the magnetic carrier can be prevented from being scraped or spent.

  According to the process cartridge of the fifth aspect of the present invention, since the developing device according to any one of the first to fourth aspects is provided, the same effect as that of the first aspect of the present invention is achieved. Can do.

  According to the image forming apparatus of the sixth aspect of the invention, since the developing device according to any one of the first to fourth aspects is provided, it is possible to form an image with stable development performance.

  According to the image forming apparatus of the seventh aspect, since the process cartridge according to the fifth aspect is provided, the same effect as that of the fifth aspect can be obtained.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal front view schematically showing the entire structure of a color laser copying machine (hereinafter referred to as “copying machine”) as an image forming apparatus.

  A printer engine 3 for forming a color image is provided at the center of the apparatus main body 2 of the copying machine 1. The printer engine 3 includes a photoconductor 4 that is four image carriers that are spaced apart at equal intervals and arranged in parallel in a horizontal direction, a charging device 5 that uniformly charges the outer peripheral surface of the photoconductor 4, and a charging device. 5, an optical writing device 6 that forms an electrostatic latent image by exposing the outer peripheral surface of each photoconductor 4 charged according to image data, and supplying toner to the electrostatic latent image. A developing device 7 that visualizes the toner image as a toner image, an intermediate transfer belt 8 to which the toner image on the photoconductor 4 is sequentially transferred, and a toner remaining on the photoconductor 4 after the transfer of the toner image onto the intermediate transfer belt 8 The cleaning device 9 to be removed, the transfer device 10 for transferring the toner image transferred onto the intermediate transfer belt 8 to the recording medium S, and the like. In addition, toner images of different colors (Y: yellow, M: magenta, C: cyan, B: black) are formed on the four photoconductors 4, and the toner images of these colors are formed on the intermediate transfer belt 8. By being transferred, a color toner image is formed on the intermediate transfer belt 8, and the color toner image is transferred to the recording medium S.

  An upper part of the apparatus main body 2 has an ADF 11 that automatically feeds a document to be scanned, a contact glass 12 on which the document to be scanned is placed, and a document or contact glass 12 that is automatically fed by the ADF 11. An image reading device 13 for reading an image of the placed document is arranged.

  The image reading device 13 includes first and second traveling bodies 14 and 15 that can travel at a speed of 2: 1 parallel to the contact glass 12, a lens 16, a photoelectric conversion element (CCD) 17, and the like. The first traveling body 14 includes a light source 18 for illuminating a document placed on the contact glass 12 or a document conveyed by the ADF 11, and a first mirror 19 for reflecting light reflected by the document. Is installed. The second traveling body 15 is equipped with a second mirror 20 and a third mirror 21 that further reflect the light reflected by the first mirror 19. A lens 16 and a CCD 17 are arranged in front of the traveling direction of the light sequentially reflected by the first to third mirrors 19, 20, and 21.

  A plurality of stages of paper cassettes 24 for storing the recording medium S are provided at the lower part of the apparatus main body 2. The recording media S stored in these paper cassettes 24 are separated and fed one by one by a pickup roller 25, a feed roller 26, and a reverse roller 27, and the separated and fed recording media S are provided in the apparatus main body 2. The paper is transported along the paper transport path 28. On the paper conveyance path 28, a conveyance roller 29, a registration roller 30, a transfer device 10, a fixing device 31, a paper discharge roller 32, and the like are arranged.

  In such a configuration, the image forming operation by the copying machine 1 is performed as follows.

  First, an image of a document placed on the contact glass 12 or automatically fed by the ADF 11 is read by the image reading device 13. According to the read result, laser light corresponding to the image data of each color (yellow Y, magenta M, cyan C, black B) is emitted from the semiconductor laser of the optical writing device 6, and the laser light is integrated by the charging device 5. An electrostatic latent image is formed by exposing the outer peripheral surface of each photoreceptor 4 charged in this manner. By supplying toner of each color from each developing device 7 to the electrostatic latent image, the electrostatic latent image is visualized, and a toner image of each color is formed on the outer peripheral surface of the photoreceptor 4. The toner images on each photoconductor 4 are sequentially transferred onto an intermediate transfer belt 8 that moves in synchronization with the rotation of the photoconductor 4, and a color toner image is formed on the intermediate transfer belt 8.

  On the other hand, after the image reading by the image reading device 13 is started, the separation feeding of the recording medium S from the inside of the paper cassette 24 is started. The recording medium S separated and fed from the inside of the paper cassette 24 is transported on the paper transport path 28 and sent to a transfer position between the intermediate transfer belt 8 and the transfer device 10 by a registration roller 30 that is driven to rotate intermittently. .

  By feeding the recording medium S to the transfer position between the intermediate transfer belt 8 and the transfer device 10, the color toner image on the intermediate transfer belt 8 is transferred onto the recording medium S. The recording medium S to which the toner image is transferred is continuously conveyed on the paper conveyance path 28, and the toner image is fixed to the recording medium S in the process in which the recording medium S passes through the fixing device 31. The recording medium S on which the toner image is fixed is discharged onto a discharge tray 33 by a discharge roller 32.

  Under such a configuration, characteristic portions of the present embodiment will be described. FIG. 2 is a longitudinal front view showing the developing device 7. The developing device 7 includes a case 34 that houses a two-component developer having a magnetic carrier and toner, a developing roller 35 that is a developer carrier that is held by the case 34 and is driven to rotate about a center line. . The developing roller 35 is formed by a magnet 36 having a plurality of fixed magnetic poles and a cylindrical developing sleeve 37 surrounding the magnet 36.

  FIG. 3 shows a roughness profile of the outer peripheral surface of the developing sleeve. (A) and (b) are cases of the developing sleeve 37 of the present embodiment, and (c) is a case of the developing sleeve of the conventional example. In this embodiment, as compared with the conventional example, there are irregular changes on the whole irregularly, and the minute roughness is a measurement error level.

  In the case of such a roughness profile, the friction with the two-component developer for obtaining the conveying force of the two-component developer when incorporated in the developing device 7 is sufficiently obtained, and the fine roughness is small. In addition, the toner or components in the toner are prevented from sticking to the surface, and good image quality can be obtained over a long period of time.

  When such a roughness profile is to be regarded as a characteristic value, the standard defined by JIS or the like alone is not necessarily complete. Therefore, we decided to propose the number of peaks per unit length as a new characteristic value.

  In the JIS standard, Sm (average interval of unevenness) is defined as a characteristic value representing a peak pitch, but the meaning represents the interval between peaks relative to the average line of the roughness profile. It does not necessarily correspond to the number of mountains to indicate.

  The number of peaks per unit length (shown in claim 1 is 0.2 mm) shown in the present embodiment represents how many irregularities exist in the length. However, since too small irregularities do not affect, only the irregularities of 1.0 μm or more are counted.

  When the number of peaks is large, it means that the cross-sectional area of each peak is small, and when used continuously, the tip of the peaks tends to wear, and the transportability of the two-component developer decreases. In addition, since the friction with the surface portion of the magnetic carrier is increased, it is considered that the surface deterioration (coating layer) of the magnetic carrier is deteriorated. When the number of ridges is small, the surface of the developing sleeve 37 is less worn, and the contact with the magnetic carrier is almost surface contact, so that the surface layer of the magnetic carrier is less deteriorated. FIG. 4A is a schematic diagram showing a contact state between the developing sleeve 37 and the magnetic carrier A according to the present embodiment, and FIG. 4B shows a conventional example of the developing sleeve subjected to sandblasting and the magnetic carrier A. It is a schematic diagram which shows a contact state.

  Table 1 shows the results of measuring the pumping amount of the two-component developer using the developing roller (φ18.0) having the developing sleeve having the roughness profile shown in FIGS. 3 (a) to 3 (c). Show. The comparative example shown in Table 1 is the developing roller of the conventional example shown in FIG. 3C, Example 1 is the developing roller of the present embodiment shown in FIG. 3A, and Example 2 is FIG. This is a case where the developing roller of the present embodiment shown in FIG.

  As can be seen from Table 1, it can be seen that as the number of peaks increases, the rate of decrease in the pumping amount of the two-component developer tends to increase.

  The processing method of the roughness profile of the developing sleeve 37 is established by a method of causing the medium to collide with the surface of the blank tube as in the conventional blasting method. In particular, it is effective to use a cut wire having a relatively large shape (a metal wire cut into a short length).

  In the developing device 7, the development gap “G” between the outer peripheral surface of the developing sleeve 37 and the outer peripheral surface of the photoreceptor 4 and the particle size of the magnetic carrier greatly affect the image quality. When the developing gap “G” between the developing sleeve 37 and the photosensitive member 4 is 0.1 to 0.4 mm and the magnetic carrier particle size is 20 to 50 μm, the developing device 7 having the highest image quality and few side effects is obtained. .

  When the development gap “G” between the developing sleeve 37 and the photoconductor 4 is too small, the electric field between the developing sleeve 37 and the photoconductor 4 becomes too strong, and the magnetic carrier moves on the photoconductor 4. A problem called so-called carrier adhesion occurs. On the other hand, when the development gap “G” is too large, the development efficiency is reduced because the electric field is small, and the edge effect of the electric field is large at the edge of the image area, so that it is difficult to obtain a uniform image density. Become.

  If the particle size of the magnetic carrier is too small, the magnitude of the magnetization of each magnetic carrier is reduced, so that the magnetic binding force received from the developing roller 35 is weakened, and the carrier adheres to the photoreceptor 4. It becomes easy. When the particle size of the magnetic carrier is too large, the electric field between the magnetic carrier and the electrostatic latent image on the photoconductor 4 becomes sparse, making it difficult to obtain a uniform image density.

  The initial image level when an image is formed using a developing roller (φ18.0) having a developing sleeve having the roughness profile shown in FIGS. 3B and 3C, and the image level when continuously used Table 2 shows the test results. In Comparative Examples 1 and 2 shown in Table 2, when the conventional developing roller shown in FIG. 3C is used, Examples 1 to 3 are those of the present embodiment shown in FIG. This is a case where a developing roller is used.

  From the results shown in Table 2, it can be seen that when the developing roller having a small number of peaks is used, both the initial image level and the image level during continuous use are excellent.

  In addition, as a magnetic carrier of a two-component developer, a core material is coated with a resin coat film, and the resin coat film contains a resin component obtained by crosslinking a thermoplastic resin and a melanin resin, and a charge control agent. By using, the image level can be further improved.

  An example of the magnetic carrier in this case is shown in FIG. This magnetic carrier has a core material (ferrite) a, a resin coat film b surrounding the core material a, and large-diameter particles (such as alumina) c held by the resin coat film b. The resin coating film b is prepared by adding a charge adjusting agent to a resin component obtained by crosslinking a thermoplastic resin such as acrylic and a melamine resin, and absorbs an impact on the core material a, and the core material a is shaved. And the large particles c are held by a strong adhesive force. The diameter of the large particle c is set larger than the thickness of the resin coat film b. The large-diameter particles c have an effect of preventing the impact from other magnetic carriers on the resin coat film b and cleaning spent materials.

  In contrast to the conventional magnetic carrier that was developed based on the idea of obtaining a long life while gradually removing a hard coat film by using a two-component developer containing such a magnetic carrier, this implementation The magnetic carrier of this form absorbs the impact by the resin coat film b and suppresses the abrasion, and prevents the impact on the resin coat film b by the large-diameter particles c larger than the resin coat film b and cleans the spent object. By balancing it, it eliminates film scraping and spending and prolongs the service life, stabilizes the pumping amount of the two-component developer, that is, stabilizes the quality of the image formed using the two-component developer. Can be planned.

  A second embodiment of the present invention will be described with reference to FIG. In addition, the same part as the part demonstrated in FIG. 1 thru | or FIG. 5 is shown with the same code | symbol, and description is also abbreviate | omitted. A printer 40 that is an image forming apparatus according to the present embodiment includes a process cartridge 41 that includes the developing device 7 described in the above-described embodiment as one of the components.

  A process cartridge 41 is detachably attached to the printer 40 at a substantially central portion in an apparatus main body (not shown). In the apparatus main body, there are provided a paper cassette 24 that is a recording medium storage unit for storing the recording medium S, and a recording medium conveyance path 42 that extends from the paper cassette 24 to a paper discharge tray 33 that is a recording medium discharge unit. A process cartridge 41 is arranged in the middle of the conveyance path 42. A fixing device 31 is disposed on the downstream side of the process cartridge 49 along the conveyance direction of the recording medium S in the recording medium conveyance path 42.

  The process cartridge 41 includes a cartridge case 43, a photosensitive member 4 that is accommodated and held rotatably around the center line in the cartridge case 43, a charging device 5 that is accommodated in the cartridge case 43, a developing device 7, and a cleaning device 9. It is configured.

  In such a configuration, the image forming operation in the printer 40 provided with the process cartridge 41 is performed in the same manner as the image forming operation in the copying machine 1 of the first embodiment. The process cartridge 41 includes the developing device 7 including the developing roller 35 described in the first embodiment. Therefore, as in the first embodiment, the surface of the developing sleeve 37 is worn and magnetic. The surface wear of the carrier can be reduced, the fluctuation of the development gap between the developing sleeve 37 and the photosensitive member 4 can be reduced, the developer pumping performance stable over time can be maintained, and stable. Development performance can be maintained. Further, it is possible to prevent the occurrence of non-uniform image density due to carrier adhesion to the photoconductor 4 or the electric field edge effect, and to prevent the magnetic carrier from being scraped or spent.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional front view schematically showing the entire structure of a color laser copying machine according to a first embodiment of the present invention. It is a vertical front view which shows a developing device. 7 is a roughness profile of the outer peripheral surface of the developing sleeve between the present embodiment and a conventional example. It is a schematic diagram which shows the contact state of the developing sleeve and magnetic carrier in this Embodiment and a prior art example. It is sectional drawing which shows the structure of a magnetic carrier. It is a longitudinal front view which shows roughly the structure of the whole printer using the process cartridge which is the 2nd Embodiment of this invention. It is the schematic of the developing roller currently used with the image development apparatus of a prior art example. It is the schematic of the image development apparatus of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 4 Image carrier 5 Charging device 6 Optical writing device 7 Developing device 24 Recording medium accommodating part 33 Recording medium discharge | emission part 35 Developer carrier 41 Process cartridge 42 Recording medium conveyance path 43 Cartridge case a Core material b Resin coat film

Claims (7)

A roller-shaped developer carrier disposed opposite to the image carrier with a development gap “G” and rotatable about a center line; and a two-component developer comprising a magnetic carrier and a toner. In a developing device that forms a toner image by developing an electrostatic latent image formed on the image carrier with toner in a two-component developer carried and carried on an agent carrier.
Irregular irregularities having a surface roughness of 5 to 20 μm are formed on the surface of the developer carrying member,
The number of peaks having a height of 1 μm or more present in a measurement length of 0.2 mm on the surface of the developer carrying member is 5 or less.
A developing device.   2. The developing device according to claim 1, wherein the developing gap “G” is 0.1 to 0.4 mm.   The developing device according to claim 1, wherein the magnetic carrier has a particle size of 20 to 50 μm.   The magnetic carrier is characterized in that a magnetic core material is coated with a resin coat film, and the resin coat film contains a resin component obtained by crosslinking a thermoplastic resin and a melanin resin, and a charge control agent. The developing device according to claim 4. An image carrier on which a toner image is formed on the outer peripheral surface;
A cartridge case for rotatably holding the image carrier;
The developing device according to any one of claims 1 to 4, wherein the developing device is provided in the cartridge case and is disposed to face an outer peripheral surface of the image carrier.
A process cartridge comprising: An image carrier on which a toner image is formed on the outer peripheral surface;
A charging device for uniformly charging the outer peripheral surface of the photoreceptor;
An optical writing device for writing an electrostatic latent image on the outer peripheral surface of the uniformly charged image carrier;
The developing device according to any one of claims 1 to 4, wherein a toner image is formed by developing an electrostatic latent image written on an outer peripheral surface of the image carrier;
A transfer device for transferring the developed toner image to a recording medium;
An image forming apparatus comprising: A recording medium conveyance path provided in the apparatus main body and extending from the recording medium storage unit to the recording medium discharge unit;
The process cartridge according to claim 5, wherein the process cartridge is detachably disposed in the middle of the recording medium conveyance path;
An image forming apparatus comprising:

Images