JP2012022213A - Cleaner and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily maintain the ability to clean using a cleaning action of a cleaning roller 104 with a simple configuration in a long period.SOLUTION: A surface of a cleaning roller 104 having a large number of raised brush pieces 104b provided radially in a circumferential direction is constituted by a brush bristle area formed from leading end portions of the raised brush pieces 104b, and a porous area in the brush bristle area formed from an elastic porous member 104c adjacent to the brush bristle area in the circumferential direction. Even if the state of the contact of the cleaning roller 104 with a surface of a body 103 to be cleaned changes in a certain degree, a function of removal of adhering matter E is maintained satisfactorily by a scraping action due to a slide friction of the porous area against the adhering matter E adhering to the surface of the body 104 to be cleaned and the recovery action of the brush bristle area.

Description

  The present invention relates to a cleaning apparatus and an image forming apparatus that include a cleaning roller that removes deposits attached to an object to be cleaned.

  In general, a cleaning device provided with a rotating brush-like cleaning roller in various devices has been widely used in machines and devices in various technical fields. For example, in various image forming apparatuses such as copiers, facsimiles, and printers, a photosensitive drum (image carrier), a charging roller that charges the photosensitive drum, or a member to be cleaned such as a transfer belt such as an intermediate transfer member. A cleaning device that cleans the surface with a cleaning roller (brush roller) is used.

  In recent years, in order to extend the life of the cleaning capability, the cleaning devices in recent years have the tips of numerous brushed brush pieces arranged radially along the circumferential direction of the cleaning roller on the surface of the object to be cleaned. A structure is being used that removes deposits adhering to the surface of the object to be cleaned by rotating while rubbing. As this type of cleaning device, a cleaning roller is driven to rotate by a driving device to scrape off deposits adhering to the surface of the object to be cleaned while maintaining a predetermined speed (see Patent Document 1). In addition, an elastic layer is provided between the shaft of the cleaning roller and a brushed brush piece covering the outer periphery of the cleaning roller so as to have a simple configuration, and the driven roller rotates in contact with the surface of the rotating object to be cleaned by its own weight or light pressure. The thing of the structure which does not provide the rotational drive mechanism made to clean by this is also proposed (refer patent document 2).

Japanese Patent Laid-Open No. 07-140763 JP 2005-352335 A

  However, these conventional cleaning devices have a problem that it is difficult to maintain the cleaning ability of the cleaning roller over a long period of time while having a simple and inexpensive configuration. That is, according to the cleaning device described in Patent Document 1 described above, not only a driving device for driving the cleaning roller is required, but also in order to suppress plastic deformation of the brush fiber, which is generally called brush fall, It is necessary to provide a means for regulating the amount of brush biting of the cleaning roller with respect to the object to be cleaned. As a result, the structure of the cleaning device tends to be complicated and expensive. The amount of brush biting referred to here is the number of brushed brush pieces in the radial direction of the cleaning roller when the tips of the many brushed brush pieces provided on the cleaning roller are brought into pressure contact with the surface of the object to be cleaned. Refers to the maximum amount of deformation.

  On the other hand, if a cleaning roller with a short hair length, which has been increasing in recent years, is used, a driving device for driving the cleaning roller becomes unnecessary, and there is a possibility that means for regulating the amount of brush bite can be omitted. However, since the contact pressure must be set relatively low in order to suppress elastic deformation of the brushed brush piece, the nip width in the rotational direction between the cleaning roller and the object to be cleaned becomes narrow, and the object to be cleaned There is a tendency that the contact pressure to the cleaning roller is not kept constant. For this reason, the adhered matter on the object to be cleaned may not be able to be removed uniformly, and the required cleaning ability is the scraping action on the object adhered to the surface of the object to be cleaned, and the scraped attachment. There is a problem that it is difficult to maintain the recovery of the kimono for a long period of time.

  Furthermore, in the apparatus described in Patent Document 2 described above, a proposal has been made to provide an elastic layer on the cleaning roller. However, since it is difficult to maintain elasticity over a long period of time, it becomes impossible to maintain a good cleaning capability, After the period of use, streaky marks may remain on the surface of the object to be cleaned, leading to image defects and the like.

  The present invention has been made in such a background, and an object thereof is to improve the cleaning ability of the cleaning roller over a long period of time with a simple configuration in an image forming apparatus using an electrostatic transfer process. An object of the present invention is to provide a cleaning device and an image forming apparatus that can be maintained.

  In order to achieve the above object, in the present invention, the cleaning roller supported by the rotating shaft rubs the surface of the rotating object to be cleaned to remove the deposits on the surface of the object to be cleaned. In the configured cleaning device, the outer peripheral surface of the cleaning roller is formed in a brush bristle region composed of a brushed brush piece configured to alternately form regions in the circumferential direction of the cleaning roller, and the brush bristle region It is composed of a porous region made of an elastic porous member arranged adjacent to the surface, and at least the porous region is rubbed against the surface of the object to be cleaned.

  According to such a configuration, when the cleaning roller rotates, the porous region and the brush bristle region alternately come to the surface of the object to be cleaned, and the contact state of the cleaning roller with respect to the surface of the object to be cleaned is to some extent. Even if it changes, the removal function of the adhering matter is maintained well by the uniform rubbing action by the rubbing of the porous area to the adhering substance adhering to the surface of the object to be cleaned and the recovery action by the brush bristle area. It has come to be.

  In the present invention, it is desirable that an outer diameter of the brush bristle region of the cleaning roller is set to be smaller than an outer diameter of the porous region.

  According to such a configuration, the positioning of the cleaning roller with respect to the object to be cleaned is maintained constant by the porous region, so that the so-called brush collapse of the tip of the brushed brush piece is prevented, and the object to be cleaned is The function of removing deposits is well maintained by the uniform scraping action by rubbing of the porous region and the collecting action by the brush bristle region on the deposit adhering to the surface.

  In the present invention, the bristle region and the porous region may be configured to alternately form regions in the circumferential direction of the cleaning roller.

  In the present invention, the brush bristle region and the porous region may be arranged so as to form a checkered pattern alternately arranged in a circumferential direction and a rotation axis direction of the cleaning roller. Is possible.

  Even with such a configuration, even when the contact state of the cleaning roller with the surface of the object to be cleaned changes to some extent, uniform scraping by the rubbing of the porous region with respect to the adhering material adhering to the surface of the object to be cleaned. Due to the action and the collecting action by the brush bristle region, the function of removing the deposit is favorably maintained.

  In addition, it is desirable that the brush bristle region and the porous region in the present invention are arranged so as to form a spiral shape along the rotation axis direction of the cleaning roller.

  According to such a configuration, the bristle region and the porous region have a transporting action in the axial direction when the cleaning roller rotates, and the deposits collected on the cleaning roller are transported by the cleaning roller. Is smoothly sent out of the machine.

  Further, in the present invention, it is desirable that the raised brush piece in the region constituting the brush bristle region is arranged such that the downstream side is higher than the upstream side in the rotation direction of the cleaning roller.

  According to such a configuration, since the charging potential of the brush bristle region changes so as to increase from the upstream side to the downstream side in the circumferential direction, a charge opposite to the charging potential of the brush bristle region is obtained. After the attached deposits are collected in the brush bristle region, they are sequentially moved toward the downstream side in the circumferential direction, which is the back side in the traveling direction, and the total collected amount is increased.

  In the present invention, the fiber density of the brushed brush pieces in the region constituting the brush bristle region is preferably arranged so that the downstream side is higher than the upstream side in the rotation direction of the cleaning roller.

  According to such a configuration, the gap between the brushed brush pieces constituting the brush bristle region changes in the circumferential direction, and the fibers from the upstream side in the circumferential direction, which is the traveling direction, toward the downstream side. Since the density is increased, the collected matter collected in the brush bristle region moves sequentially toward the downstream side in the circumferential direction, which is the back side in the traveling direction, and the overall recovery amount is increased. The

  In the present invention, the number of cells of the elastic porous member in the region constituting the porous region is preferably configured so that the downstream side is larger than the upstream side in the rotation direction of the cleaning roller.

  According to such a configuration, the adsorbing property of the deposits by the sponge-like member constituting the porous region changes in the circumferential direction, so that the upstream side in the circumferential direction, which is the traveling direction, is the downstream side. As the number of cells is increased toward the surface, the deposit recovery function by the porous region also functions in the downstream region in the circumferential direction where the recovery of the deposit has progressed. Is increased.

  As described above, in the present invention, the surface of the cleaning roller having a large number of brushed brush pieces provided so as to radiate along the circumferential direction, the brush bristle region including the tip of the brushed brush piece, and the A brush region formed by a porous region made of an elastic porous member adjacent to the circumferential direction of the brush bristle region, and a rubbing action by rubbing of the porous region against the adhered matter adhering to the surface of the object to be cleaned; Since it is constructed so that the removal function of the adhered matter is maintained well by the collecting action by the hair region, the cleaning action of the cleaning roller can be performed with a simple configuration in an image forming apparatus using an electrostatic transfer process. Therefore, the cleaning ability of the cleaning apparatus and the image forming apparatus can be greatly improved at low cost.

1 is a longitudinal cross-sectional explanatory view showing an internal structure of a copying machine using an electrophotographic system as an example of an image forming apparatus to which the present invention is applied. FIG. 2 is an enlarged cross-sectional explanatory view showing a configuration of a cleaning roller according to an embodiment of the present invention used in the copying machine shown in FIG. 1. It is a cross-sectional explanatory drawing which represented typically the cleaning effect | action of the deposit | attachment by the cleaning roller concerning one Embodiment of this invention shown in FIG. FIG. 3 is an external perspective explanatory view schematically showing the middle of the manufacturing process of the cleaning roller according to the embodiment of the present invention shown in FIG. 2. FIG. 3 illustrates a structural example of a charging roller as a member to be cleaned used in the copying machine illustrated in FIG. 1, and (a), (b), and (c) are cross-sections illustrating different structural examples. It is surface explanatory drawing. FIG. 4 is an enlarged view of a configuration of a cleaning roller according to another embodiment of the present invention, in which (a) is an external perspective view, and (b) is a plan view. The structure of the cleaning roller concerning other embodiment of this invention is expanded and represented, Comprising: (a) And (b) is a cross-sectional explanatory drawing of the position which differs in an axial direction. It is an external appearance perspective explanatory drawing which expanded and represented the structure of the cleaning roller concerning further another embodiment of this invention. It is a cross-sectional explanatory drawing which expanded and represented the structure of the cleaning roller concerning further another embodiment of this invention. It is a cross-sectional explanatory drawing which expanded and represented the structure of the cleaning roller concerning further another embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, what attached | subjected the same code | symbol in each drawing has the same structure or effect | action, The duplication description about these is abbreviate | omitted suitably.

First, a schematic configuration of the copying machine shown in FIG. 1 will be described as an example of an image forming apparatus to which the present invention is applied. The copying machine 1 shown in the figure is a contact charging system that uses a drum-type electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) 101 as a rotatable image carrier for forming an electrostatic latent image. It is a transfer type electrophotographic image forming apparatus. The paper discharge method indicates a type of internal paper discharge that is generally used in recent years, but is not limited to this in the present invention. Further, the reader unit R is not described in detail because it has little relation to the present invention, and the printer unit Pr is described in detail.

  The photosensitive drum 101 is rotatably supported around a drum axis, and is configured to be rotationally driven at a predetermined speed in a counterclockwise direction indicated by an arrow 102 by a driving mechanism (not shown). . The surface of the rotationally driven photosensitive drum 101 is uniformly charged to a predetermined polarity and potential by a charging unit. As the charging member of the charging means in this embodiment, a contact charging device (roller charging device) using a charging roller 103 is employed. The charging roller 103 is formed of a conductive elastic roller member having a roller shaft body (conductive support body, cored bar), and both end portions of the roller shaft body are rotatably supported via bearing members. Yes. Then, in a state where the central axis of the roller shaft body is arranged so as to be substantially parallel to the drum axis of the photosensitive drum 101, the roller shaft body is brought into contact with the photosensitive drum 101 with a predetermined pressing force. It is configured to rotate following the rotation.

  The charging roller 103 at this time constitutes a member to be cleaned in the present invention, and the charging roller 103 as the member to be cleaned is provided with a rotating brush-like cleaning roller 104 as a cleaning member. . Then, due to the rubbing action caused by the rotation of the cleaning roller (brush roller) 104, the adhering matter adhering to the outer peripheral surface of the charging roller (object to be cleaned) 103 is collected so as to be scraped off. It is possible to prevent the local part or the entire surface from being contaminated with deposits. The description regarding the configuration of the cleaning roller 104 will be described in detail later.

  The roller shaft body of the charging roller 103 is charged with a predetermined DC voltage (DC charging method) or a voltage (AC + DC charging method) in which a predetermined AC voltage is superimposed on a predetermined DC voltage from the charging bias application power source S1. Applied as a bias, the surface of the rotating photosensitive drum 101 is uniformly contact-charged to a predetermined polarity and potential by the charging bias. In this embodiment, the surface of the photosensitive drum 101 is charged to a negative predetermined potential. Then, when the image exposure unit 105 performs image exposure on the charged surface of the photosensitive drum 101, the exposure bright portion on the surface of the photosensitive drum 101 is attenuated to form an image exposure pattern on the surface of the photosensitive drum 101. A corresponding electrostatic latent image is formed. The image exposure unit 105 may be an analog exposure device that performs image projection exposure of a document image, or may be a digital exposure device such as a laser scanner or an LED array. In this example, a laser scanner that performs laser scanning exposure L with a wavelength λ = 780 nm is used as the image exposure means 105.

  The electrostatic latent image formed on the surface of the photosensitive drum 101 as described above is developed as a toner image by the developing unit. In the present embodiment, the developing unit uses a one-component magnetic negative polarity toner as a developer. The used jumping reversal developing device 106 is used. The developing device 106 includes a developing sleeve 107 that is rotationally driven, and a hopper portion 108 for supplying a developer to the developing sleeve 107. The developing device 106 has a length of 0.3 mm between the developing sleeve 107 and the photosensitive drum 101. It is arranged so as to keep a certain interval. A voltage obtained by superimposing a predetermined AC component and DC component is applied to the developing sleeve 107 from the developing bias applying power supply unit S2, whereby the electrostatic latent image on the surface of the photosensitive drum is developed by the developing device. This point will be described in detail later, including toner.

  The toner image formed on the surface of the photosensitive drum 101 reaches the transfer portion T which is a contact nip portion between the photosensitive drum 101 and the transfer roller 109 by the rotation of the photosensitive drum 101 and is fed to the transfer portion T. The recording material P is transferred. The transfer roller 109 is composed of a conductive elastic roller having a roller shaft body (conductive support, cored bar), and both end portions of the roller shaft body are rotatably supported via bearing members. Are arranged substantially in parallel with the drum axis of the photosensitive drum 101 and arranged in contact with the photosensitive drum 101 with a predetermined pressing force. In this embodiment, the transfer roller 109 is configured to rotate following the rotation of the photosensitive drum 101.

  The recording material P fed from the paper feed mechanism unit 110 at a predetermined control timing is synchronized with the image formation on the photosensitive drum 101 by the registration roller 111 and is introduced into the transfer unit T at an appropriate timing. The drum 101 and the transfer roller 109 are nipped and conveyed. While the recording material P passes through the transfer portion T, a DC voltage having a predetermined potential having a polarity opposite to the charging polarity of the toner is applied to the transfer roller 109 from the transfer portion T. In the present embodiment, a positive polarity DC voltage having a predetermined potential is applied. As a result, a positive charge is applied to the back side of the recording material P (the side opposite to the photosensitive drum facing surface side) in the transfer portion T, and the toner image on the photosensitive drum surface is electrostatically applied to the surface of the recording material P. Sequentially transferred.

  The recording material P that has received the transfer of the toner image is separated from the surface of the photosensitive drum 101 as it exits the transfer portion T and is introduced into the fixing device 112. The fixing device 112 in the present embodiment is a heat fixing device having a pressure-contact rotating roller pair of a heat roller 114 and a pressure roller 113, and the recording material P introduced into the fixing device 112 is a pressure-contact nip between the roller pairs 113 and 114. Enters the fixing portion N, which is a portion, and is nipped and conveyed. As a result, the unfixed toner image on the recording material P is fixed as a fixed image on the surface of the recording material by heat and pressure, and then the recording material is discharged outside the apparatus main body as an image formed product.

  On the other hand, the surface of the photosensitive drum 101 from which the recording material has been separated is cleaned by removing residuals such as transfer residual toner and paper dust by the cleaning device 115 and repeatedly used for image formation. As the cleaning device 115 in this embodiment, a blade cleaning device using a casting type cleaning blade 116 as a cleaning member is employed. The casting type refers to a cleaning blade type in which a rubber material or the like is poured into a mold. The cleaning blade 116 rubs the surface of the photosensitive drum 101 to scrape residues from the photosensitive drum surface 101, and the scraped residues are accommodated in the collected toner accommodating portion 117.

  Next, the configuration of a cleaning roller (brush roller) 104 as a cleaning member using the charging roller 103 as a member to be cleaned will be described. That is, as described above, the charging roller 103 as the object to be cleaned is provided with a rotating brush-like cleaning roller 104 as a cleaning member. The cleaning roller 104 is as shown in FIG. Each of both end portions in the axial direction of the rotating shaft 104a arranged so as to extend in the direction of the image forming width (vertical direction in FIG. 2) is rotatably supported via a bearing member (not shown). ing. Then, in a state where the central axis of the rotating shaft 104a is arranged so as to be substantially parallel to the axis of the charging roller 103 that is the object to be cleaned, the outer peripheral portion of the cleaning roller 104 is charged with the charging roller (to be cleaned). Body) 103 so as to be in contact with the outer peripheral surface of the body.

  As the rotating shaft 104a of the cleaning roller (brush roller) 104 described above, for example, a metal core made of a metal cylinder or the inside is hollowed out in the same manner as the shaft (described later) of the charging roller (object to be cleaned) 103. However, the present invention is not particularly limited to this. And the resin fiber which comprises many brushed brush pieces 104b is planted by the outer peripheral side of the rotating shaft 104a so that it may extend radially. The numerous brushed brush pieces 104b are arranged by planting resin fibers over a substantially half circumference in the circumferential direction, and are arranged on the outer circumferential surface of a substantially half circumference of the cleaning roller 104 on which the brushed brush pieces 104b are arranged. A bristle region is formed. In FIG. 2 and FIGS. 3, 7, 9, and 10 described later, the solid line representing the tip portion of the brushed brush piece 104b connected in an arc shape is the maximum of each brushed brush piece 104b. This corresponds to an imaginary line representing the average value of the outer diameter.

  Further, on the outer peripheral surface of the cleaning roller (brush roller) 104, as described above, the remaining substantially half-circular portion adjacent to the brush bristle region in which the raised brush pieces 104b are arranged in the circumferential direction is elastic porous. A porous region formed by exposing the outer peripheral surface of the material member (sponge member) 104c to the outside is disposed. The elastic porous member 104c forming the porous region is formed so as to cover the rotary shaft 104a from the outer peripheral side, and is manufactured by foam molding integrally with the rotary shaft 104a and the brushed brush piece 104b. The And the front-end | tip part (radially outer end part) of the raised brush piece 104b arrange | positioned at the bristle area | region which comprises the outer peripheral surface of the cleaning roller 104, and the elastic porous member ( The outer surface of the sponge member 104c rotates while rubbing against the outer surface of the charging roller 103 that is the object to be cleaned, so that the adhering material adhering to the outer surface of the charging roller 103 is removed. It is made the composition which becomes.

  As described above, the outer peripheral surface of the cleaning roller (brush roller) 104 is adjacent to the brush bristle region formed by exposing the tip of the brushed brush piece 104b to the outside, and the brush bristle region in the circumferential direction. And a porous region formed by exposing an elastic porous member (sponge member) 104c to the outside, and a resin fiber constituting a raised brush piece 104b in the brush bristle region of the porous region For example, a generally known fiber alone or a dispersion of a conductive material can be used. Examples of the fiber material at that time include polyamide (nylon), acrylic, polyester, rayon, and vinylon, and examples of the conductive material include metals such as aluminum, iron, copper, and nickel, and zinc oxide and tin oxide. Examples thereof include conductive oxides such as titanium oxide, and carbon fine particles such as carbon black, graphite, and carbon nanotubes. However, nylon-based polyamides (nylon 6) are not easily affected by various temperature and humidity environments. And carbon black dispersed therein are preferred. In addition, as a characteristic of the resin fiber, it is only necessary to basically recover what has been cleaned with a sponge, so there is no particular attention to thickness or Young's modulus.

The electrical resistance of the resin fibers forming the nap-shaped brush piece 104b is preferably from 10 ⁹ Ω~10 ¹⁵ Ω, electrically can no longer adsorb smaller than a deposit 10 ⁹ Omega, also ^{10 15} Omega If it is larger, the fibers are triboelectrically charged and adsorbed to each other, which tends to be an adverse effect on the recovery capability. In this case, the electrical resistance is measured, for example, by replacing the photosensitive drum 101 with an aluminum drum and, for example, 100 V between the aluminum drum and the rotating shaft (core metal) 104 a of the cleaning roller (brush roller) 104. And the resistance value of the brushed brush piece 104b itself of the cleaning roller 104 is obtained by measuring the current value flowing at that time.

In addition, the flocking density of the resin fibers of the above-described brushed brush piece 104b is not particularly limited, but is set according to the thickness, and is preferably, for example, 50 to 1000 / mm ^2. More preferably, it is 75 to 800 pieces / mm ² .

  Further, the resin fibers forming the above-described brushed brush pieces 104b have different fiber densities and materials in the circumferential direction that is the traveling direction. That is, in the present embodiment, the flocking density that determines the fiber density is configured to increase continuously or stepwise toward the downstream side in the circumferential direction, and a cleaning roller (brush roller). It arrange | positions so that a downstream may become higher than the rotation direction 104 upstream. When the density of the brushed brush piece 104b is changed in this way, the deposit (removed material) collected on the brushed brush piece 104b is on the far side in the traveling direction as the cleaning roller 104 rotates. It moves toward the downstream side in the circumferential direction, and the total amount of deposits collected increases.

  Also, the resin fiber material forming the brushed brush piece 104b is set so that the electrical resistance of the resin fiber increases continuously or stepwise along the circumferential direction, which is the traveling direction. The cleaning roller (brush roller) 104 is arranged so that the downstream side is higher than the upstream side in the rotation direction. In this way, the brushed brush piece 104b is easily charged, and the attached matter (removed matter) is moved, so that the attached matter does not stay on the downstream side in the traveling direction, and the entire attached matter recovery amount is reduced. Increase.

  Next, the elastic porous member (sponge member) 104c constituting the porous region will be described. Examples of the elastic porous member 104c include polyester resins, acrylic resins, melamine resins, epoxy resins, urethane resins, polyurethane resins, silicone resins, urea resins, polyamide resins, and other synthetic resins, ethylene-propylene rubber, epichlorohydrin rubber, silicon, and the like. Synthetic rubber such as rubber and fluororubber, or the above-mentioned synthetic resin and synthetic rubber foam are used. In particular, a polyurethane resin foam can be employed relatively easily.

  The elastic porous member (sponge member) 104c has a conductive filler such as carbon black, zinc oxide, tin oxide, tin oxide-coated barium sulfate and / or a quaternary ammonium salt for imparting conductivity. 1 type or 2 types or more of ionic compounds of the above, and further, if necessary, one type of inorganic fillers such as talc, alumina, silica, etc., or organic fillers such as fine powder of fluororesin or silicon rubber, or Two or more are mixed. In addition, as a paint used for forming the coating film of the elastic porous member 104c, a synthetic resin such as a polyester resin, an acrylic resin, a melamine resin, an epoxy resin, a urethane resin, a silicon resin, a urea resin, or a polyamide resin is used. Furthermore, in order to impart conductivity to the coating film, a conductive filler such as carbon black, zinc oxide, tin oxide, tin oxide-coated barium sulfate and / or ionic conductivity is provided in the same manner as the elastic layer. One type or two or more types of ionic compounds such as ammonium salts are mixed. Furthermore, one or more of inorganic fillers such as talc, alumina and silica, and organic fillers such as fine particles of fluororesin and silicon resin are mixed as necessary, and surfactants, charge control agents, foaming aids are mixed. Agents, foam stabilizers, catalysts, etc. are also added as necessary.

  Further, the elastic porous member (sponge member) 104c has a cell number of preferably 40 to 80/25 mm, and more preferably 45 to 75/25 mm. That is, by setting the number of cells as described above, it becomes easy to take in deposits such as toner and external additives in the cells, and the collected deposits such as external additives are charged in the charging roll 103 and the photoreceptor. This is because the transfer to the drum 101 is facilitated. When the number of cells is more than 80/25 mm, the cell diameter is small, so that the ability to take in the external additive is lowered. Conversely, when the number of cells is less than 40/25 mm, the cell This is because the diameter becomes too large and it is difficult to harden the taken-in external additive to an appropriate size for transferring it to the charging roll 103.

  Here, the number of cells of the elastic porous member (sponge member) 104c described above is set so that the number of holes increases with respect to the traveling direction in the circumferential direction (clockwise direction) as shown in FIG. It is preferable that the cleaning roller (brush roller) 104 is configured so that the downstream side is larger than the upstream side in the rotation direction in order to reduce the stay of deposits (removed materials). With such a configuration, the adsorbing property of the deposit by the elastic porous member 104c constituting the porous region is increased from the upstream side in the circumferential direction, which is the traveling direction, to the downstream side. Even in the region on the downstream side in the circumferential direction where the recovery of the kimono has progressed, the deposit recovery function by the porous region functions, and the total recovery amount is increased.

  Further, in the present embodiment, the outer diameter of the brush bristle region determined by the length A of the resin fiber forming the brushed brush piece 104b is determined by the thickness B of the elastic porous member (sponge member) 104c. Is set to be smaller than the outer diameter of the porous region (A <B). More specifically, the diameter of the cleaning roller (brush roller) 104 is set to φ7 mm to φ14 mm, more preferably φ8 mm to φ13 mm, and the thickness of the elastic porous member (sponge member) 104 c is from 1 mm. It is preferably set to 4 mm. This is because if the cleaning roller 104 has a diameter of 14 mm or more, the cleaning roller 104 becomes too large and basically needs to be driven. If the cleaning roller 104 has a diameter of less than 7 mm, the cleaning area is too narrow. This is because the cleaning property is deteriorated.

  The hardness of the elastic porous member (sponge member) 104c at this time is not particularly limited, but the Asuka C hardness is preferably 0.5 to 50 °, more preferably 0.5 to 40 °, More preferably, it is 0.5-30 degrees. This is because when the Asuka C hardness is 0.5 to 50 °, the occurrence of toner filming can be sufficiently suppressed and the cleaning property is excellent.

  Further, the rotation of the cleaning roller (brush roller) 104 represented by the arrow C in FIG. 3 is set to follow rotation with respect to the driving rotation of the charging roller 103 represented by the arrow D in FIG. If it is not set to follow rotation, it is necessary to use a drive configuration, so that it is difficult to design at a low cost and technical restrictions are increased. Regarding the rotational peripheral speed difference of the cleaning roller 104 with respect to the charging roller 103, the peripheral speed ratio is 40 by adjusting the material of the brushed brush piece 104 b of the cleaning roller 104 and the material of the charging roller (object to be cleaned) 103. It is set to be -95%. If the peripheral speed ratio is less than 40% and slow, the peripheral speed becomes too high and the cleaning roller 104 is rubbed against the charging roller 103, making it difficult to remove the deposit, and the peripheral speed ratio is greater than 95%. This is because both of them rotate at substantially the same speed and the cleaning action of the charging roller 103 is hindered.

  The definition of the peripheral speed ratio in this case is 100% peripheral speed when the surface speed of the rotating shaft (core metal) 104a of the cleaning roller (brush roller) 104 is the same as the speed of the charging roller 103. If the speed of the surface of the rotating shaft 104a of the cleaning roller 104 is half the speed, the peripheral speed ratio is 50%.

  Further, in the present embodiment, the adhesive 104d is applied to the surface of the rotating shaft (core metal) 104a, and the base ends of the above-described many brushed brush pieces 104b are electrostatically applied to the adhesive 104d. The elastic porous member (sponge member) 104c is fixed to the rotating shaft (core metal) 104a by adhesion by the adhesive 104d.

  As the adhesive 104d at this time, for example, an adhesive mainly composed of acrylic resin, polyvinyl acetate, polyurethane, synthetic rubber, natural rubber, or the like is used. A water-based adhesive mainly composed of these resins is preferable because an elastic porous material is used as the base material because the base material is less likely to swell, and an acrylic resin is particularly preferable. Acrylic resins are classified into non-reactive polyacrylic acid esters (non-crosslinked), reactive polyacrylic acid esters (mainly using methylol melamine as a crosslinking agent) and self-crosslinking polyacrylic acid esters. The cross-linking type is often used because it is excellent in water resistance, alkali resistance, solvent resistance and the like. In the case of a reactive acrylic resin, a functional group in which at least one of a carboxyl group, an amide group, an amino group, an epoxy group, and a hydroxyl group is introduced as a functional group may be used. These may be used alone or in combination of two or more. This method is easier to manufacture and is preferred for the present invention.

  Here, although it is the length of the resin fiber which comprises the above-mentioned raising brush piece 104b, it is preferable to judge by the final outer diameter of the cleaning roller (brush roller) 104. That is, as described above, in the present embodiment, the outer diameter of the brush bristle region constituted by the raised brush pieces 104b is the same as the outer diameter of the porous region constituted by the elastic porous member (sponge member) 104c. Or it is set so that it may become smaller than an outer diameter, However, The range whose both outer diameters are 0.1-2.0 mm is preferable. If the outer diameter of the brushed brush piece 104b is large, streak-like image defects are likely to occur. On the other hand, if the difference is larger than 2.0 mm, the step difference between the two becomes large and the charging roller 103 may be damaged by the edge of the elastic porous member 104c. Therefore, by restricting the position of the bearing member that supports both end portions of the rotating shaft 104a of the cleaning roller 104 in the axial direction, the distance between the shafts of the cleaning roller 104 and the charging roller 103 is kept constant, and the brushed brush The tip of the piece 104 b may be separated from the charging roller 103, and at least the elastic porous member (sponge member) 104 c may be rubbed against the surface of the charging roller 103.

  According to the cleaning roller (brush roller) 104 having such a configuration, for example, as shown in FIG. Then, first, the adhering material E is rubbed by the rubbing action when the outer peripheral surface of the elastic porous member (sponge member) 104c forming the porous region comes into contact with the outer peripheral surface of the charging roller (object to be cleaned) 103. Taken. Then, the scraped deposit E is in a floating state as indicated by an arrow F in FIG. 3, and a brushed brush piece 104b constituting a brush bristle region disposed downstream of the porous region. The deposit E is collected inside Long-term cleaning ability is maintained by repeating the process.

  As described above, according to the present embodiment, when the cleaning roller (brush roller) 104 rotates, the porous region and the brush bristle region alternately come to the outer peripheral surface of the charging roller 103 as the object to be cleaned. Therefore, even if the contact state of the cleaning roller 104 with the outer peripheral surface of the charging roller (object to be cleaned) 103 changes to some extent, the porous region is rubbed against the deposit E attached to the outer peripheral surface of the charging roller 103. The removal function of the deposit E is well maintained by the uniform deposit scraping action and the deposit recovery action by the brush bristle region.

  Here, the configuration of the charging roller 103 used in this embodiment will be described. That is, as shown in FIG. 5A, a foamed layer 103b made of a conductive elastic material has an appropriate thickness on the outer periphery of the core metal 103a disposed at the rotation center of the charging roller 103. In addition, a conductive layer 103c made of a soluble fluororesin imparted with conductivity by blending a conductive agent is formed on the outer periphery of the foamed layer 103b. Note that the foam layer 103b of the charging roller 103 in the present invention is preferably a material whose outer peripheral speed is accelerated by elasticity in hardness, such as a foamed conductive rubber. The foamed conductive rubber is not particularly limited, but may be ethylene propylene rubber blended with a conductive material, a copolymer rubber foam of epichlorohydrin and ethylene oxide, or a copolymer rubber of epichlorohydrin and ethylene oxide. A foam made of a material containing a conductive agent can be suitably used.

  In addition, as the conductive material to be blended in the rubber composition described above, conductive powder such as carbon black, graphite, metal, various conductive metal oxides (tin oxide, titanium oxide, etc.), carbon fiber, metal oxide Various conductive resin fibers such as short fibers can be used. The compounding amount at that time can be 2 to 70 parts by weight, particularly 3 to 30 parts by weight with respect to 100 parts by weight of the total rubber component, and is adjusted so as to have a predetermined resistance. In addition, formation of a base layer can be performed by a well-known vulcanization molding method, The thickness is suitably set according to the use etc. of a roll, However It is normally set to 1-5 mm.

Further, as the soluble fluororesin constituting the conductive film layer 103c described above, an amorphous fluororesin soluble in a solvent is used. Specifically, a fluorinated alkyl vinyl ether component is added to a tetrafluoroethylene component. A copolymer into which can be introduced can be used. In addition, as a conductive agent to be blended to impart conductivity to these soluble fluororesins, various commonly used conductive materials such as conductive titanium oxide, carbon, conductive tin oxide, etc. can be used. The blending amount is not particularly limited, but can be about 30 to 300 parts by weight with respect to 100 parts by weight of the fluororesin, whereby an appropriate electrical resistance value as a conductive layer of the conductive roll. Which can be 10 ⁷ to 10 ⁸ Ω.

  The conductive film layer 103c is obtained by adding the conductive material to the soluble fluororesin prepared in the form of a paint dissolved in a solvent, and coating the foamed layer on the foamed layer by a normal coating method such as dipping, brushing or spraying. Then, it can be formed easily by performing forced drying such as natural drying, evacuation or heat treatment. Further, when the conductive layer 103c is formed on the foam layer, in order to adjust the electric resistance value of the conductive roll, as shown in FIG. 5B, the gap between the foam layer 103b and the conductive layer 103c is used. An undercoat layer 103d can also be formed. In this case, the undercoat layer 103d is not particularly limited, but a polyester urethane such as 1,4 butanediol, urethane obtained by chain-extending a diol of ethylene glycol and an ester of adipic acid with MDI (methylenediphenyl isocyanate). Various carbon blacks, conductive titanium oxide, conductive tin dispersed, etc. are preferably used. In addition, N-methoxymethylated copolymer nylon (trade name, resin) conventionally used as a conductive film layer is preferably used as the undercoat layer 103d by adding a conductive agent to the conductive layer. it can.

  Further, the hardness of the charging roller 103 may be general. Its hardness (JIS ASKER C constant load measuring device) is preferably 55 to 40 °. When the angle is larger than 55 °, the charging ability tends to be reduced, and when the angle is smaller than 40 °, dirt unevenness on the brush tends to be easily generated.

  As shown in FIG. 5C, as the charging roller 103, a conductive elastic body layer 103e is formed on the outer periphery of the core metal 103a, and a softener transition preventing layer 103f is formed on the outer periphery thereof. A configuration in which a resistance adjustment layer (or dielectric layer) 103g and a protective layer 103h are formed may be employed.

  Further, a general description of toner that is one of the deposits that adhere to the outer peripheral surface of the charging roller 103 will be given. First, as a method for developing the electrostatic latent image formed on the photosensitive drum 101, a method of developing in a non-contact state with respect to the photosensitive drum 101 (one-component non-contact development), a development in a state of contact with the photosensitive drum 101. There is a method (one-component contact development). Further, there is a method (two-component contact development) in which toner particles mixed with a magnetic carrier are used as a developer, and the developer is conveyed by magnetic force and developed in contact with a photosensitive drum. Further, there is a method of developing the two-component developer in a non-contact state with respect to the photosensitive drum 101 (two-component non-contact development method). Either can be used suitably.

  In this embodiment, the toner used for developing the electrostatic latent image includes a color component agent, a binder resin, an aliphatic hydrocarbon-aromatic hydrocarbon copolymer petroleum resin having 9 or more carbon atoms, a wax, A material having a particle diameter of 7 μm formed of a magnetic agent or the like is used. Conventionally known resins can be used as the binder resin. For example, a polyester resin, a styrene resin, a styrene- (meth) acrylic resin, a styrene-butadiene resin, an epoxy resin, a polyurethane resin, and the like can be given. Such a polyester resin is synthesized from a polyol component and a polycarboxylic acid component by polycondensation. Examples of the polyol component used include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3 butanediol, diethylene glycol, triethylene glycol, and 1,5-butanediol. Further, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol, hydrogenated bisphenol A, bisphenol-A ethylene oxide adduct, bisphenol-A propylene oxide adduct, and the like can be given. Examples of the polycarboxylic acid component include maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, dodecenyl succinic acid, trimellitic acid, pyromellitic acid, and cyclohexanetricarboxylic acid. 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropanetetramethylenecarboxylic acid and their anhydrides Things.

  Further, the aliphatic hydrocarbon-aromatic hydrocarbon copolymer petroleum resin having 9 or more carbon atoms contained in the toner acts as a wax dispersion aid. For this reason, the dispersion of wax in the resin, the low-temperature fixability is maintained, the anti-offset property, the pulverization property, the image density decrease due to the charging deterioration due to the filming of the wax on the developing carrier, the filming on the image carrier The occurrence of image defects on the subject is remarkably improved. The same effect can be obtained when added to a magnetic developer. This aromatic hydrocarbon copolymerized petroleum resin is synthesized from diolefins and monoolefins contained in cracked oil fractions by-produced from ethylene plants that produce ethylene, propylene, etc. by steam cracking of petroleum. is there. A copolymer obtained by copolymerizing an aliphatic hydrocarbon monomer and an aromatic hydrocarbon monomer as described below is desirable. The aliphatic hydrocarbon monomer is at least one selected from isoprene, piperylene, 2-methyl-butene-1, and 2-methylbutene-2. The aromatic hydrocarbon monomer is at least one selected from vinyltoluene, α-methylstyrene, indene, and isopropenyltoluene.

  As the aromatic hydrocarbon monomer, it is more preferable to use a pure monomer having a high monomer purity because the coloring of the resin and the odor during heating can be kept low. The purity of the aromatic hydrocarbon monomer is 95% or more, more preferably 98% or more. The aromatic hydrocarbon monomer is a monomer having 9 or more carbon atoms. In the case of a copolymerized petroleum resin obtained from this monomer and an aliphatic hydrocarbon monomer, a binder resin compared to a copolymerized petroleum resin obtained from an aromatic hydrocarbon monomer having less than 9 carbon atoms and an aliphatic hydrocarbon monomer For example, compatibility with a polyester resin becomes higher. Furthermore, in order to satisfy the pulverization property and heat storage property of the toner, it is preferable that the aliphatic hydrocarbon copolymer having 9 or more carbon atoms has a large amount of aromatic hydrocarbon monomer. However, when the amount of the aromatic hydrocarbon monomer is too large, the dispersibility of the release agent is deteriorated. On the other hand, when there are too many aliphatic hydrocarbon monomers, heat preservation property etc. will fall. Therefore, the weight of the aromatic hydrocarbon monomer amount and the aliphatic hydrocarbon monomer amount is 99: 1 to 50:50, more preferably 98: 2 to 60:40, and still more preferably 98: 2 to 90:10. . The amount used is 2 to 50 parts by weight with respect to 100 parts by weight of the toner binder resin. More preferably, it is 3 to 30 parts by weight. When the amount of the petroleum resin is less than 2 parts by weight, there is no effect on the wax dispersion. When the amount exceeds 50 parts by weight, the toner tends to be excessively pulverized, and the particle size of the toner becomes small in the developing machine. Occurs, the image density becomes low, and the developability may be lowered.

  Furthermore, the fluidity of the toner can be improved by attaching fine powder as a surface treatment agent (external additive) to the surface of the toner. This is because hydrophobic silica or the like is used as such a fine powder. When hydrophobic silica is attached to the surface of the toner, not only the fluidity is improved, but also the cleaning property and charging property of the toner can be improved. Moreover, fine powder other than hydrophobic silica can also be used. For example, fine powders of oxides such as titanium oxide, alumina, cerium oxide, fatty acid metal salt, polyvinylidene fluoride, polystyrene, magnesium, zinc, aluminum, cobalt, iron, zirconium, manganese, chromium, cerium, strontium, tin, etc. It can be used. In addition, inorganic oxide fine powders that are complex metal oxides such as calcium titanate, magnesium titanate, strontium titanate, barium titanate, calcium zirconate, barium zirconate, barium stannate, calcium stannate are also available. It is. Examples of the carbonate compound include calcium carbonate, magnesium carbonate, and barium carbonate. Among these, hydrophobic silica is often used for color toners, and strontium titanate is often used for monochrome toners.

  The amount of the surface treatment agent used is usually 0.1 to 20% by mass with respect to 100 parts by mass of the toner. The effect is further increased by using the abrasive particles as a surface treatment agent. However, in this case, the mass should be 1% or less if it is limited to this abrasive. When the content is more than 1%, developability and density decrease are affected. Deposits that adhere to the outer peripheral surface of the charging roller 103 according to the present embodiment are mainly the above-described external additives.

  Here, although a specific example is given and demonstrated, it is natural that this invention is not limited to the following.

[Example 1]
In Example 1, first, regarding the charging roller 103, a foamed layer having a thickness of 3.8 mm was formed on a cored bar having a diameter of 8 mm under a vulcanization condition of 230 ° C. × 3 minutes, and the preparation at that time was as follows.
[Adjustment of foam layer forming material]
Ethylene propylene rubber 100 parts by weight Oil 70 parts by weight Polyethylene glycol 1 part by weight Foaming agent 3 parts by weight

  Next, on the foamed layer, an undercoat layer comprising 200 parts by weight of carbon dispersed in 100 parts by weight of urethane obtained by chain-extending a polyester acid diol of adipic acid and 1,4 butanediol with MDI (methylene diphenyl isocyanate) is 200 μm thick. In addition, 170 parts by weight of conductive tin oxide is dispersed in 100 parts by weight of Belflon manufactured by Nippon Oil & Fats Co., Ltd., which is a paint of Lumiflon from Asahi Glass Co., Ltd. Was dipped into a roll comprising the foam layer and the undercoat layer, and a conductive film layer having a thickness of 10 μm was formed on the roll surface to obtain a charging roll. The hardness of the charging roller at this time was 45 ° with Asker C.

The cleaning roller (brush roller) 104 was prepared as follows.
A stainless steel core material with a diameter of 8 mm and a length of 340 mm was adopted as the rotating shaft (core metal) 104a, and a hot melt adhesive (after drying) was applied to the surface of the rotating shaft (core metal) 104a over a thickness of about 20 μm. . Further, as an elastic porous body in which a hole through which the rotating shaft (core metal) 104a passes is formed in advance, polyurethane is synthesized by using an amine catalyst as a raw material composed of polyester polyol and tolylene diisocyanate, and further, water as a blowing agent and Using a silicone foam stabilizer as a foam stabilizer, a urethane-based foamed resin material 104c ′ was prepared to have a square bar shape as shown in FIG. The obtained urethane-based foamed resin material 104c ′ was cut into a length of 325 mm with a cross-sectional dimension of 20 mm × 20 mm, and a hole was drilled in the cut urethane-based foamed resin material 104c ′ (Asuka C hardness: 1 °, cell Number: 50 pieces / 25 mm, density: 30 kg / m ³ , volume resistivity: 10 ¹² Ω), and a rotating shaft (core metal) 104 a was inserted into the hole and bonded by heating. Thereafter, the outer diameter surface was ground and polished to produce a cleaning roller material (diameter: 14 mm) provided with an elastic porous layer. The material is left about half in the circumferential direction as in the cross section shown in FIG. 3, and the remaining part is peeled off. And the hot-melt-adhesive agent mentioned above is apply | coated to the peeled-off part, and the insulating nylon 66 fiber (length; 1.) is used for the voltage of 60 kV using an electrostatic flocking device (made by Toyo Denso Co., Ltd.). 5 mm, thickness: 3 denier) is implanted (plant density: 100 / mm ² ), dried in a hot-air circulating drying furnace adjusted to a temperature of 80 ° C. for 30 minutes to fix the fibers, and as described above A cleaning roller 104 was manufactured.

  The charging roller 103 and the cleaning roller (brush roller) 104 are put in a copying machine iR3045 (manufactured by Canon Inc.) whose main body is modified as shown in FIG. 1, and the charging roller 103 is rotated at a rotational speed of 230 mm / s. At the same time, the rotational speed was set to 230 mm / s, and the peripheral speed ratio of the cleaning roller 104 was set to 90%. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (300K sheets), and the charging roller 103 is stained (50K, (100K, 150K, 200K, 250K, 300K sheets) As a result of confirmation, Example 1 was very good and had no problem on the image. Further, the level of contamination during durability was at a level that does not cause any problem, and so-called streak-like contamination did not occur. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 2]
In the second embodiment, the brush bristle region and the porous region in the cleaning roller (brush roller) 104 described above are arranged so as to form a spiral shape along the axial direction of the rotation shaft 104a. Regarding the preparation of the cleaning roller 104, an elastic porous member 104c formed by applying hot melt to the rotating shaft (core metal) 104a in the same manner as in Example 1 so as to form a band plate shape having a width of 50 mm and a thickness of 3 mm is shown in FIG. As shown in FIG. 6, it was spirally wound so that the twist angle θ was 45 °. In addition, electrostatic flocking similar to that in Example 1 was performed in the gap portion of the elastic porous member 104c, and a cleaning roller as shown in FIG. 6 was created. The cleaning roller 104c according to the second embodiment has a cross-sectional shape as shown in FIG.

  As in the first embodiment, this cleaning roller is put into a copying machine iR3045 (manufactured by Canon Inc.) whose main body is modified as shown in FIG. 1, the rotational speed of the photosensitive drum 101 is set to 230 mm / s, and the charging roller 103 is simultaneously used. The rotational speed was 230 mm / s, and the peripheral speed ratio of the cleaning roller 104 was 90%. Under normal conditions (20 ° C / 50%), an image with a toner applied amount of 0.025 g / A4 size was intermittently subjected to a sheet passing image test (300K sheets), and the charging roller was stained (50K, 100K). 150K, 200K, 250K, 300K sheets). It was very good and no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 3]
In Example 3, as shown in FIG. 7B, only a part of the elastic porous member (sponge member) 104c in Example 1 described above is left (5% in this example), and the other parts. A brush similar to Example 1 was prepared except that electrostatic flocking was performed. In the same manner as in the first embodiment, the charging roller and the brush are put into a copying machine iR3045 (manufactured by Canon Inc.) whose main body is modified as shown in FIG. 1, the rotational speed of the photosensitive drum 101 is set to 230 mm / s, and the charging roller 103 At the same time, the rotational speed was set to 230 mm / s, and the peripheral speed ratio of the cleaning roller 104 was set to 90%. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (300K sheets), and the charging roller 103 is stained (50K, 100K, 150K, 200K, 250K, 300K sheets). It was very good and no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 4]
Further, in the third embodiment, the bristle region and the porous region are arranged in a checkered pattern alternately arranged in the circumferential direction and the rotation axis direction of the cleaning roller 104. A part of the elastic porous member (sponge member) 104c is left as a checkered element piece portion of 6 mm (circumferential direction) × 20 mm (rotational axis direction) as shown in FIG. Electric hair transplantation is performed, and the rest is the same as in Example 1. In the same manner as in Example 1, the charging roller 103 and the cleaning roller 104 are put in a copying machine iR3045 (manufactured by Canon Inc.) whose main body is modified as shown in FIG. 1, and the rotational speed of the photosensitive drum 101 is set to 230 mm / s. At the same time, the charging roller 103 was rotated at 230 mm / s. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (300K sheets), and the charging roller 103 is stained (50K, (100K, 150K, 200K, 250K, 300K sheets). As a result, it was confirmed that the image was very good and there was no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 5]
In the fifth embodiment, as described above, the brushed brush pieces 104b constituting the bristle region have different fiber densities in the circumferential direction as shown in FIG. In this arrangement, by changing the bias at the time of flocking, the flocking density is changed in approximately three steps (see symbols G, H, and I) in the circumferential direction as surrounded by a broken line (50 Book / mm ² , 75 pieces / mm ² , 100 pieces / mm ² ). In the same manner as in Example 1, the charging roller 103 and the cleaning roller 104 are put into a copying machine iR3045 (manufactured by Canon Inc.) whose main body is modified as shown in FIG. 1, and the rotational speed of the photosensitive drum 101 is set to 230 mm / s. The rotation speed of the charging roller 103 was also set to 230 mm / s. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (500K sheets), and the charging roller 103 is stained (50K, (100K, 150K, 200K, 250K, 300K, 400K, 500K sheets). As a result, it was found that the image was very good and there was no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 6]
Further, in the sixth embodiment, the brushed brush piece 104b constituting the brush bristle region has a different electric resistance in the circumferential direction as shown in FIG. Arranged, and the resistance of the flocked fiber is changed in approximately three steps (see J, K, L) as surrounded by the broken line in the figure (10 ¹¹ Ω, 10 ¹² Ω, 10 ¹³ Ω) )created. In the same manner as in Example 1, the charging roller 103 and the cleaning roller 104 are put in a copying machine iR3045 (manufactured by Canon Inc.) modified as shown in FIG. 1, and the rotational speed of the photosensitive drum 101 is set to 230 mm / s. At the same time, the charging roller 103 was rotated at 230 mm / s. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (500K sheets), and the charging roller 103 is stained (50K, (100K, 150K, 200K, 250K, 300K, 400K, 500K sheets). As a result, it was found that the image was very good and there was no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Example 7]
The seventh embodiment is different from the first embodiment described above in that the elastic porous member (sponge member) 104c constituting the porous region is different in the circumferential direction as shown in FIG. The number of cells of the elastic porous member (sponge member) 104c is set to approximately three levels (reference numerals M, N, (Refer to P) were prepared (25 pieces / 25 mm, 50 pieces / 25 mm, 75 pieces / 25 mm). In the same manner as in Example 1, the charging roller 103 and the cleaning roller 104 are put in a copying machine iR3045 (manufactured by Canon Inc.) modified as shown in FIG. 1, and the rotational speed of the photosensitive drum 101 is set to 230 mm / s. At the same time, the charging roller 103 has a rotational speed of 230 mm / s, and the circumferential speed ratio of the cleaning roller 104 is 90%. In a normal environment (20 ° C./50%), an image having a toner applied amount of 0.025 g / A4 size is intermittently subjected to a sheet passing image test (500K sheets), and the charging roller 103 is stained (50K, (100K, 150K, 200K, 250K, 300K, 400K, 500K sheets). As a result, it was found that the image was very good and there was no problem on the image. Moreover, it was a level which does not have a problem also about how to stain at the time of durability. Furthermore, no streak-like dirt was generated. In addition, the scattering in the main body was maintained at a level with no problem, and there was no problem on the image.

[Comparative Example 1]
In Comparative Example 1, a cleaning roller was used at the stage where only the elastic porous member (sponge member) 104c in Example 1 described above was used, and the same examination as in Example 1 was performed. As the number of durable sheets progressed, the deposits collected in the sponge scattered around and eventually entered the developing unit located below, and an image defect occurred at 150K.

[Comparative Example 2]
Further, in Comparative Example 2, the same examination as in Example 1 was performed using the cleaning roller at the stage where only the raised brush pieces 104b by electrostatic flocking were used in Example 1 described above. Although there was no scattering, as the number of durable sheets progressed, streak-like dirt was conspicuous, and an image defect finally occurred at 140K.

[Comparative Example 3]
Furthermore, in Comparative Example 3, the same examination as in Example 1 was performed except that the hair length of the resin fiber of the brushed brush piece 104b was 2.5 mm in Example 1 described above. In the cleaning roller 104 according to this example, the outer diameter of the brushed brush piece 104b is larger than the outer diameter of the elastic porous member (sponge member) 104c. This was examined in the same manner as in Example 1. Although it was better than Comparative Example 1, streaks were conspicuous and streaky image defects occurred at 180K.

  As mentioned above, although the embodiment of the invention made by the present inventor has been specifically described, it is needless to say that the present invention is not limited to the above embodiment and can be variously modified without departing from the gist thereof. Yes.

  For example, in the above-described embodiment, the present invention is applied to a copying machine, but the present invention is similarly applied to other image forming apparatuses such as a printer / facsimile and various other apparatuses. Is something that can be done.

  As described above, the cleaning device and the image forming apparatus according to the present invention can be widely applied to a wide variety of image forming apparatuses such as printers and copiers, and other various apparatuses.

101 Photosensitive drum 103 Charging roller (object to be cleaned)
104 Cleaning roller (cleaning member; brush roller)
104a Rotating shaft (core)
104b Brushed brush piece (resin fiber; brush hair region)
104c Elastic porous member (sponge member; porous region)
104d Adhesive 105 Image exposure means 106 Developing device 107 Developing sleeve 108 Hopper portion 109 Transfer roller 110 Paper feeding mechanism portion 111 Registration roller 112 Fixing device 113 Pressure roller 114 Heat roller 115 Cleaning device 116 Cleaning blade 117 Collected toner storage portion R Leader part Pr Printer part E Deposits P Recording material T Transfer part

Claims (8)

In the cleaning apparatus configured to remove the deposits on the surface of the cleaning object by rubbing the surface of the rotating object to be cleaned by the cleaning roller supported by the rotating shaft,
The outer peripheral surface of the cleaning roller is configured to form regions alternately in the circumferential direction of the cleaning roller, and a brush bristle region composed of a brushed brush piece, and an elasticity disposed adjacent to the brush bristle region. A cleaning device comprising a porous region made of a porous member, and at least the porous region rubs against the surface of the object to be cleaned.   The cleaning device according to claim 1, wherein an outer diameter of the brush bristle region of the cleaning roller is smaller than an outer diameter of the porous region.   3. The cleaning device according to claim 1, wherein the brush bristle region and the porous region are formed in a checkered pattern alternately arranged in a circumferential direction and a rotation axis direction of the cleaning roller. .   The cleaning device according to claim 1, wherein the brush bristle region and the porous region are arranged in a spiral shape along a rotation axis direction of the cleaning roller.   The cleaning according to any one of claims 1 to 4, wherein the electric resistance of the brushed brush piece in the region constituting the brush bristle region is higher on the downstream side than on the upstream side in the rotation direction of the cleaning roller. apparatus.   The cleaning according to any one of claims 1 to 4, wherein the fiber density of the brushed brush pieces in the region constituting the brush bristle region is higher on the downstream side than on the upstream side in the rotation direction of the cleaning roller. apparatus.   The cleaning according to any one of claims 1 to 4, wherein the number of cells of the elastic porous member in the region constituting the porous region is larger on the downstream side than on the upstream side in the rotation direction of the cleaning roller. apparatus. An image forming unit that forms a toner image on a recording medium,
An image forming apparatus, wherein the image forming unit includes the cleaning device according to claim 1.

Images