Abstract: A charger includes: a charging brush which is rotatably provided and is brought into contact with an image carrier to charge the surface of the image carrier; a charging roller which is brought into contact with the image carrier at a portion on the downstream side relative to the charging brush in the rotational direction of the image carrier to charge the surface of the image carrier; and a controller which controls voltages applied to the charging brush and charging roller, wherein the controller controls voltages applied to the charging brush and charging roller such that one-fifth of the absolute value of a charging brush current flowing between the image carrier and charging brush is lower than the absolute value of a charging roller current flowing between the image carrier and charging roller.

Abstract: An electrostatic charging apparatus, includes: an endless-shaped electrostatic charging belt having electrical conductivity, the electrostatic charging belt being arranged in a state of having a predetermined contact zone being in contact with a moving to-be-charged body and moving in the same direction as a moving direction of the to-be-charged body; and plural electrode members including at least a first electrode member and a second electrode member, the plural electrode members being provided inside the electrostatic charging belt, and the first and second electrode members being provided on both sides of the contact zone of the electrostatic charging belt in the moving direction thereof so as to press the electrostatic charging belt against the to-be-charged body and forming gaps that permit electric discharge between the to-be-charged body and the electrostatic charging belt, the gaps being adjacent to the respective sides of the contact zone of the electrostatic charging belt.

Abstract: A charging device for electrically charging an image bearing member, includes a contact charging member contactable to the image bearing member to charge the image bearing member, the contact charging member being supplied only with a DC voltage; and a contact member contacted to the charging member, wherein the image bearing member is adapted to carry a toner image of toner which contains an externally added material comprising silica, wherein work functions of the charging member, the contact member and the silica satisfy, (the work function of the contact member)>(the work function of the silica)>(the work function of the charging member).

Abstract: A xerographic marking engine adjusts a charging actuator, such as an AC peak-to-peak voltage or an AC peak-to-peak AC current, based upon toner patch density measurements made using, e.g., a toner patch density sensor. The sensor is used to detect a knee in a toner mass density curve obtained by sweeping an AC peak-to-peak voltage or an AC peak-to-peak current. Once the knee is located, an AC charging actuator peak-to-peak voltage or AC peak-to-peak current is determined that reduces the amount of positive charge that is deposited onto the surface of the photoconductor, thereby extending its life while maintaining acceptable print quality. The described approach may improve photoconductor life without significantly increasing production costs or complexity.

Abstract: Disclosed is a photoconductive member including a self-healing composite coating having a polymer matrix, a photoconductive component, a healing material encapsulated within nano- or microcapsules, and an optional catalyst, that is capable of repairing physical damage to the photoconductive member when the capsule ruptures. Also disclosed is photoconductive member including a substrate, an undercoat layer, a charge generating layer, a charge transport layer, and an optional protective overcoat layer; in which one layer of the photoconductive member further includes a healing material encapsulated within nano- or microcapsules and an optional catalyst, and that is capable or reparing physical damage to the photoconductive member when the capsule ruptures. Also disclosed is an imaging forming apparatus including same.

Abstract: An image forming apparatus includes a rotatable image carrying member, on a surface of which an electrostatic latent image is formed, and a charging roll that is in contact with the image carrying member to charge the surface of the image carrying member to a prescribed potential. The charging roll has, in non-image forming areas in both end parts in an axial direction of the charging roll, large diameter parts having a larger outer diameter than an outer diameter of a center part of the charging roll, and small diameter parts having a smaller outer diameter than the outer diameter of the center part inside the large diameter parts in the axial direction. Differences in outer diameter of the large diameter part and the small diameter part from the outer diameter of the center part each is approximately 0.25% or less of the outer diameter of the center part.

Abstract: A release agent applicator applies release agent to an imaging drum and absorbs release agent metered from the drum to extend the operational life of a image drum maintenance unit. The applicator includes a reservoir for storing release agent, the reservoir having a plurality of perforations for enabling release agent to seep from the reservoir, a containment membrane mounted to the reservoir for wicking release agent from the perforations of the reservoir, and a delivery layer mounted to the containment membrane for delivering release agent from the containment membrane to an imaging drum that is in contact with the delivery layer. The delivery layer is matched to the containment membrane to maintain a saturation rate for the delivery layer in a predetermined range and the delivery layer has an uptake rate for release agent contacting an external boundary of the delivery layer that is greater than a release agent supply rate from the containment membrane to the delivery layer.

Abstract: In an electrophotographic photosensitive member having a support, a conductive layer formed on the support, an intermediate layer formed on the conductive layer, and a photosensitive layer formed on the intermediate layer, the conductive layer has been formed by using a conductive layer coating fluid which contains TiO2 particles coated with oxygen deficient SnO2 having an average particle diameter of from 0.20 ?m or more to 0.60 ?m or less, and has a volume resistivity of from more than 8.0×108 ?cm to 1.0×1011 ?cm or less. The electrophotographic photosensitive member can keep charging lines from occurring.

Abstract: A charging unit available in a process unit detachably attached to an image forming apparatus includes a charging member configured to uniformly charge a surface of an image carrying member while contacting the image carrying member, and a charge bias applying unit configured to apply a charge bias superimposing a direct current voltage on an alternating current voltage to the charging member. The alternating current voltage satisfies a relational expression of “Vpp×0.4/t?8.8×103”, “Vpp” representing a peak-to-peak voltage of the alternating current voltage in the charge bias, and “t” representing a time period from a first point of a swing of a wave component starting to swing by a large amount to a same polarity as the direct current voltage of the charge bias to a second point of the swing of the wave component reaching approximately 80% of an amplitude of the wave component.

Abstract: There provides an electrophotographic photoreceptor using a novel amine compound which has an excellent effect of ozone resistance and can be used for providing an electrophotographic photoreceptor having no adverse effect on other characteristics, and an image forming apparatus including the photoreceptor. The aim is attained by an electrophotographic photoreceptor formed by stacking a single layer type photosensitive layer containing a charge generating material and a charge transporting material, or a layered photosensitive layer, in which a charge generation layer containing a charge generating material and a charge transporting layer containing a charge transporting material are stacked in this order, on a conductive substrate made of a conductive material, wherein the single layer type photosensitive layer or the charge transporting layer of the layered photosensitive layer contains a specific amine compound.

Abstract: An image forming device includes a charging roller that charges a body-to-be-charged by press-contacting and is rotated by the rotating body-to-be-charged, a first receiving portion that supports a supporting portion provided at the charging roller, and causes the charging roller to press-contact the body-to-be-charged, a cleaning member that press-contacts a surface of the charging roller and cleans the charging roller, and a second receiving portion that supports a supporting portion provided at the cleaning member, and causes the cleaning member to press-contact the charging roller. At least one of the first and second receiving portions imparts a degree of freedom at a first receiving portion side to the supporting portion of the charging roller in a direction of press-contacting the body-to-be-charged, and imparts a degree of freedom at a second receiving portion side to the supporting portion of the cleaning member in a direction of press-contacting the charging roller.

Abstract: An image forming apparatus has an organic photoconductor having a surface layer containing fluorine-containing resin particles whose number average primary particle size is not less than 0.02 ?m and is less than 0.20 ?m; a charging device to charge by bring an charging member in contact with the organic photoconductor; a latent image forming device to for a latent image on the organic photoconductor; a developing device to visualize the latent image with toner and to form a toner image on the organic photoconductor; and a transferring device to transfer the toner onto a transfer material.

Abstract: To provide a novel triamine compound usable for providing an electrophotographic photoreceptor having excellent in effect of an ozone resistance, and causing no adverse effect in other characteristic aspects, and a method for producing the same, as well as an electrophotographic photoreceptor using the triamine compound, and an image forming apparatus having the same, there is provided the electrophotographic photoreceptor formed by laminating a monolayer type photosensitive layer containing a charge generating material and a charge transporting material, or a laminate type photosensitive layer having a charge generating layer containing the charge generating material and a charge transporting layer containing the charge transporting material laminated in this order, on a conductive supporting member made of a conductive material, the monolayer type photosensitive layer or the charge transporting layer of the laminate type photosensitive layer containing a specific triamine compound.

Abstract: To provide an electrically conductive polymer member, which can be stably used with a reduced variation in electrical resistance even when its use environment is changed or continuous energization is conducted, and furthermore, a transfer roller and an image forming device, which can stably produce good images by using the electrically conductive polymer member. An electrically conductive polymer member is formed from an electrically conductive polymer material prepared by adding a quaternary ammonium salt and a lithium imide to a base polymer. When the amounts of compounding of the quaternary ammonium salt and the lithium imide are assumed to be x parts by weight and y parts by weight, respectively, it is preferable that x and y satisfy the following formula: 0.009?(y/x)?0.019. A transfer roller and an image forming device are provided with their respective electrically conductive polymer members.

Abstract: A charging apparatus which is excellent in charging uniformity and thus allows a to-be-charged body to be charged uniformly and in which the generation of discharge products can be reduced, is provided. In the charging apparatus, ions are generated under the difference in electrical potential between the discharge electrode and the induction electrode produced in the ion generating section. The generated ions are caused to flow toward the counter electrode, whereupon the to-be-charged body arranged between the ion generating section and the counter electrode is charged.

Abstract: An image forming apparatus includes an image bearing member; a plurality of chargers for injection charging of the image bearing member; a latent image forming device, disposed downstream of the plurality of charging members with respect to a moving direction of a peripheral surface of the image bearing member, for forming a latent image on the image bearing member having been charged by the plurality of charging members; a potential detecting device for detecting a surface potential of the image bearing member after passing by the plurality of charging members, wherein the plurality of chargers include a first charger and a second charger disposed at a most downstream position with respect to the moving direction, and wherein the image forming apparatus is operable in a control mode in which a bias voltage applied to the first charger is changed with a bias voltage applied to the second charger unchanged.

Abstract: An electrophotographic photoreceptor comprising laminating a monolayer type photosensitive layer containing a charge generation material and a charge transport material or a laminate type photosensitive layer obtained by laminating a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material in this order, on a conductive support, wherein the charge transport layer of the monolayer type photosensitive layer or laminate type photosensitive layer contains an enamine compound represented by the following formula (1).

Abstract: An image forming apparatus includes: an image carrier that rotates; and a charging member that is provided opposingly to the image carrier, and that charges a surface of the image carrier, wherein a discharge inhibitor that suppresses a discharge in an axial end portion is interposed in a portion where the charging member is opposed to the image carrier.

Abstract: A technology capable of realizing a stable charging performance in an image forming apparatus employing a contact charging system is provided. A charging device is configured to have a charging member to which a prescribed bias voltage is applied and which comes into contact with an image carrying surface of an image carrier to charge the image carrying surface; and a particle supply section configured to supply a charging auxiliary particle made of a conductive particle having a diamond particle contained therein in a portion coming into contact with the image carrying surface in the charging member.

Abstract: An image forming apparatus includes at least a latent image carrier, a latent image forming mechanism, a developing mechanism and a charger. The latent image carrier bears a latent image. The latent image forming mechanism forms the latent image on the latent image carrier. The developing mechanism develops the latent image on the latent image carrier with toner. The charger includes a conductive member supplied with a bias voltage while contacting a surface of the latent image carrier, and charges at least one of the surface of the latent image carrier and a toner adhering to the surface thereof through the conductive member. A tensile strength of the conductive member at break is no less than 10 MPa and no more than 40 MPa, and a contact pressure between the conductive member and the latent image carrier is no less than 4 kN/m2 and no more than 15 kN/m2.

Abstract: A charging device includes a charging member that contacts a member to be charged, charges the member with a predetermined voltage applied to the charging member, and includes a surface layer containing a resin solid and a conductive agent of approximately 10 wt. % or more with respect to the resin solid content.

Abstract: A charging technique in which the generation of ozone is suppressed and charging efficiency can be improved is provided. There are included an elastic body to come in contact with a body to be charged, the elastic body including a portion which comes in contact with the body to be charged and is formed of a material containing a diamond particle, and a voltage application unit to charge the body to be charged by applying a specified bias voltage through the elastic body to the body to be charged.

Abstract: A charging member is disclosed having a support and at least one cover layer provided on the support., The cover layer has an outermost layer of the cover layer placed at the outermost surface of the charging member; the outermost layer contains i) composite particles composed of first metal oxide particles coated with carbon black, ii) second metal oxide particles and iii) a binder.

Abstract: A first bearing member and a second bearing member fit in a first side and a second side of a rotating shaft in the axial direction, respectively. The first bearing member is held by a supporting portion provided in a casing on a side corresponding to an emplacing member of an image carrier drum. The second bearing member is held by fitting in a fit-in portion from inside. A wall surface that regulates a charging roller in a longitudinal direction is formed on the second bearing member to protrude from a wall surface rotatably and pivotally supporting the charging roller.

Abstract: A cleaning device includes a cleaning roller, a supporting portion and a guiding portion. The cleaning roller has a core and a cleaning member provided around the core, the cleaning member contacting and cleaning a charging roller by rotation of the cleaning roller, the charging roller charging an image carrier carrying an image. The supporting portion supports the core rotatably in a state in which the cleaning member is in contact with the charging roller. The guiding portion movably guides the core, which is supported by the supporting portion, in a direction different from a direction of a straight line passing through a rotational center of the charging roller and a rotational center of the cleaning roller.

Abstract: Imaging methods, image engines, and photoconductor charging systems are described. According to one embodiment, an imaging method includes providing a charge device configured to provide an electrical charge to a surface of an imaging member which is usable for imaging, moving a surface of the charge device adjacent to the imaging member and a bias member, during the moving, first charging a discharged portion of the surface of the charge device using the bias member providing a charged portion of the surface of the charge device, during the moving, second charging a portion of the surface of the imaging member using the charged portion of the charge device, the second charging providing the discharged portion of the surface of the charge device, and repeating the first charging and the second charging during the moving.

Abstract: An image forming apparatus includes an image bearing member, and first and second chargers. Each of the chargers includes a magnetic member for generating magnetism, has a holding member for holding magnetic particles by a magnetic force, and charges the image bearing member by bringing the magnetic particles in contact therewith. The magnetic member of each of the chargers has a magnetic pole facing the image bearing member. The second charger is located at the tail end in the image bearing member rotational direction, but before a position at which an image is formed on the image bearing member. In the image bearing member rotation direction, and relative to a position at which the image bearing member comes closest to the holding member, the first charger's magnetic member has a peak magnetic force positioned downstream, and the second charger's magnetic member has a peak magnetic force positioned upstream.

Abstract: The present invention relates to an image forming apparatus including an electrophotographic photosensitive member provided with a substantially cylindrical body having outer circumference on which a photosensitive layer with a latent image forming area is formed, and a contact electrification means positioned substantially parallel to the axial direction of the electrophotographic photosensitive member. A nip width of a contact area between the photosensitive layer and the electrification means is larger at a middle portion than at end portions of the latent image forming area. Preferably, the nip width becomes larger gradually or stepwise as proceeding from the end portions to the middle portion of the latent image forming area.

Abstract: A method of forming a toner image employing a photoreceptor is described. The photoreceptor comprises a photosensitive layer on a cylindrical conductive substrate, Formula (1) and Formula (2) are held, 0<Pmax<2P??Formula (1) 2?(Pmax/D)×100?50??Formula (2) wherein P (?m) is the average of the coating layer thickness in central section in the width direction of the photoreceptor, Pmax (?m) is average of the image forming region, and D (?m) is average of distance between point, at which said maximum value is obtained, and edge of the coating layer.

Abstract: Charging roller has at least a support member and a conductive covering member, the charging roller where a value of tan ? expressed in a ratio of a storage elastic modulus and a loss elastic modulus by dynamic viscoelasticity in a cross sectional direction of the charging roller at 25° C. is 0.2 or more in a range of 1 to 20 kHz and 0.2 or less in a range of 1 to 10 Hz, or a charging roller where the conductive covering member is constructed of two or more layers and a value of tan ? in at least one layer other than a surface layer is 0.2 or more at 10 Hz in a range of 10 to 50° C. and a value of tan ? in a cross sectional direction of the whole charging roller is 0.2 or less at 10 Hz in a range of 10 to 50° C.

Abstract: A charging apparatus having a charging device for contact charging a rotatable member. The charging device rotates upon reception of a drive force from a drive force transmitting device. The axis of rotation of the charging roller and the axis of rotation of the photoreceptor drum intersect each other. It is a characteristic of the invention that a force received by the charging device from the drive force transmitting device and a force generated between charging device and the rotatable member are oriented in the same direction. With this arrangement, the thrust position of the charging device when the charging device is driven is stabilized.

Abstract: An image forming apparatus includes an image bearing member, charging device which is in contact with the image bearing member and charges the image bearing member, development device which forms a toner image on the image bearing member and recovers a residual toner remaining after the transfer from the image bearing member, transfer device which transfers the toner image on the image bearing member onto a transfer material, auxiliary charging device which is positioned at a downstream side of the transfer device and at an upstream side of the charging device in a rotating direction of the image bearing member, which is in contact with the image bearing member and which is given a voltage of a polarity opposite to that of the developing toner, and voltage selecting device which selects the voltage applied to the auxiliary charging device based on the potential of the image bearing member after the transfer.

Abstract: A metal holder has a V-shape in cross-section formed by two arm sections. PET sheets are attached to mutually opposed surfaces of respective arm sections, and part of each PET sheet extends toward the electrically-conductive roller beyond the arm section. Flocked sheets are attached to the surfaces of the respective PET sheets opposite the electrically-conductive roller, and contact the electrically-conductive roller.

Abstract: A charging device charging a photosensitive medium of an image formation apparatus while being in contact with the photosensitive medium, supports both ends of a charging member having a plate-shaped elastic member by a support member, so that the charging member has a semicircular section. A curved surface of the charging member contacts a surface of the photosensitive medium to maintain a predetermined contact nip and a contact linear pressure. The charging device controls a total resistance by adjusting a material, a thickness, a contact area, and a radius of the charging member, and maintains the contact linear pressure and the contact nip from the photosensitive medium. As a result, the charging device can easily adjust an electric resistance, minimizing variations of the contact linear pressure and the contact nip, material and processing expenses can be cut down, and productivity of the charging device is improved.

Abstract: A contact charger for charging a charging target (e.g., a photosensitive member) includes a charging brush to be in contact with the charging target, and auxiliary charging particles to be interposed between the brush and the charging target. The auxiliary charging particle takes an acicular form having an aspect ratio from 2 to 10000, and satisfies a relationship of (L2/T?200) between a length L (?m) of a long axis of the particle and a thickness of T (deniers) of a brush fiber of the brush.

Abstract: In a charging member having a support and one or more cover layer(s), the ten-point average surface roughness of the surface of the charging member, the height of a hill of the surface of the charging member, the area at the part of the hill, and the area of a region surrounded by hills each having the height H (?m) and other hills each having a height of not less than the height H (?m), and not including any hills having a height of more than 0.5H (?m) satisfy a specific relationship. Also, a surface layer of the charging member contains high-molecular compound particles whose average particle diameter is between 2 and 50 ?m and whose range of particle size distribution of average particle diameter is above 0?m and not greater than 7 ?m.

Abstract: In an image forming system, an image-bearing member having a photoconductor layer comprising an Si-based non-single crystal material is charged at a relatively low potential of 250 to 600 volts by a contact charging member in the presence of electroconductive fine powder. An electrostatic latent image formed on the image-bearing member is developed with a magnetic toner which includes magnetic toner particles comprising at least a binder resin and a magnetic iron oxide, and inorganic fine powder and electroconductive fine powder present at the surface of the magnetic toner particles. The magnetic toner has a weight-average particle size of 3-10 ?m and an average circularity of 0.950 to 0.995, and contains 0.05 to 3.00% of isolated iron-containing particles.

Abstract: An image forming apparatus includes an image bearing member capable of being rotated, a first charging unit, an electrostatic image forming unit, a developing unit, and a second charging unit. The first charging unit is capable of being rotated in the same direction as a rotational direction of the image bearing member with being in contact with the image bearing member, and is capable of charging the image bearing member and toner on the image bearing member. The electrostatic image forming unit is capable of forming an electrostatic image on the image bearing member charged by the first charging unit. The developing unit is capable of collecting the toner on the image bearing member and visualizing the electrostatic image.

Abstract: A charging apparatus has a movable image bearing member, a first charging member for charging the image bearing member, and a second charging member provided upstream of the first charging member with respect to the direction of movement of the image bearing member, the second charging member having an elastic rotary member rubbing against the image bearing member.

Abstract: The present invention provides an image forming apparatus which is small-sized and is able to keep a longtime and stable cleaning function. The image forming apparatus includes an image carrier; a blade member contacting elastically with the image carrier; a semi-conductive member installed on the blade member; and a power unit for adding a voltage to the semi-conductive member. Further, the semi-conductive member is set apart from the contacting portion of the blade member by a predetermined isolation distance.

Abstract: According to the present invention, in an image-forming apparatus having at least two chargers for charging a rotating image carrier, in accordance with change in bias applied to a second charger disposed on the downstream side in a rotational direction of the image carrier, the bias applied to a first charger disposed on the upstream side is changed. Thereby, the electric power required for the charging is reduced.

Abstract: A metering blade suspension system utilizes a leaf spring that performs multiple combined functions such as supporting a metering blade assembly, controlling the angle, position and/or load of the blade assembly while allowing the assembly to pivot in a quasi-frictionless motion, locking the blade assembly in place, providing an electrical connection and/or bleeding static charge.

Abstract: An image forming apparatus containing an image holding member, a contact-type charger for charging a surface of the image holding member, an exposure unit for forming an electrostatic latent image by exposing the charged surface of the image holding member, a developing unit for developing the electrostatic latent image with a spherical toner to obtain a toner image, and a transfer member for electrostatically transferring the toner image from the surface of the image holding member onto a transfer material. A number of toner particles remaining on the surface of the image holding member before passing through an abutting portion between the image holding member and the contact-type charger is in a range of 100 to 400 per unit area (mm2).

Abstract: A charging member electrically charges a member to be charged in a state that said charging member forms a nip with the member to be charged and electroconductive particles are present at the nip. The charging member includes an elastic foam member provided at a surface of said charging member. The elastic foam member includes cell portions and cell wall portions defining the cell portions. The cell wall portions have a thickness proportion to the cell portions of not less than 2% and not more than 40%.

Abstract: A cleaning device including a brush roller that contacts the surface of a charge roller for cleaning it and an image forming apparatus including the cleaning device are disclosed. The brush roller has a brush contacting the charge roller due to the weight of the brush roller. The brush roller rotates by following the rotation of the charge roller. The cleaning device has a simple configuration while the brush roller has high durability.

Abstract: A charging apparatus has a movable image bearing member, a first charging member for charging the image bearing member, and a second charging member provided upstream of the first charging member with respect to the direction of movement of the image bearing member, the second charging member having an elastic rotary member rubbing against the image bearing member.

Abstract: A charging member for charging a member to be charged and an image forming apparatus provided with the same have electrically conductive particles and an electrically conductive particle bearing member having elasticity and bearing the electrically conductive particles thereon, and the degree of cohesion of the electrically conductive particles is 0.1 to 85%. Thereby, the non-uniformity of a halftone image peculiar to particle charging can be improved.

Abstract: In a charging member having a support and provided thereon one or more cover layer(s), where the ten-point average surface roughness of the surface of the charging member is represented by Rz (&mgr;m), the height of a hill of the surface of the charging member is represented by H (&mgr;m), the area at the part of the hill is represented by Sa (&mgr;m2), and the area of a region surrounded by hills each having the height H (&mgr;m) and other hills each having a height of not less than the height H (&mgr;m), and not including any hills having a height of more than 0.5H (&mgr;m) is represented by Sb (&mgr;m2), these Ra, H, Sa and Sb satisfy a specific relationship.

Abstract: An image forming device is provided that is capable of easily preventing occurrence of stripe-like image noise that may be caused by intimate contact between a contact electrifying member and an image carrier even when an image forming operation is stopped for a while. In the image forming device having an electrifying roller in contact with a photoconductor, AC voltage is applied to the electrifying roller before the image carrier and the electrifying roller start rotating.

Abstract: An image forming apparatus of the present invention includes a movable body to be charged and a charger including a charging member that contacts or adjoins the body to be charged and applies a voltage, including an AC component, to the charging member for thereby charging the body. A protection substance for protecting the surface of the body from deterioration ascribable to charging is caused to exist on the body. The number of particular elements, contained in the protection substance and detected by an X-ray photon spectral analyzer (XPS) in a zone where the charging member charges the body, is held in a particular ratio to the total number of all elements constituting the outermost surface of the body and also detected by the XPS.