Abstract: An apparatus and method for non-interactive, dry powder development of electrostatic images includes an image bearing member bearing an electrostatic image; two component developer comprising toner and permanently magnetized thickly coated carrier beads, the coated carrier beads having magnetizable core radius r, average radius a, and magnetization Mb, with the ratio r/a being given as K; a developer transporting member having a thickness t for transporting a developer layer of the two component developer, wherein the layer is spaced close to and out of contact with the image bearing member, a multipole magnet member disposed in close proximity to the transporting member and moving relative to it so as to sweep poles across its surface, the magnet member having a periodic magnetization of spatial frequency k and a peak magnetization M0 wherein Mb, t, k, and M0, are chosen such that Mb is sufficiently large to prevent the escape of developer, a quantity C in the equation 1 C = 2.

Abstract: A method of forming an image includes causing a material, that increases a viscosity of liquid drops by contact with the liquid drops, to adhere to a transfer medium, causing a liquid drop to contact the material according to an image signal such that an image is formed with the liquid drop having been increased in viscosity by contact with the material, and transferring the image to a recording medium. The viscosity of the liquid drop when increased on the transfer medium by contact with the material is set such that the liquid drop adheres to the recording medium without being divided into a part remaining on the transfer medium and another part being transferred to the recording medium. By the above-described image forming method, good image transfer is realized and thereby an image having no blotting is obtained.

Abstract: An image forming apparatus of the present invention includes a developing device including a rotatable, nonmagnetic developer carrier and a magnetic field forming device. In a developing region where the developer carrier faces an image carrier, the magnetic field forming device causes a developer made up of toner and magnetic grains to rise on the developer carrier in the form of a magnet brush. In the developing region, the magnet brush on the developer carrier is caused to move at a higher speed than the surface of the image carrier in the same direction as and in contact with the surface of the image carrier, thereby developing the latent image. The toner of the developer is magnetic toner. Flux density set up in the developing region outside of the surface of the developer carrier in a normal direction has an attenuation ratio of 50% or above.

Abstract: An image forming apparatus includes a housing, a toner hopper, a toner supply source, a magnetic roller, a development sleeve, a doctor blade, an agitator, a rotation arm provided in the agitator, a spoon formed on the tip of the rotation arm, a toner shelf arranged immediately below the development sleeve, a developer returning member provided between the doctor blade and the toner hopper, and a weir for guiding the toner and magnetic carrier cut and removed when the developer returning member returns the toner to the toner shelf. The weir has a top portion equal to or higher than the spoon surface when the rotation arm is horizontal. A space for passing through toner is formed between the weir and the developer returning member.

Abstract: An image forming apparatus comprises a housing, a toner hopper, a toner supply source, a magnetic roller, a development sleeve, a doctor blade, an agitator, a rotation arm provided in the agitator, a spoon formed on the tip of the rotation arm, a toner shelf arranged immediately below the development sleeve, a developer returning member provided between the doctor blade and the toner hopper, and a weir for guiding the toner and magnetic carrier cut and removed when the developer returning member returns the toner to the toner shelf. The weir has a top portion equal to or higher than the spoon surface when the rotation arm is horizontal. A space for passing through toner is formed between the weir and the developer returning member.

Abstract: In order to provide an image forming apparatus capable of forming a quality image by restricting a distance between a developing roll and a magnetic roll with a simple structure, an image forming apparatus comprises a magnetic roll 1 and a developing roll 2 that are disposed in parallel with a predetermined distance and a developing unit 50 that develops an electrostatic latent image on a photosensitive body drum 3 disposed on the image forming apparatus main body using a toner thin layer formed on the surface of the developing roll by means of the magnetic roll, wherein a member for holding rotational axes having a pair of openings for holding, which fits and holds rotatably and integrally each of rotational axes of the magnetic roll and the developing roll is provided, the opening for holding of the developing roll being capable of swinging around the axis center of the opening for holding of the magnetic roll.

Abstract: There is disclosed a developing device including a toner hopper, a toner supply source, a toner table on which a toner is laid, an agitator for carrying the toner to the toner table from the toner hopper, a magnet roller disposed above the toner table, a developing sleeve which covers an outer periphery of the magnet roller, holds a magnetic carrier, allows the toner of the toner table to be adsorbed onto the magnetic carrier, and shifts and attaches the toner to an electrostatic latent image of a photosensitive drum, a doctor blade disposed close opposite to the developing sleeve, and a developer returning member which is disposed between the developing sleeve and the toner hopper and is positioned in a position higher than a position of the toner table to prevent the toner cut/removed by the doctor blade from dropping toward the toner hopper and to return the cut/removed toner to the toner table, and which has a tip end displaced toward the developing sleeve from the boundary of the toner table and the tone

Abstract: A toner maintenance system for an electrophotographic developer unit, including a sump for storing a quantity of developer material comprised of carrier and toner material; a first member for transporting a mixture of developer material and toner particles from the sump, the first member having a voltage applied thereto; a metering blade, positioned closely adjacent to the first member to maintain the compressed pile height of the developer material on first member at a desired level; and a sensor device for measuring the current between the first member and the metering blade, and generating a signal indicative thereof.

Abstract: The invention relates generally to apparatus for electrostatic image development and, in particular, apparatus that implement a magnetic brush with a drum photoconductor. According to an aspect of the invention, a method and apparatus for developing an electrostatic image are provided implementing a drum photoconductor and a magnetic brush contacting the drum photoconductor. The magnetic brush includes a mixture of toner and hard magnetic carriers.

Abstract: A two-component developer unit of an electrophotographic image forming apparatus includes a developer rectifier having a lifting guide portion and a developer collection guide portion. The lifting guide portion guides a developer agitated by an agitating unit upward along a circumferential direction of a developer magnet roller. The developer collection guide portion keeps the developer to move down to the lifting guide portion between a developer blade and the lifting guide portion. A non-uniformity of image intensity can be solved without giving an overweight load to the developer and a photoreceptor and without increasing a driving torque of the developer and the photoreceptor.

Abstract: An image forming apparatus of non-contact developing method using two-component developer material which is capable of obtaining a clear image free from fogging, ghost and toner contamination. The image forming apparatus has at least one developing unit which develops an electrostatic latent image on a photosensitive body with a toner thin layer formed on the surface of a developing roll wherein a toner thin layer forming region on the developing roll is smaller than a magnetic brush forming region on the magnetic brush.

Abstract: When image formation is performed by an apparatus comprising: a magnetic roll for generating a magnetic brush by carrier having toner adhering triboelectrically thereto, a developer roll on the surface of which a thin layer of the toner supplied by the magnetic brush is formed, and a photoreceptor onto which the toner of thin layer jumps selectively in accordance with the latent image thereon; positively chargeable toner of which charge amount is controlled in 5˜20 &mgr;C/g is used, the surface potential of the photoreceptor is set to a range above 0 to 250 V, and the after exposure potential which is the potential right after the photoreceptor is exposed is in a range of 0˜ to 100 V.

Abstract: A developing device for feeding a developer stored therein to an image carrier of the present invention includes a sleeve facing the image carrier for causing the developer deposited thereon to contact a latent image formed on the image carrier. A regulating member faces the sleeve for regulating the thickness of the developer that forms a layer on the sleeve. A guide member has a guide surface for guiding the developer regulated by the regulating member toward the surface of the image carrier. The guide surface has a conductive surface facing the sleeve. The developing device protects the image carrier from defective images ascribable to impurities, which include deteriorated toner and paper dust, without resorting to a filter mechanism or a bias for collection.

Abstract: A developing device for an image forming apparatus includes a developing roller for conveying toner deposited thereon to a developing region where it faces a photoconductive element. A magnet brush roller conveys a two-ingredient type developer, which consists of toner and magnetic particles, deposited thereto to a toner supplying region where it faces the developing roller. In the toner supplying region, only the toner is supplied from the magnet brush roller to the developing roller. The distribution of the number of toner particles for an amount of charge differs from the developing roller to the magnet brush roller.

Abstract: A developing device of an image forming apparatus using a two-component developer including toner and carrier includes a developer stirring device to stir the developer to change the toner of the developer, a developing sleeve to rotate and to carry on its surface the developer, and a conductive doctor blade or configured to regulate a thickness of the developer on the developing sleeve. The doctor blade is either grounded or receives a voltage of an electric polarity opposite to that of the toner. An electric potential of the developing sleeve is set to a same electric polarity as that of the toner, and the toner is moved toward a latent image formed on a photoconductor of the image forming apparatus so as to adhere to the latent image by an electric field formed between the developing sleeve and the latent image on the photoconductor.

Abstract: A device and method for inking a charge pattern of a carrier medium. The device includes a toner sprayer that generates and directs a mixed toner stream onto a surface of an application element. The mixed toner stream includes a number of charge toner and air particles and forms a toner layer when the mixed toner stream contacts the application element surface. The application element is movably positioned in close proximity to the carrier medium for transferring the charged toner particles onto the charge pattern of the carrier medium for inking the same.

Abstract: When image formation is performed by an apparatus comprising: a magnetic roll for generating a magnetic brush by carrier having toner adhering triboelectrically thereto, a developer roll on the surface of which a thin layer of the toner supplied by the magnetic brush is formed, and a photoreceptor onto which the toner of thin layer jumps selectively in accordance with the latent image thereon; positively chargeable toner of which charge amount is controlled in 5˜20 &mgr;C/g is used, the surface potential of the photoreceptor is set to a range above 0 to 250 V, and the after exposure potential which is the potential right after the photoreceptor is exposed is in a range of 0˜ to 100 V.

Abstract: A development apparatus includes a toner carrying member for carrying magnetic toner disposed opposed to an image bearing member to form a developing zone: magnetic field generating means in the toner carrying member; a toner supplying rotary member for applying the magnetic toner onto the toner carrying member and stripping the magnetic toner from the toner carrying member, comprising a surface layer of electrically conductive foam material.

Abstract: In a developing system containing a combination of forward-rotating and a backward-rotating developing rollers, a steady quantity of developing agent should be supplied to the developing rollers for high-quality printed images. This requirement can be satisfied by placing a doctor blade between an intersection point, where a line connecting the central axis of one of the developing rollers and its polarity reversing position meets a line connecting the central axis of the other of the developing rollers and its polarity reversing position, and the developing roller pair.

Abstract: An object of the present invention is to provide a developing apparatus which can obtain a stable toner charging amount even if a developer charging member is contaminated by toner and reduce reversal fog to reduce toner consumption, and which has a developer carrying body for carrying a developer to a developing position, and a developer charging member contacted with the developer to charge the developer, wherein the developer includes toner and conductive particle.

Abstract: A developing device comprises a developer bearing member for bearing and conveying a developer having a toner and a carrier, a first magnetic pole arranged in the developer bearing member, a second magnetic pole arranged in the developer bearing member, a polarity of the second magnetic pole being opposite to a polarity of the first magnetic pole, and the second magnetic pole being adjacent to the first magnetic pole and arranged on a downstream side of the first magnetic pole in a moving direction of the developer bearing member, a regulating member for regulating a layer thickness of the developer borne by the developer bearer, the regulating member being arranged in the vicinity of the second magnetic pole and a concentration detector for detecting a concentration of the toner in the developer.

Abstract: The invention relates generally to processes for electrostatic image development, and setpoints that provide uniform image development. In particular, an apparatus and process having a magnetic brush that implements hard carriers and a rotating magnetic core within a shell is disclosed. The process implements one or more of the following optimum setpoints: a range of shell surface speeds that provide uniform toning density, a range of shell surface speeds that prevent toner plate-out, a skive spacing that minimizes sensitivity to variation, a magnetic core speed that minimizes sensitivity to variation, and an imaging member spacing that minimizes sensitivity to variation.

Abstract: A developing apparatus in which a developer borne on a developer bearing body contacts an image bearing body at a developing portion. The developer is provided in a noncontact manner in the form of a developer cloud to the developer bearing body.

Abstract: A developing device for an image forming apparatus includes a developing roller for conveying toner deposited thereon to a developing region where it faces a photoconductive element. A magnet brush roller conveys a two-ingredient type developer, which consists of toner and magnetic particles, deposited thereto to a toner supplying region where it faces the developing roller. In the toner supplying region, only the toner is supplied from the magnet brush roller to the developing roller. The distribution of the number of toner particles for an amount of charge differs from the developing roller to the magnet brush roller.

Abstract: The present invention provides for a developing device comprising a developing roller configured to supply developer to a developing portion, a first conveying path configured to guide a moving of the developer and from which the developer is supplied by the developing roller to the developing portion, a first mixer configured to mix the developer while the developer is moving along the first conveying path, a second conveying path configured to guide the moving of the developer, wherein a residual developer left on the developing roller is recovered to the second conveying path and conveyed to the first conveying path, a second mixer configured to mix the developer while the developer is moving along the second conveying path, and a partition member arranged between the developing roller and the first conveying path to prevent leakage of the developer from between the developing roller and the first conveying path to the second conveying path directly, wherein one end of the partition member is brought in co

Abstract: An image forming apparatus according to the present invention has a developing roller which supplies a developer to a developing target, a housing which contains the developer, a developer agitating member which is rotated about a rotation center defined at a predetermined position in the housing and below a rotation center of the developing roller in the vertical direction, a table-like area which is defined at a predetermined position in the housing and temporally supports the developer material moved between the developing roller and the developer agitating member, and a developing apparatus included of a projective member for controlling the amount of the developer which is supplied onto the outer circumference of the developing roller.

Abstract: When the structure is arranged such that one of the repulsion poles is used as a developer layer thickness regulation pole, screw pitch-shaped density unevenness occurred at the rear end of a solid black image.

Abstract: The developing device of the present invention includes a developing magnet roller to supply developer to images to be developed, a first conveying auger arranged with a specified gap provided between the developing magnet roller to convey developer while stirring in the first longitudinal direction and supply developer to the developing magnet roller and a second conveying auger provided below the first conveying auger to receive developer conveyed from the first conveying auger and convey this received developer while stirring in the second longitudinal direction that is reverse to the first longitudinal direction and convey developer by circulating between the first conveying auger. This developing device further includes a housing to house the first conveying auger and developer so as to uniformly supply it to the developing magnet roller along the longitudinal direction irrespective of the developer accumulate height along the longitudinal conveying direction by the first conveying auger.

Abstract: A developing unit of the present invention includes a case which accommodates toner containing pigment, a developing roller, a supply roller having chamfered ends and formed of an elastic member arranged to be pressed against a surface of the developing roller in such a manner as to supply toner to the surface of the developing roller. Moreover, the ratio or open cells in the elastic supply roller is made to be 30% or higher and depth of engagement of the supply roller to the developing roller is made to be 0.4 mm or smaller. Also a first sealing member is disposed on the side ends of the developing roller and supply roller so as to prevent leakage to the outside portion of the case. The side surfaces of the developing roller have a surface roughness of 0.5 &mgr;m or smaller in Rmax.

Abstract: The invention provides a developing apparatus which prevents transportation of aggregated toner powder to an image carrier and thereby assures a high print quality by taking a countermeasure to disperse aggregated toner powder when development of an image carrier with developer which includes toner powder and magnetic powder is performed. The developing apparatus includes a developing roller, a developer control member, and an aggregated toner dispersion member disposed in an opposing relationship to the transport magnetic pole of the fixed magnet on the upstream side with respect to the position of the developer control member and having a contact face in the form of a flat face with which the developer held on the outer circumferential face of the developing roller may be contacted under pressure in order to disperse aggregated toner powder in the developer held on the outer circumferential face of the developing roller.

Abstract: A printer or copier has a developer station for a toner image wherein a photoconductive drum is provided with a latent charge image that is developed by applying a toner/air mixture to a developer drum that in turn applies the toner to the photoconductive drum. The toner is charged by a charging device as it is applied to the developer drum. A sensor senses the toner on the developer drum and a control varies the quantity of toner applied. The sensor is an optical sensor or a capacitive sensor, and the charge applied to the toner by the charging device is varied depending on the sensor output. A voltage applied to the developer drum may also be varied.

Abstract: An image-forming method uses an assembly having a first toner replenishing hopper, a toner storage room, a nonmagnetic cylindrical rotating member provided with a first mixed magnetic field-generating device, a first magnetic blade, a nonmagnetic cylindrical development sleeve provided with a second fixed magnetic field generating device, a second magnetic blade, an electrostatic image holding member, a cleaning device and a second toner-replenishing hopper. At least certain of the foregoing components are set to have specific positional relationships with one another so that the recovered magnetic toner is efficiently reused together with the fresh magnetic toner.

Abstract: A developing apparatus of an electrophotographic apparatus includes a housing for accommodating a developer, first, second and third developing rollers are rotatably disposed in the housing and arranged opposite to a photoconductor drum for conveying a developer carried on respective surfaces of the developing rollers, and a conveyor roller rotatably disposed in the housing for conveying the developer carried on a surface thereof to one of the developing rollers. First and second screw conveyors are disposed in the housing for conveying the developer in an axial direction opposite to each other. Each of these conveyors has an axial length larger than an axial length of the developing rollers. A partition wall is disposed between the first and second screw conveyors. A toner container for accommodating a toner is mounted on the housing. The toner in the toner container is supplied into the housing and agitators agitate the toner in the housing.

Abstract: A developing device having a reduced size in the horizontal direction and in which a developing agent is transported with stirring along a circulating route inside a developing tank to effectively mix newly added toner therewith and stir the mixture. A developing tank for storing developing agent therein is horizontally divided with a partition member thereby providing an upper chamber and a lower chamber. A developer roller and a stirring roller are disposed in the lower chamber. Two screw rollers are disposed in the upper chamber. An inlet opening is formed between an end of the partition member and a regulating member for restricting a layer if the developing agent adsorbed to the developing roller. A developing agent removed by the restricting member is fed through an inlet opening to the screw rollers in the upper chamber. The developing agent is mixed with fresh toner supplied through a supply inlet and transported with being stirred by the screw roller in its axial direction.

Abstract: In a developing device comprising a developing member for transferring toner onto an electrostatic latent image for visualization, and a developer supplying member for magnetically attracting two-component developer on the peripheral surface for conveyance, and supplying two-component developer or toner to the developing member, the developer will be sufficiently agitated on the developer supplying member, and toner density and amount of toner charge in the two-component developer will be controlled with simple structure. A part of two-component developer, to which toner has been supplied on the developer supplying member, is caused to flow back on the upstream side in the conveying direction within a range in which the attracting force of magnetic poles of the internal member which the developer supplying member has acts.

Abstract: A developing apparatus is provided for incorporation into an image forming machine. The developing apparatus includes a developer accommodating space for containing a developer composition, a series of developing rollers disposed in the developer accommodating space adjacent to each other and in facing relationship to an electrostatic latent image carrier for supplying the developer composition to the image carrier while transferring the developer composition from one developing roller to another, and a developer feed regulator for regulating the transfer of the developer composition between adjacent two of the developing rollers.

Abstract: An apparatus for developing an electrostatic latent image includes a first developing agent application device and a second developing agent application device disposed facing the peripheral surface of a photosensitive material drum, a developing agent stirring/conveying mechanism for conveying the developing agent to the first developing agent application device, a magnetic conveyer disposed at the back of the second developing agent application device, and a developing agent return guide plate for sending the developing agent conveyed by the magnetic conveyer to the side of the developing agent stirring/conveying mechanism. The second developing agent application device is provided with a developing agent-peeling zone where magnetic poles of the same polarity are magnetized neighboring each other on the upstream side of the position which is closest to the sleeve member of the magnetic conveyer in the direction of rotation.

Abstract: In a development device for developing an electrostatic latent image formed on an image bearing body, the development device includes: a developer bearing body for conveying a developer borne thereon to a developing area on the image bearing body; a plurality of magnetic poles provided inside the developer bearing body; a detaching magnetic pole including optional two adjoining poles of the plurality of magnetic poles which are arranged to have the same polarity as each other for forming a repulsive magnetic field to remove the developer on the developer bearing body; and a magnetic body provided in the vicinity of and spaced away from the detaching magnetic pole, for forming a repulsive magnetic field having the same polarity as that of the detaching magnetic pole.

Abstract: A developing method for an image formation system includes the steps of supplying a toner and developing an electrostatic latent image formed on a latent image support of the image formation system with the toner for visualization. A toner amount of a solid area T(g/m.sup.2) has a maximum toner amount per unit area on a recording medium and satisfies the following expression:1.ltoreq.T/a.ltoreq.1.2wherein a=(4.pi./3).multidot.(dt/2).sup.3 .multidot..rho.t({(3).sup.1/2 .multidot.dt.sup.2 /2} (g/m.sup.2), where dt is a toner volume center diameter (m) and st is a toner density (g/m.sup.3). A developing device for developing an electrostatic latent image includes toner amount regulation means for regulating a toner amount that satisfies the above expression.

Abstract: A developing unit of the present invention includes a developing roller facing a photoconductive element and formed with a magnetic layer on its circumference. The magnetic layer has a plurality of magnetic poles of opposite polarities alternating with each other and each extending in the axial direction of the developing roller. A developer consisting of magnetic particles an toner are deposited on the developing roller by the magnetic poles and conveyed by the roller to the photoconductive element carrying a latent image thereon, thereby developing the latent image. An agitator for agitating the magnetic particles and toner is positioned relative to the developing roller such that a blade thereof has an agitation range overlapping with the magnetic force range of the magnet layer. With this configuration, it is possible to insure high quality images free from background contamination and toner scattering while extending the service life of the developing unit.

Abstract: An apparatus and method for non-interactive, dry powder development of electrostatic images including: an image bearing member bearing an electrostatic image; two component developer including toner and permanently magnetized carrier beads, the carrier having average diameter (2a) and magnetization M.sub.b a developer transporting member having a thickness t for transporting a developer layer of the two component developer, the layer spaced close to and out of contact with the image bearing member, and wherein the developer layer is substantially without chains of carrier beads, a multipole magnet member disposed in close proximity behind the transporting member and moving relative to it so as to sweep poles across its surface, the magnet member having a periodic magnetization of spatial frequency k and a peak magnetization M.sub.0wherein M.sub.b, t, k, and M.sub.0, are chosen such that M.sub.b is sufficiently large to prevent the escape of developer, and a quantity ##EQU1## is greater than about 1/3.

Abstract: A developing unit having a device that constantly regulates the toner density supplied to the developing roll by using an elastic member that is installed in a passage between a reservoir chamber and the regulator chamber. The elastic member causes the pressure throughout the developing unit to remain more even despite the force generated by the agitator located in the reservoir chamber. Thus, the density of toner on printed images is more constant, blockages in the developing unit are reduced, and the quality of printed images are improved.

Abstract: There are disclosed a foamed rotary member having a surface of a foam, and a large number of cells provided in the foam and each having a prolate spheroid shape, wherein the major axis direction of the cell is along the rotation axis direction, and also a developing device using the foamed rotary member as a toner supplying rotary member.

Abstract: A developing unit includes a housing enclosing a mesh belt stretched across first and second rollers. The belt passes between a pair of friction plates that can be used to tribocharge toner particles carries on the mesh belt. Charging occurs over the large width of the entire mesh belt and the friction plates. Toner is transported on the surface of the mesh belt to a developing roller which, in turn, transports the toner to the surface of a photoconductor. The configuration of this developing unit reduces the loading associated with the tribocharging operation and the belt transport system reduces the volume of the developing unit.

Abstract: A toner cartridge of a laser printer, copier or facsimile machine has various strips in it for various functions. Among the strips are recovery blades, spreader blades, wiper blades, certain shipping seals, doctor blades and other miscleaneous strips. A device and method is shown that enables any strip or modular shipping seal to be ergonomically installed in a userfriendly way by leaving a strip of protective liner protruding from the strip for easy removal. Also, a device and method for attachment of strips is shown that utilizes a positioning tab stiffener device for userfriendly easy insertion of said strip into a toner cartridge, laser printer, copy cartridge or facsimile machine. After the positioning tab is used to install the strip, the positioning tab stiffener device is removed from the strip assembly. By using preferential 2-sided tapes or transfer tapes that are removable on one surface, the positioning device tab may be removed easier.

Abstract: A developing unit having a frame mounted in an electrophotographic apparatus with a photosensitive drum uses an agitator agitating toner contained in a toner receptacle of the frame of the developing unit, a developing roll for developing a latent image formed on the surface of the photosensitive drum with the toner, at least one toner supply roll with a cross-shaped blade mounted on a shaft for supplying the agitated toner to the developing roll, and a doctor blade for regulating the thickness of the toner layer formed on the toner developing roll so that the thickness of the toner layer is maintained at a given level. Each branch of the cross-shaped blade is tapered toward an outer end at a given angle so as to properly supply the toner to the developing roll.

Abstract: In an image forming apparatus, a developing device operable with toner or single component type developer has a hard first developing roller and a soft second developing roller. Fine magnetic N-S poles are formed on the periphery of the first roller. The second roller conveys the toner, electrostatically transferred thereto from the first roller, to an image carrier. The device frees a toner image from deterioration due to toner particles charged to a polarity opposite to an expected polarity. The toner forms a uniform thin layer on the first roller and is uniformly charged. Toner for use with this type of developing device is also disclosed.

Abstract: In a developing apparatus, a developing roller has a toner layer formed on a surface thereof, which toner layer is brought into contact with a photoconductor. A magnetic conveying roller having a magnet body is arranged rotatively close to the photoconductor. A regulating plate is provided at an outer periphery of the conveying roller.

Abstract: A development device of this invention includes a developer carrier for transporting a developer to a development region opposite to an image bearing body as binding the developer thereto by means of a magnetic force, and a regulating member opposing the developer carrier across a required distance therebetween and regulating the amount of developer transported by the developer carrier to the development region, the regulating member having a greater roughness at its surface opposite to the developer carrier than the developer carrier.

Abstract: A developing apparatus forms multiple toner layer and stably obtains predetermined toner charging amount and toner layer thickness, and further uniformly supplies the toner onto the toner carrying roller along its entire length. In the developing apparatus, a brush-like toner supplying roller having brush fibers and a second toner supplying roller are disposed at a predetermined interval and respectively brought into contact with a developing roller. The brush-like roller is first brought into contact with the developing roller after passing through the developing area on a photosensitive body opposing thereto, and the brush-like roller rotates in an inverse rotational direction to that of the developing roller at the contact position. The second roller is brought into contact with the developing roller after passing through the contact position with the brush-like roller, and rotates in a same rotational direction as that of the developing roller at the contact position.