Abstract: An image forming apparatus includes: an image bearing body that is rotatable about a central axis thereof, and that bears a dot-like latent image, on a surface of the image bearing body, in each of a plurality of divided regions that are arranged in rows along a direction that intersects an axial direction of the central axis at a predetermined intersection angle; and a developer bearing roller that is rotatable in order to make visible, as a developer image, the dot-like latent images borne by the image bearing body, using a developer borne on a surface of the developer bearing roller, the developer bearing roller opposing the image bearing body such that an axial direction of the developer bearing roller is parallel to the axial direction of the image bearing body, and that includes a helical groove portion on the surface of the developer bearing roller, the helical groove portion being inclined at a predetermined inclination angle with respect to the axial direction of the developer bearing roller and bein

Abstract: An image forming apparatus is operable to form an image on a recording medium. An image carrier is adapted such that a toner image is formed thereon by developing an electrostatic latent image. An intermediate transfer member is adapted such that the toner image is primarily transferred thereto. In a transfer device, a roller member is adapted to come in contact with the intermediate transfer member. A first bias voltage applier is operable to provide a transfer voltage, thereby applying a first bias voltage between the roller member and the intermediate transfer member to secondarily transfer the toner image onto the recording medium in order to obtain the image. A charge eliminator is disposed in the vicinity of the roller member. A second bias voltage applier is operable to apply a second bias voltage to the charge eliminator to eliminate charges on the recording medium which has been subjected to the application of the first bias voltage.

Abstract: A developing device includes a toner particle-bearing roller that bears toner particles on its surface and develops a latent image borne by an image-bearing member with those toner particles, the toner particle-bearing roller has a projection portion disposed on its surface, the projection portion having a top surface having a flat portion, and a width of the top surface being equal to or more than a volume average particle diameter of the toner particles.

Abstract: An image forming apparatus including: a photoconductor, adapted such that an electrostatic latent image is formed thereon and extending in a first direction; and an optical scanner, operable to emit a light beam to expose the photoconductor while scanning in the first direction, wherein: the photoconductor and the optical scanner define a space therebetween; and the space allows air to flow therethrough in the first direction.

Abstract: A corona charger is provided with a back plate which defines a first space which surrounds a discharge electrode while opening a side that the discharge electrode faces an image carrier. The back plate is formed with a first opening. A storage has a second space which stores waste toner generated in the image forming apparatus. The storage is formed with a second opening. A filter causes ozone to pass through but blocks toner. The filter is disposed between the corona charger and the second space. The first space and the second space are communicated by way of the first opening and the second opening.

Abstract: A test pattern P3 longer than a length Ld corresponding to a circumferential length of a developing roller is formed along a moving direction of a photosensitive member (or developing roller). The developing roller transports a great quantity of toner on its surface in a first revolution thereof and hence, the test pattern has a high density. When the residual toner runs low, the toner transport quantity is decreased in the subsequent revolution, so that the test pattern P3 is decreased in the density at its portion beyond the length Ld from its head. If a density difference is observed at place corresponding to a boundary between image portions formed in the first revolution and the second revolution, it is concluded that image quality is degraded due to the shortage of residual toner.

Abstract: A corona charger is provided with a back plate which defines a first space which surrounds a discharge electrode while opening a side that the discharge electrode faces an image carrier. The back plate is formed with a first opening. A storage has a second space which stores waste toner generated in the image forming apparatus. The storage is formed with a second opening. A filter causes ozone to pass through but blocks toner. The filter is disposed between the corona charger and the second space. The first space and the second space are communicated by way of the first opening and the second opening.

Abstract: The present invention provides an electrophotographic dry toner comprising colored resin particles with releasing agent particles dispersed in a binder resin or an electrophotographic dry toner wherein a resin coating layer obtained by the fixation and fusion of encapsulating resin particles is provided on the surface of colored resin particles with releasing agent particles dispersed in a binder. The releasing agent particles dispersed in each colored resin particle have a particle diameter distribution such that the particle diameter of releasing agent particles dispersed in the vicinity of the surface of each colored resin particle is larger than the particle diameter of releasing agent particles at a central site of the colored resin particle. Alternatively, the colored resin particle is coated with the releasing coating layer with a releasing agent layer interposed between them.

Abstract: The present invention provides an electrophotographic dry toner comprising colored resin particles with releasing agent particles dispersed in a binder resin or an electrophotographic dry toner wherein a resin coating layer obtained by the fixation and fusion of encapsulating resin particles is provided on the surface of colored resin particles with releasing agent particles dispersed in a binder. The releasing agent particles dispersed in each colored resin particle have a particle diameter distribution such that the particle diameter of releasing agent particles dispersed in the vicinity of the surface of each colored resin particle is larger than the particle diameter of releasing agent particles at a central site of the colored resin particle. Alternatively, the colored resin particle is coated with the releasing coating layer with a releasing agent layer interposed between them.

Abstract: The present invention provides an electrophotographic dry toner comprising colored resin particles with releasing agent particles dispersed in a binder resin or an electrophotographic dry toner wherein a resin coating layer obtained by the fixation and fusion of encapsulating resin particles is provided on the surface of colored resin particles with releasing agent particles dispersed in a binder. The releasing agent particles dispersed in each colored resin particle have a particle diameter distribution such that the particle diameter of releasing agent particles dispersed in the vicinity of the surface of each colored resin particle is larger than the particle diameter of releasing agent particles at a central site of the colored resin particle. Alternatively, the colored resin particle is coated with the releasing coating layer with a releasing agent layer interposed between them.

Abstract: The present invention provides an electrophotographic dry toner comprising colored resin particles with releasing agent particles dispersed in a binder resin or an electrophotographic dry toner wherein a resin coating layer obtained by the fixation and fusion of encapsulating resin particles is provided on the surface of colored resin particles with releasing agent particles dispersed in a binder. The releasing agent particles dispersed in each colored resin particle have a particle diameter distribution such that the particle diameter of releasing agent particles dispersed in the vicinity of the surface of each colored resin particle is larger than the particle diameter of releasing agent particles at a central site of the colored resin particle. Alternatively, the colored resin particle is coated with the releasing coating layer with a releasing agent layer interposed between them.

Abstract: An automatic document conveyer comprising a moving frame turnably mounted on a machine housing via a hinge mechanism and a conveyer belt mechanism mounted on the moving frame. The conveyer belt mechanism includes a support frame, a drive roller and a driven roller arranged in the support frame, and a conveyer belt wrapped round the drive roller and the driven roller. The support frame of the conveyer belt mechanism is so supported as to be moved by a predetermined amount toward the side opposite to the hinge mechanism while the end of the conveyer belt on the side of the hinge mechanism reaches to the closed position after having come in contact with the transparent plate at the time when the moving frame is turned toward the closed position.

Abstract: Disclosed are a two-component type developer which is supplied to an area where a bias voltage of at least 250 V is applied, and a developing process using this developer. In this developer, by adjusting the particle size distribution of carrier particles within a specific range, occurrence of the so-called carrier dragging phenomenon of the transfer of the carrier together with the toner to a photosensitive material can be prevented. This adjustment of the particle size distribution is such that the content of carrier particles having a size smaller than 250 mesh is less than 8% by weight based on the entire carrier particles, the diameter D.sub.50 of the weight average particle size corresponding to 50% of the weight of the entire carrier particles is in the range of from 80 to 120 .mu.m and the difference between D.sub.25 and D.sub.75 is in the range of from 5 to 20 .mu.m.

Abstract: In accordance with the present invention, the electrophotographic toner is produced by dispersing and mixing toner components containing a fixing resin, a coloring agent and an electric charge controlling dye, and by melting and kneading the resulting mixture, which is then subjected to pulverizing and classifying. According to the present invention, fine powder generated at the pulverizing and classifying steps is reused as added to a mixture of toner components as already dispersed and mixed at the dispersing and mixing step, and the surface dye density of the electric charge controlling dye is in the range from 1.0.times.10.sup.-3 to 1.7.times.10.sup.-3 g/g, or the rate of the amount of an electric charge controlling dye present on the surfaces of toner particles to the total amount of the electric charge controlling dye, is in the range from 10 to 27% by weight.

Abstract: Disclosed is a two-component type developer comprising a toner and a coated magnetic carrier wherein said toner has an electroconductivity lower than 3.5.times.10.sup.-10 S/cm and the coating of said magnetic carrier consists of a silicone resin having as its component unit a basic nitrogen atom-containing organic group bonded to a silicone atom (N-containing silicone resin).Such developer is capable of forming images having a high image density and a high image quality, particularly as a white developer or a color developer if developing is carried out even under ordinary conditions, since the toner has its charge quantity maintained in an appropriate range in the developing step.

Abstract: Disclosed is a carrier of a developer, which is characterized in that the current value observed when a direct current is applied under a voltage of 200 V is 0.8 to 2.0 .mu.A and the relaxation time is in the range of from 4.0 to 6.0 milliseconds, that is, the characteristic values in the dynamic state, for example, in a developing apparatus, are kept with certain ranges. If this developer carrier is used, an image having a high quality can be obtained without occurrence of troubles often caused in conventional developers, such as carrier dragging (transfer of the carrier to a photosensitive material together with the toner), fogging (transfer of the toner to the background of a copying sheet) and letter thinning.