Abstract:
In a toner image fixing roller covered with a fluororesin layer, to evenly apply anti-offset agent to the roller surface and to increase sharpness of edge-portions of a toner image fixed on recording paper, a fixing roller consists of a core, elastic body layer and a fluororesin layer. The fluororesin layer contains filler (silicone oil or silicone powder) having affinity to anti-offset agent.
Abstract:
A fixing method for fixing an unfixed toner image formed on a recording material by transporting the recording material to a contact portion between a fixing roller and a pressurizing mechanism for pressurizing the surface of the fixing roller is arranged such that the fixing roller surface temperature and the pressurizing mechanism surface temperature at the contact portion while the recording material is being transported therethrough are controlled to fall within a non-offset region in which a sufficient fixing strength for fixing toner onto the recording material can be ensured without generating a high temperature offset, said non-offset region being defined by a critical border line obtained from a function of a fixing roller surface temperature and a pressurizing mechanism surface temperature. According to the described fixing method, an occurrence of an offset can be prevented without an application of an oil, and a toner fixing inferior can be prevented.
Abstract:
In a fixing device, a sheet of paper carrying an image formed with pre-fixed toner is transported to a fixing nip region in which (1) a fixing roller heated by a heating roller outside of the fixing roller and (2) a pressure roller come into contact, so that the toner is melted and fixed on the sheet of paper. The heating roller is controlled so that a surface portion of the fixing roller in the vicinity of an exit of the fixing nip region constantly has a set temperature during the transport of the sheet of paper through the fixing nip region. By thus arranging a fixing device, the resultant fixing device features a short warm-up period, high thermal efficiency and uniform temperature distribution, capability of fixing color toner without application of oil, durability and safety, a simple structure and a low manufacturing cost, no curling of paper after fixation, and applicability to high-speed printing.
Abstract:
A color image forming apparatus fixes a superimposed multi-color toner image, heat-fused at a heating section of an intermediate transfer belt, onto a recording material at a fixing nip section at which a pressing roller presses against the intermediate transfer belt. The fixing nip section is provided at the downstream end of the heating section in a turning direction of the intermediate transfer belt. The present apparatus can accelerate a fixing rate while maintaining stable fixing properties for a multi-layer toner image of a color image having different layer thicknesses with any kind of recording papers under any operation condition, and requires a shorter warm-up period while attaining excellent heat efficiency.
Abstract:
A developing device prevents deterioration of toner, i.e., prevent the toner from being damaged, or fused onto the blade, to realize a more reliable developing operation. In the developing device, an electron emitting section is provided onto the toner regulation blade in which apertures (151) are formed, wherein each of the apertures (151) is formed by electroforming to have an inner surface curved convexly to be widened outwardly to the side irradiated with an ultraviolet ray (shape A). Further, a photoelectric surface (152) is laminated on the surface of the electron emitting section with the apertures (151). With an application of ultraviolet ray onto the electron emitting section, the resulting photoelectrons as emitted from the photoelectric surface (152) are guided to the toner through the apertures (151). Here, for the aperture (151) of the shape A, a larger amount of electrons can be guided to the toner than the apertures in other shapes (B to E).
Abstract:
Light emitted from an entire surface of a light source is passed selectively through a liquid crystal shutter. The shutter can be controlled to open/close on a pixel basis in response to image data and then selectively passed light is converted into light having a specified wavelength by a nonlinear optical element before impinging on a metal film. The metal film induces and emits its own electrons and forms an electrostatic latent image directly on a dielectric film.
Abstract:
Toner attracted onto an electronic latent image formed on the surface of a photosensitive drum is transferred onto a transfer sheet, using a transfer bias from a transfer bias roller. A transfer belt for transporting the transfer sheet includes an anisotropic conductive layer composed of conductive members and an insulating member. The anisotropic conductive layer is conductive only in the thickness direction thereof and insulating in the other directions. This makes it possible to offer a transfer device that can prevent a transfer electric field from spreading and toner from being projected, and that boasts excellent sheet transportability.
Abstract:
The developing device X includes: toner T that contacts an electrostatic latent image on a photosensitive drum D; a charging roller 4 for charging the toner through contact; and an ultraviolet irradiator 5 for charging the toner by shining ultraviolet light onto a sleeve 41 of the charging roller from a position on the back of the sleeve 41 via a roller 42. The sleeve of the charging roller contains material that changes its molecular structure under ultraviolet irradiation by the ultraviolet irradiator in such a manner to charge the toner. Deterioration of a charged member (toner) can be prevented, and so is fusion of the charged member with the charging means. Reliability in the developing process proves.
Abstract:
A developing device for developing, by using a developer, a latent image formed on a surface of an image data forming member including a developer accommodating section for accommodating the developer; a first developer retaining member for receiving the developer from the developer accommodating section and transporting the developer; a second developer retaining member for receiving the developer from the first developer retaining member and making the developer adhere to the latent image formed on the image data forming member; a conductive member opposed to the second developer retaining member with an appropriate space interposed therebetween; a first voltage applying member for applying a voltage between the first developer retaining member and the second developer retaining member; a second voltage applying member for applying a voltage between the second developer retaining member and the surface of the image data forming member; and a third voltage applying member for applying a voltage between the second developer retaining member and the conductive member in order to form an electric field in the space therebetween.
Abstract:
A transfer roller device for transferring onto a copy paper sheet a full color toner image formed on an intermediate transfer belt. A rear-surface electrode roller disposed at the opposite side to a transfer roller with the intermediate transfer belt positioned in between, is divided into a plurality of cylinder members, and at least one of the cylinder members corresponding to the size of a copy paper sheet is separately connected to ground. With the arrangement, occurrence of an excess current through a portion of the intermediate transfer belt carrying no copy paper sheet thereon is eliminated, thereby preventing a filming phenomenon. In another arrangement, a plurality of rear-surface electrode rollers are disposed at respective positions associated with a plurality of respective copying speeds which are set according to copy paper sheets. Thus, a voltage to be applied between the transfer roller and the rear-surface electrode roller is maintained constant regardless of different copying speeds.