Abstract: Toner is for use in an image forming apparatus of the TonerJet method, which satisfies any one of the following conditions: a) toner in which the content of reverse-polarity large-diameter toner is 10% by count or smaller; b) toner in which the content of reverse-polarity fine-powder toner is 2% by count or smaller; c) toner comprising a silica additive and a titanium oxide additive such that the content x of the titanium oxide additive is in the range of 0<x?1.5 wt %. For instance, when an image is formed using toner satisfying the condition a) above, that is, toner in which the content of reverse-polarity large-diameter toner is 10% by count or smaller, filming does not occur and an image having an excellent quality is formed (denoted with “?”). On the other hand, when an image is formed using toner in which reverse-polarity large-diameter toner exceeds 10% by count, filming occurs and the quality of an image deteriorates (denoted with “X”).

Abstract: In a fixing device for causing a pressurizing roller to come in pressure contact with a heating roller including a central region heating heater for heating a central region and a side end region heating heater for heating a side end region on an outside of the central region, thereby fixing an unfixed toner, or an image forming apparatus comprising the fixing device, an outside of an image region of the heating roller is caused to have a peak of heat distribution of the central region heating heater and heat radiated from both side ends of the heating roller is compensated to flatten the temperature distribution of the image region, thereby preventing a deterioration in an image.

Abstract: The width of a spacer which defines a gap between a development roller and an FPC is set to the width of a toner layer which is carried on the development roller or narrower. This prevents an edge portion of the spacer from getting deformed. In addition, as the spacer is made of a material whose work function is approximately the same as the work function of toner, it is possible to suppress disturbance of a surface potential of the toner layer. Further, for the purpose of maintaining the uniformity of the toner layer, it is desirable to restrict the amount of the toner on the development roller to a predetermined value or smaller.

Abstract: In a writing head for forming an electrostatic latent image on a cylindrical image carrier, a plurality of writing electrodes are arranged on a first face of a film substrate in a first direction parallel with an axial direction of the image carrier. The writing electrodes are adapted to be abutted against an outer periphery of the image carrier to provide electric charges thereto. A first wiring member are arranged on the first face of the film substrate to supply signals from a first electrode driver to a first electrode group in the writing electrodes. A second writing member are arranged on a second face of the film substrate to supply signals from a second electrode driver to the second electrode group in the writing electrodes.

Abstract: A belt member is formed with a seam portion by overlapping and adhering both longitudinal end portions thereof to constitute an endless belt stretched and circulated by a rotative, first stretching member and a second stretching member. A length of the seam portion is no less than a length between a first point at which the endless belt is separated from one of the first stretching member and the second stretching member and a second point at which the endless belt is brought into contact with the other one of the first stretching member and the second stretching member.

Abstract: Toner is for use in an image forming apparatus of the TonerJet method, which satisfies any one of the following conditions: a) toner in which the content of reverse-polarity large-diameter toner is 10% by count or smaller; b) toner in which the content of reverse-polarity fine-powder toner is 2% by count or smaller; c) toner comprising a silica additive and a titanium oxide additive such that the content x of the titanium oxide additive is in the range of 0<x≦1.5 wt %. For instance, when an image is formed using toner satisfying the condition a) above, that is, toner in which the content of reverse-polarity large-diameter toner is 10% by count or smaller, filming does not occur and an image having an excellent quality is formed (denoted with “◯”). On the other hand, when an image is formed using toner in which reverse-polarity large-diameter toner exceeds 10% by count, filming occurs and the quality of an image deteriorates (denoted with “X”).

Abstract: The width of a spacer which defines a gap between a development roller and an FPC is set to the width of a toner layer which is carried on the development roller or narrower. This prevents an edge portion of the spacer from getting deformed. In addition, as the spacer is made of a material whose work function is approximately the same as the work function of toner, it is possible to suppress disturbance of a surface potential of the toner layer. Further, for the purpose of maintaining the uniformity of the toner layer, it is desirable to restrict the amount of the toner on the development roller to a predetermined value or smaller.