摘要:
In a method and apparatus for developing a latent electrostatic image formed on the surface of an image-bearing material by applying a powdery developer thereto, which includes magnetically retaining a layer of a relatively conductive one-component developer having a resistivity of not more than 10.sup.13 ohms-cm on the surface of a developer-retaining member, and bringing the developer on the surface of the developer-retaining member into contact with the surface of the image bearing material, the improvement wherein the developer-retaining member has a resistance, measured by a point-plane resistance measuring method in an environment kept at a temperature of 20.degree. C. and a humidity of 50%, of from 3.times.10.sup.7 ohms to 1.times.10.sup.10 ohms. The improved method makes possible good development without causing a background fog or a tail effect.
摘要:
An electrostatic copying apparatus has a housing having at its top surface a transparent plate on which to place an original to be copied, a rotary drum disposed within the housing and having a photosensitive member on its surface, a charging, a developing, a transferring and a cleaning mechanism which are successively arranged around the rotary drum in the moving direction of its surface, an optical system for projecting the image of the original onto the surface of the rotary drum between the charging means and the developing means, and a receptor sheet conveying system for transferring a receptor sheet through a transfer station defined between the surface of the rotary drum and the transferring mechanism. A support is mounted on the housing so that it is slidable in the forward and rearward directions between its operating position within the housing and its pulled-out position ahead of the housing, and the rotary drum and the developing device are mounted on the support so that they can be separately and independently detached from the support. An electrostatic copying process can be efficiently practiced by using this apparatus.
摘要:
An electrophotograhic copying process forms an electrostatic latent image on the surface of a photosensitive member, developes the image by applying a monocomponent developer to the latent image to form a toner image, transfers the thus formed toner image by contacting a receptor sheet with the photosensitive member to transfer the toner image to the surface of the receptor sheet, fixes the toner image onto the surface of the receptor sheet, eliminates electrostatic charge from the photosensitive member by irradiating the surface of the photosensitive member with an electrostatic eliminating lamp after the toner image has been transferred to the receptor sheet, and cleans the surface of the photosensitive member by removing the developer remaining on the surface thereof. A developer-holding member holds the same kind of developer as used in the developing step on the surface of said developer-holding member by a stationary magnet disposed within the developer-holding member, and the surface of the developer-holding member is moved in a direction opposite to the direction of movement of the surface of the photosensitive member while contacting the two surfaces through the layer of the developer to mechanically brush the surface of the photosensitive member by the layer of the developer. The magnet having a plurality of poles, and the magnetic pole which is located closest to a position at which the surface of the developer-holding member is closest to the surface of the photosensitive member is downstream in the rotation direction of the developer-holding member by a certain angle with respect to the position at which the two surfaces are closest to each other.
摘要:
An electrostatic copying apparatus has a housing having at its top surface a transparent plate on which to place an original to be copied, a rotary drum disposed within the housing and having a photosensitive member on its surface, a charging, a developing, a transferring and a cleaning mechanism which are successively arranged around the rotary drum in the moving direction of its surface, an optical system for projecting the image of the original onto the surface of the rotary drum between the charging mechanism and the developing mechanism, and a receptor sheet conveying system for transporting a receptor sheet through a transfer station defined between the surface of the rotary drum and the transferring mechanism. A support is mounted on the housing so that it is slidable in the forward and rearward directions between its operating position within the housing and its pulled-out position ahead of the housing, and the rotary drum and the developing device are mounted on the support so that they can be separately and independently detached from the support. An electrostatic copying process can be efficiently practiced by using this apparatus.
摘要:
An electrostatic copying apparatus has a housing having at its top surface a transparent plate on which to place an original to be copied, a rotary drum disposed within the housing and having a photosensitive member on its surface, a charging, a developing, a transferring and a cleaning mechanism which are successively arranged around the rotary drum in the moving direction of its surface, an optical system for projecting the image of the original onto the surface of the rotary drum between the charging means and the developing means, and a receptor sheet conveying system for transferring a receptor sheet through a transfer station defined between the surface of the rotary drum and the transferring mechanism: A support is mounted on the housing so that it is slidable in the forward and rearward directions between its operating position within the housing and its pulled-out position ahead of the housing, and the rotary drum and the developing device are mounted on the support so that they can be separately and independently detached from the support. An electrostatic copying process can be efficiently practiced by using this apparatus.
摘要:
A transfer film comprising a transparent plastic film substrate, an undercoating layer composed of an electrically conductive resin and having a surface resistance of 1.0.times.10.sup.6 to 9.0.times.10.sup.9 .OMEGA., and a toner receiving layer composed of a binder resin and having a surface resistance of 1.0.times.10.sup.10 to 1.0.times.10.sup.14 .OMEGA., which is formed on at least one surface of the transparent plastic film substrate through the undercoating layer.
摘要:
A corona discharge device including a corona discharge electrode, an opposing electrode disposed opposite to the corona discharge electrode, a high voltage alternate current source electrically connected between the two electrodes, and a grid provided in a corona discharge current flow path between the two electrodes. The grid is grounded through a nonlinear bias element.
摘要:
Disclosed is a method for preparing an original for projection by using a transfer film comprising a transparent plastic film substrate, an undercoating layer composed of an electrically conductive resin and having a surface resistance of 1.0.times.10.sup.6 to 9.0.times.10.sup.9 .OMEGA., and a toner receiving layer composed of a binder resin and having a surface resistance of 1.0.times.10.sup.10 to 1.0.times.10.sup.14 .OMEGA., which is formed on at least one surface of the transparent plastic film substrate through the undercoating layer.An original for projection which is excellent in the surface smoothness and image characteristics can be obtained by electrostatically transferring an image of a one-component type magnetic developer on a photosensitive plate for the electrostatic photography, onto the toner receiving layer of the above transfer film and bringing the transferred developer image into contact with a roller under application of a pressure to fix the developer image on the toner receiving layer.
摘要:
A transfer sheet on which toner images free of broadening of edge portions and having sharp contours can be transferred even in the electrophotography or electrostatic printing of the transfer type using conductive or semiconductive toners, i.e., magnetic toners, is disclosed. This transfer sheet is characterized in that a conductive or semiconductive toner-receiving face having a volume specific resistance of at least 3.times.10.sup.13 .OMEGA.-cm is formed on at least one surface of a substrate of the transfer sheet.
摘要:
An electrophotographic process comprising forming an electrostatic image on the surface of a sensitive member, transferring the electrostatic image onto the surface of a transfer member, and developing the image so transferred. The process specifically involves using an overcoated sensitive member consisting essentially of an electrically conductive base, a photoconductive layer and a light-transmitting surface insulating layer, subjecting the sensitive member to a primary charging in a specific polarity using a direct current corona discharge, exposing light and dark images on the surface of the sensitive member and simultaneously subjecting it to a secondary charging until the surface of the sensitive member has the same polarity as in the primary charging and its potential becomes substantially equal to the untransferable upper limit potential, exposing the entire surface of the sensitive member to render the potential of the dark image area higher than the untransferable upper limit potential without substantially changing the potential of the light image area, transferring the electrostatic image so formed on the surface of the sensitive member to the surface of a transfer member, and then developing the electrostatic image so transferred thereby to form visible images.