Charging device including movable charging brush contactable to member to be charged, and image forming apparatus using same

A process cartridge detachably mountable to an image forming apparatus, comprising:

• a movable member to be charged having a surface charge injection layer with a volume resistivity of 1.times.10.sup.10 -1.times.10.sup.14 .OMEGA.cm, said surface layer being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member including a movable charging brush comprising fibers contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>4,
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said charging brush, and N (mm) is a contact width between said member to be charged and said charging brush, measured in a movement direction of said member to be charged.

An image forming apparatus comprising:

• a movable member to be charged having a surface charge injection layer with a volume resistivity of 1.times.10.sup.10 -1.times.10.sup.14 .OMEGA.cm, said surface layer being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member inducing a movable charging brush comprising fibers contactable with said member to be charged and supplied with a voltage;
• and
• image forming means for forming an image on said surface layer;
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>4,
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said charging brush, and N (mm) is a contact width between said member to be charged and said charging brush, measured in a movement direction of said member to be charged.

A charging device comprising:

• a movable member to be charged having a surface charge injection layer with a volume resistivity of 1.times.10.sup.10 -1.times.10.sup.14 .OMEGA.cm;
• a charging member for charging said member to be charged, said charging member including a movable conductive particle layer contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>0.2
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said conductive particle layer, and N (mm) is a contact width between said member to be charged and said conductive particle layer, measured in a movement direction of said member to be charged.

A process cartridge detachably mountable to an image forming apparatus comprising:

• a movable member to be charged having a surface charge injection layer with a volume resistivity of 1.times.10.sup.10 -1.times.10.sup.14 .OMEGA.cm, said surface layer being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member including a movable conductive particle layer contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>0.2
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said conductive particle layer, and N (mm) is a contact width between said member to be charged and said conductive particle layer, measured in a movement direction of said member to be charged.

An image forming apparatus comprising:

• a movable member to be charged having a surface charge injection layer with a volume resistivity of 1.times.10.sup.10 -1.times.10.sup.14 .OMEGA.cm, said surface layer being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member including a movable conductive particle layer contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>0.2
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said conductive particle layer, and N (mm) is a contact width between said member to be charged and said conductive particle layer, measured in a movement direction of said member to be charged.

A charging device comprising:

• a movable member to be charged;
• a charging member for charging said member to be charged, said charging member including a movable charging brush comprising fibers contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>4,
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said charging brush, and N (mm) is a contact width between said member to be charged and said charging brush, measured in a movement direction of said member to be charged.

A process cartridge detachably mountable to an image forming apparatus, comprising:

• a movable member to be charged, said member to be charged being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member including a movable charging brush comprising fibers contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>4,
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said charging brush, and N (mm) is a contact width between said member to be charged and said charging brush, measured in a movement direction of said member to be charged.

A charging device comprising:

• a movable member to be charged;
• a charging member for charging said member to be charged, said charging member including a movable conductive particle layer contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>0.2
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said conductive particle layer, and N (mm) is a contact width between said member to be charged and said conductive particle layer, measured in a movement direction of said member to be charged.

A process cartridge detachably mountable to an image forming apparatus comprising:

• a movable member to be charged, said member to be charged being capable of bearing an image;
• a charging member for charging said member to be charged, said charging member including a movable conductive particle layer contactable with said member to be charged and supplied with a voltage;
• and
• wherein said movable member is driven such that the following relationship is satisfied:
• N(Vk-Vb)/Vk>0.2
• where Vk (mm/sec) is a movement speed of the surface of said member to be charged, Vb (mm/sec) is a movement speed of an outer peripheral surface of said conductive particle layer, and N (m/n) is a contact width between said member to be charged and said conductive particle layer, measured in a movement direction of said member to be charged.