Cleaning device for image bearing member, process cartridge and image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorsTakayuki Kanazawa, Shuhei Tokiwa
Life of this patent
Estimating the term…
Abstract
A cleaning device has: a cleaning frame; a cleaning member which, after transfer through contact with an image bearing member, removes a developer remaining on the image bearing member; and a sheet member having flexibility and coming into contact with the image bearing member at an upstream side of a contact position between the cleaning member and the image bearing member in the rotation direction of the image bearing member. An external additive is an inorganic salt having a charging polarity on the positive side with respect to the developer, and work functions Φ(S), Φ(A), Φ(T) of the sheet member, the external additive and the developer satisfy 0≤|Φ(A)−Φ(S)|<0.57; and Φ(A)<Φ(T).
Claims10
A cleaning device, comprising:
- a cleaning frame;
- a cleaning member having one end attached to the cleaning frame and the other end that is a free end, the cleaning member coming into contact with an image bearing member so as to remove developer remaining on the image bearing member after transfer of a developer image from the image bearing member, the image bearing member being capable of rotating and bearing a developer image which is formed of a developer containing an external additive;
- and
- a sheet member having flexibility, and having one end attached to the cleaning frame and the other end that comes into contact with the image bearing member at an upstream side of a contact position between the cleaning member and the image bearing member in the rotation direction of the image bearing member,
- wherein the external additive is an inorganic salt having a charging polarity on the positive side with respect to the developer;
- and
- wherein a work function Φ(S) of the sheet member, a work function Φ(A) of the external additive and a work function Φ(T) of the developer satisfy Expressions (1) and (2):
- 0 (eV)≤|Φ(A)−Φ(S)|<0.57 (eV) (1)
- Φ(A)<Φ(T) (2).
A process cartridge, comprising:
- an image bearing member capable of rotating and bearing a developer image which is formed of a developer containing an external additive;
- a cleaning frame;
- a cleaning member having one end attached to the cleaning frame and the other end that is a free end, the cleaning member coming into contact with the image bearing member so as to remove the developer remaining on the image bearing member after transfer of the developer image from the image bearing member;
- and
- a sheet member having flexibility, and having one end attached to the cleaning frame and the other end that comes into contact with the image bearing member at an upstream side of a contact position between the cleaning member and the image bearing member in the rotation direction of the image bearing member,
- wherein the external additive is an inorganic salt having a charging polarity on the positive side with respect to the developer;
- and
- wherein a work function Φ(S) of the sheet member, a work function Φ(A) of the external additive and a work function Φ(T) of the developer satisfy Expressions (3) and (4):
- 0 (eV)≤|Φ(A)−Φ(S)|<0.57 (eV) (3)
- Φ(A)<Φ(T) (4).
An image forming apparatus, comprising:
- an image bearing member capable of rotating and bearing a developer image which is formed of a developer containing an external additive;
- a transfer member that transfers the developer image borne on the image bearing member to a transferring material;
- a cleaning frame;
- a cleaning member having one end attached to the cleaning frame and the other end that is a free end, the cleaning member coming into contact with the image bearing member so as to remove the developer remaining on the image bearing member after transfer of the developer image from the image bearing member;
- and
- a sheet member having flexibility, and having one end attached to the cleaning frame and the other end that comes into contact with the image bearing member at an upstream side of a contact position between the cleaning member and the image bearing member in the rotation direction of the image bearing member,
- wherein the external additive is an inorganic salt having a charging polarity on the positive side with respect to the developer;
- and wherein a work function Φ(S) of the sheet member, a work function Φ(A) of the external additive and a work function Φ(T) of the developer satisfy Expressions (5) and (6):
- 0 (eV)≥|Φ(A)−Φ(S)|<0.57 (eV) (5)
- Φ(A)<Φ(T) (6).
Dependencies are inferred from the claim text.