Image bearing member-protecting agent, protecting agent supplying device, process cartridge, image forming apparatus and image forming method

• US 20110052286A1
• Filed: 08/24/2010
• Published: 03/03/2011
• Est. Priority Date: 09/02/2009
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Hasegawa, Kunio, Urayama, Taichi, Tanaka, Shinya, Nakai, Hiroshi
• Granted Patent: US 8,351,838 B2
• Time in Patent Office: Days
• US Class Current: 399/346
• CPC Class Codes: G03G 21/0017 Details relating to the internal structure or chemical composition of the blades
• CPC Class Codes: G03G 21/0029 Details relating to the blade support
• CPC Class Codes: G03G 21/1671 for the photosensitive element
• CPC Class Codes: G03G 5/14704 comprising inorganic material
• CPC Class Codes: G03G 5/14734 Polymers comprising at least one carboxyl radical, e.g. polyacrylic acid, polycrotonic acid, polymaleic acid; Derivatives thereof, e.g. their esters, salts, anhydrides, nitriles, amides
• CPC Class Codes: G03G 5/14795 Macromolecular compounds characterised by their physical properties

Abstract

An image bearing member-protecting agent which is supplied to an image bearing member for protecting the image bearing member, the image bearing member-protecting agent including a fatty acid metal salt and an inorganic lubricant, wherein the image bearing member-protecting agent is formed by compression molding of powder containing at least the fatty acid metal salt and the inorganic lubricant, and wherein the image bearing member-protecting agent satisfies the relation 1.0<A/B, where A denotes a density at end portions in the longitudinal direction of the image bearing member-protecting agent and B denotes a density at a central portion in the longitudinal direction of the image bearing member-protecting agent.

Claims

1. An image bearing member-protecting agent which is supplied to an image bearing member for protecting the image bearing member, the image bearing member-protecting agent comprising:

a fatty acid metal salt, and

an inorganic lubricant,

wherein the image bearing member-protecting agent is formed by compression molding of powder containing at least the fatty acid metal salt and the inorganic lubricant, and

wherein the image bearing member-protecting agent satisfies the relation 1.0<

A/B, where A denotes a density at end portions in the longitudinal direction of the image bearing member-protecting agent and B denotes a density at a central portion in the longitudinal direction of the image bearing member-protecting agent.

2. The image bearing member-protecting agent according to claim 1, wherein the image bearing member-protecting agent satisfies the relation 1.0<

A/B≦

1.45.

3. The image bearing member-protecting agent according to claim 1, wherein the fatty acid metal salt is zinc stearate.

4. The image bearing member-protecting agent according to claim 1, wherein the inorganic lubricant is boron nitride.

5. A protecting agent-supplying device comprising:

an image bearing member-protecting agent which is supplied to an image bearing member for protecting the image bearing member,

wherein the image bearing member-protecting agent comprises a fatty acid metal salt and an inorganic lubricant,

wherein the image bearing member-protecting agent is formed by compression molding of powder containing at least the fatty acid metal salt and the inorganic lubricant, and

wherein the image bearing member-protecting agent satisfies the relation 1.0<

A/B, where A denotes a density at end portions in the longitudinal direction of the image bearing member-protecting agent and B denotes a density at a central portion in the longitudinal direction of the image bearing member-protecting agent.

6. The protecting agent-supplying device according to claim 5, further comprising a supplying member which scrapes off the image bearing member-protecting agent and supplies the image bearing member-protecting agent to an image bearing member.

7. The protecting agent-supplying device according to claim 5, further comprising a layer-forming member which forms a layer, on the image bearing member, of the image bearing member-protecting agent supplied on the image bearing member.

8. An image forming apparatus comprising:

a protecting agent-supplying device, and

an image bearing member,

wherein the protecting agent-supplying device comprises an image bearing member-protecting agent which is supplied to the image bearing member for protecting the image bearing member,

wherein the image bearing member-protecting agent comprises a fatty acid metal salt and an inorganic lubricant,

wherein the image bearing member-protecting agent is formed by compression molding of powder containing at least the fatty acid metal salt and the inorganic lubricant, and

wherein the image bearing member-protecting agent satisfies the relation 1.0<

A/B, where A denotes a density at end portions in the longitudinal direction of the image bearing member-protecting agent and B denotes a density at a central portion in the longitudinal direction of the image bearing member-protecting agent.

9. The image forming apparatus according to claim 8, further comprising a cleaning device for removing from the image bearing member toner particles remaining on the image bearing member,

wherein the cleaning device is provided so as to be in contact with the image bearing member, and

wherein the cleaning device is located, in a direction in which the image bearing member is moved, downstream of a position where a toner image on the image bearing member is transferred onto a recording medium but upstream of a position where an image-bearing member protecting agent is supplied by the protecting agent-supplying device.

10. The image forming apparatus according to claim 8, wherein the image bearing member has a layer containing a thermosetting resin at least the uppermost surface thereof.

11. The image forming apparatus according to claim 8, further comprising a charging unit which is provided so as to face the image bearing member and configured to charge the image bearing member.

12. The image forming apparatus according to claim 11, wherein the charging unit comprises a voltage-applying unit configured to apply a voltage containing an alternating-current component.