Development device and image forming apparatus
View Patent ↗A development device includes a developer carrier configured to supply developer on a latent image formed on a latent image carrier to visualize the latent image. Wherein the developer carrier includes: an elastic layer formed on an outer circumferential surface of a conductive support body, the elastic layer including urethane rubber; and a top layer formed by treating a surface of the elastic layer with treatment solution that includes urethane polymer, silicone-based additive and conductive agent. The top layer includes convex parts that include the urethane rubber and concave parts in which the silicone-based additive and the conductive agent are laminated.
1. A development device, comprising:
a developer carrier configured to supply developer on a latent image formed on a latent image carrier to visualize the latent image, wherein
the developer carrier includes:
an elastic layer formed on an outer circumferential surface of a conductive support body, the elastic layer including urethane rubber; and
a top layer formed by treating a surface of the elastic layer with treatment solution that includes urethane polymer, silicone-based additive and conductive agent;
the top layer includes:
convex parts that include the urethane rubber; and
concave parts in which the silicone-based additive and the conductive agent are laminated.
2. The development device according to claim 1 , wherein
the conductive agent is positioned under the silicone-based additive in the concave parts.
3. The development device according to claim 2 , wherein
the convex parts are formed of urethane component.
4. The development device according to claim 1 , wherein
the silicone-based additive is silicone-based particles.
5. The development device according to claim 4 , wherein
surfaces of the concave parts are formed in a sea-island structure in which the conductive agent forms a sea part and the silicone-based particles forms island parts.
6. The development device according to claim 1 , wherein
the conductive agent is carbon black.
7. The development device according to claim 1 , wherein
ASKER C hardness of the top layer ranges from 77° to 80°.
8. The development device according to claim 1 , wherein
the developer is negatively charged.
9. The development device according to claim 1 , wherein
the top layer includes a penetration layer in which the urethane prepolymer has penetrated in the urethane rubber.
10. An image forming apparatus, comprising the development device according to claim 1 .
11. The development device according to claim 1 , wherein
a surface of the elastic layer has a surface roughness of 5-10 μm which is measured with a ten-point average surface roughness measurement method.
12. The development device according to claim 11 , wherein
the ten-point average surface roughness measurement method is based on JIS B0601-1994.
13. The development device according to claim 1 , wherein
the conductive agent is carbon black of which a primary particle diameter ranges from 15 nm-40 nm, and
the silicone-based additive is silicone-based particles of which a primary particle diameter ranges from 0.5 μm-2.0 μm.