Developing roller, process for producing developing roller, process cartridge and image forming apparatus
US7580660B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 2008 |
| Grant date | Aug 25, 2009 |
| Priority date | — |
| Expiry date | Oct 9, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/0863
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A developing roller has a conductive shaft member, a conductive elastic layer formed around the shaft member in a thickness of 0.5 mm to 6.0 mm, and a surface layer. The elastic layer contains carbon black and silicone rubber. The carbon black is in a content of 7% to 17% by mass and has at least two peaks in its particle size number distribution. The minimum diameter peak center in the particle size number distribution is within the range of 10 nm to 40 nm. The elastic layer has density within the range of 1.01 g/cm3 to 1.07 g/cm3. Where the ratios of carbon atoms to silicon atoms (C/Si), in the vicinity of the surface of the elastic layer, at depths of 100 μm and 200 μm from the surface of the elastic layer are represented by X, Y and Z, respectively, the X, Y and Z satisfy a specific relationship.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.