| 摘要 |
A developing roller (1000) for providing a magnetic brush for a printer or copier has a substantially cylindrical outer surface (1021) which comprises a regular or irregular array of a number of isolated areas (1100), each isolated area being provided by a recess in the outer surface. Each recess is completely surrounded on all sides and isolated from any neighbouring isolated area by separation zones (1900) being part of the substantially cylindrical outer surface. |
