| 摘要 |
PURPOSE:To provide a titled carrier which has the strength to the extent of obviating the generation of particle breakdown, improved fluidity and stabilized characteristic of the surface condition by consisting essntially of said carrier of magnet composed of a spherical material having 1.0-3.5g/cc apparent density, 10<6>-10<10>OMEGA.cm specific resistance and 30-500mum average grain size. CONSTITUTION:The reason for using the magnetite as essential component lies in that a magnetic brush is made softer and that the image is less roughened. Brittle structure is resulted from excessive bulkiness and the magnetic brush collapses gradually during use if the apparent density is <1.0g/cc. The density is too high and the good image characteristic is not obtainable conversely if the apparent density exceeds 3.5g/cc. The image density decreases and the image characteristic is poor if the specific resistance exceeds >=10<10>OMEGA.cm and the image characteristic is too hard in contrast at <10<5>OMEGA.cm. The carrier is too fine and suspends and is thus inadequate for being compounded with a toner for electrophtographic development if the average grain size is <30mum. The carrier is too rough and the image characteristic is poor if the average grain size excceds 500mum. |
