MAGNETIC BRUSH CLEANING METHOD

PURPOSE:To form a strong magnetic brush, to increase a frictional force to a toner image carrier surface, and to improve cleaning performance by using a mixture of magnetic particles having large mean grain size and particles having small mean grain size as a cleaning carrier. CONSTITUTION:Particles 2 of magnetic material having large grain size sticks to the surface of a magnetic brush carrier by the magnetic force of a magnet 4 arranged on its reverse side as tufts cores of a brush to form the external form of the magnetic brush, and magnetic material particles 3 having small grain size stick round surfaces of the magnetic material particles 2 to form the magnetic brush for carrying toner. To manufacture carriers, iron powder is formed by pulverizing and an oxidized film and an insulating resin film are provided on its surface, if needed. The power is classified by sieves having different openings to magnetic powder having different mean grain sizes to mix together. In this case, small mean grain size of the magnetic powders at a peak position is