Process for reversal development using inductively chargeable magnetic powdery developer

A reversal developing process for developing an electrostatic latent image on a surface, the latent image being in the form of first charged areas and second lesser charged areas in which the potential of the first charged areas is substantially more in absolute value than that of the second charged areas, the potential of the first charged areas being of a given polarity, the process comprising:

• forming a first toner brush with inductively chargeable ferromagnetic toner on a first shell by a magnetostatic attraction force caused by a permanent magnet member incorporated within the shell;
• subjecting the first toner brush to the electrostatic force of the charged areas for adhering the toner as a layer on the first charged areas of the surface;
• charging with a D.C. charger the toner layer adhering to the first areas and recharging the second areas both with a uniform amount of charge of the same polarity as the potential of the first areas;
• damping the electrostatic charge on the first charged areas by dark decay and neutralization by the toner layer;
• forming a second toner brush with inductively chargeable ferromagnetic toner on a second shell by a magnetostatic attraction force caused by a permanent magnet member incorporated within the shell;
• and
• interpositioning the second toner brush and the surface for subjecting the second toner brush to the electrostatic force of the toner layer on the first charged areas and the electrostatic force of the second charged areas for magnetically removing the previously adhered toner and adhering toner on the second recharged areas in a single pass of the second toner brush.