Noninvariant Hypersurfaces of Sasakian Space Forms

An image forming apparatus for an electrophotographic process utilizes an agglomerate of toner powder so as to avoid scattering of toner powder. When the agglomerate is crushed or de-agglomerated to fine toner powder, only toner powder having a proper particle size for electrophotography is selected by a mesh member through which the toner must pass. The process can be utilized for a single component toner developing system and a component toner developing system.