| 摘要 |
<p>PURPOSE:To effectively manufacture coating carrier for electrostatic charge development with uniform particle size by mixing and kneading together a resin and a magnetic powder, extruding the resultant from a nozzle having a very small bore, and cutting into lengths equal to the nozzle bore to generate a granular form. CONSTITUTION:In a manufacturing method for a carrier where a magnetic powder such as oxide chiefly containing iron is coated with a resin, 40-90wt.% of magnetic powder and 60-10wt.% of resin as binder are mixed and kneaded together, then the resultant is extruded into a thin wire from a nozzle having a bore of 30 to 150mum and the wire is cut into lengths approx. equal to the bore, and the produced particles are processed as to have a spherical form. The same size of the nozzle bore and cut lengths ensures effective manufacturing of particles having uniform particle size. The particles can further be turned to spherical form by the surface tension through softening of the resin of shell surrounding the magnetic particles by setting the particles in a hot air stream which is set higher than the glass transfer point of the resin.</p> |
