| 摘要 |
PURPOSE:To obtain a perfectly spherical toner by dispersing an agent for giving toner characteristics and an oil-soluble polymn. initiator into a monomer for producing a thermoplastic resin to suspension-polymerize it, and further polymerizing it in a suspension phase lower in surface activity after removing an aq. dispersion medium phase contg. an excess of a suspending agent. CONSTITUTION:A mixture of a polymerizable monomer for producing a thermoplastic resin dispersing or dissolving a toner characteristics giving agent and an oil-soluble polymn. initiator is polymerized in an aq. soln. of a suspension stabilizer of comparatively high concn. with high-speed agitation. The produced polymer is once separated and the dispersion medium is removed. Then, fresh water or a fresh aq. soln. of suspension stabilizer comparatively low in surface activity is added to polymerize the remaining monomer again. Concurrence of emulsion polymn. can be suppressed by doing so, and the obtained toner particles are smooth on the surfaces, perfectly spherical, and almost free from microfine particles attached to the toner spheres. Such toner particles have excellent fluidity and chargeability and other electric characteristics. |
