Patent ID: 7252920

Claim:
A method for manufacturing a polymerized toner comprising a process for forming fine droplets of a polymerizable monomer composition containing a polymerizable monomer and a colorant, in an aqueous dispersion medium, and a process for polymerizing the polymerizable monomer composition after the process for forming fine droplets; wherein, the process for forming fine droplets comprising the steps of: step (1) preparing an agitating apparatus having an agitator equipped with an agitating blade or rotor and a dispersion supply tank, said dispersion supply tank being connected with the agitator through a line; step (2) providing a polymerizable monomer composition and an aqueous dispersion medium into the dispersion supply tank; and; step (3) mixing the polymerizable monomer composition and the aqueous dispersion medium by the agitator under controlled agitation to obtain a dispersion of fine droplets; step (4) feeding back the dispersion from the outlet port of the agitator through a line into the dispersion supply tank and circulating the dispersion; the agitation being controlled by the following parameters: R/θ≧2, and R≧30 m/s or more, wherein the peripheral velocity (m/s) of the agitating blade or rotor of the agitator is designated by R, and the number of circulations is designated by θ; θ being represented by (throughput of the dispersion (liter/h)×agitating time (h))/(provided quantity in step (2) of the polymerizable monomer composition and the aqueous dispersion medium (liter)); the throughput being the amount of dispersion that is fed back into the dispersion supply tank in step (4); θ being ≧1; and the internal pressure of the agitator is controlled within a range between 0.01 and 15 MPa; and step (5) providing the resulting dispersion to the process for polymerizing.