Method of diminishing unreacted monomer in vinyl polymer and toner resin reduced in unreacted monomer content

摘要

The method of decreasing unreacted monomer in vinyl polymer of the present invention is a method comprising adding a water-soluble inorganic salt that is able to solubilize unreacted monomer contained in vinyl polymer to an aqueous dispersion in which particles of vinyl polymer are dispersed in an aqueous medium, followed by solubilizing the unreacted monomer and removing the unreacted monomer together with the aqueous medium. According to this method, the amount of unreacted monomer present in a polymer can be efficiently and reliably decreased at low cost without requiring a special apparatus or thermal energy, etc. In addition, the toner resin of the present invention has for its constituent component a vinyl polymer in which the amount of unreacted monomer has been decreased by the method described above. In addition to solving the problem of a foul odor being generated during toner production and fixation when copying, the vinyl polymer obtained according to the method of the present invention also has superior effects such as contributing to improvement of toner characteristics.