| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide polymer-coated ferromagnetic particles by solving such a problem that it is difficult to obtain the polymer-coated ferromagnetic particles coated with a polymer while being dispersed in the state close to mono-dispersion because fine particles having ferromagnetism are easily aggregated. <P>SOLUTION: In the manufacturing method for the polymer-coated ferromagnetic particles, uniform and stable polymer coating is performed according to following processes: a process of allowing hydrophilic ferromagnetic particles to adsorb a hydrophobilizing material, and thereby hydrophobilizing the hydrophilic ferromagnetic particles; a process of hydrophilizing the hydrophobilized ferromagnetic particles while suppressing the ionic strength by using a surface active agent having nonionic hydrophilic groups, thereby obtaining dispersion liquid; a process of emulsifying a monomer solution by using a nonionic surface active agent and an ionic surface active agent to obtain an emulsion, mixing the emulsion and the dispersion liquid, and thereby obtaining emulsion liquid; and a process of emulsion-polymerizing the emulsion liquid. As a result, the polymer-coated ferromagnetic particles having excellent response to a magnetic field can be obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
