| 摘要 |
<p>PURPOSE:To provide a magnetic particle which is superior in the strength and electrification property and enables to provide an excellent image, when it is used for a developer, by manufacturing the magnetic particle by a suspension polymerization process from a composition containing a polymerizable monomer, an amino resin and magnetic powder. CONSTITUTION:The magnetic particle is manufactured from a composition containing the polymerized monomer, the amino resin and the magnetic powder by a suspension polymerization process, and the magnetic powder is dispersed into the resin particles. Here the content of the amino resin is preferably 0.05-5 pts.wt. for 100 pts.wt. polymerizable monomer and the content of the magnetic powder is preferably 50-300 pts.wt. for the total 100 pts.wt. of the polymerizable monomer and the amino resin. Since the magnetic particle is obtained by a suspension polymerization of the composition containing the polymerizable monomer and besides the amino resin, the electrification property is excellent and further, the amino resin is present more on the surface side than the central part of the magnetic particle, so the electrification property is imparted efficiently. Thus the exfoliation does not generate and the strength is sufficient.</p> |
