| abstract |
PURPOSE:To improve dispersion of a magnetic body in a toner prepd. by polymerizing a compsn. contg. a polymerizable monomer and a magnetic body by incorporating a specified amt. of Si element which has been subjected to silane coupling treatment into the compsn. CONSTITUTION:A toner is formed by carrying out suspension polymn. of a compsn. contg. a polymerizable monomer (e.g. styrene monomer, etc.) and a magnetic body. 0.05-1.5wt.% (basing on the amt. of Fe element contained in FeSO4, etc. as the magnetic body) Si element is incorporated in the toner, wherein said Si element is subjected to silane coupling treatment on the surface. Suitable compds. contg. the Si element are such as silicates, silica sol formed by the hydrolysis of silicates, and suitable silane coupling agents are gamma- methacryloxypropyl trimethoxy silane, gamma-mercaptopropyl trimethoxy silane, etc. By this method, a magnetic material can be dispersed uniformly in a polymerizable monomer, and electrification characteristic of a magnetic toner due to frictional electricity is improved. |