摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide coated magnetite particles being good in a rise in electrostatic charge and not generating an excessive electrostatic charge. <P>SOLUTION: The surface of a magnetite core particle is coated with a silane compound. The content of a divalent iron present on the surface of the core particle is 20-30% based on the entire amount of the iron present on the surface of the core particle. Further, the alkyl groups contained in the silane compound each has 2-10 carbon atoms. It is desirable that the crystallite diameter of the magnetite as measured by an X-ray diffraction method is 60-90 nm. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |