| 摘要 |
Particles of a nonmagnetic material are rendered magnetic by contacting their surfaces with a magnetizing reagent comprising water containing particles of a magnetic material, each of which has a two layer surfactant coating including an inner layer and an outer layer. The inner layer covers the magnetic particle and is a monomolecular layer of a first water soluble, organic, heteropolar surfactant containing at least 3 carbon atoms and having a functional group on one end which bonds with the magnetic particle. The outer layer coats the inner layer and is a monomolecular layer of a second water soluble, organic heteropolar surfactant containing at least three carbon atoms and having a hydrophobic end bonded to the hydrophobic end of the first surfactant and a functional group on the other end capable of bonding with the particles to be magnetized. |
