| 摘要 |
PURPOSE:To manufacture the magnetic fluid capable of reforming the magnetic powder surface thereby stably maintaining the dispersed state in fluorine oil whereinto the reformed magnetic powder is dispersed by using a specific fluorine compound as an interfacial activator. CONSTITUTION:The magnetic fluid is composed of a fluorine compound, magnetic powder and fluorine oil represented by a structural formula wherein Rf represents perfluoroalkyl radical in carbon number of 1-10 while n represents 1-3. At this time, a small quantity of fluorine compound having so high interfacial activating effect can efficiently reform the magnetic lowder surface. Besides, since the reformed magnetic powder can be dispersed into a fluorine oil, the title fluid can stably maintain the dispersed state of the magnetic powder. Furthermore, the fluorine oil can be used as a medium of the magnetic fluid so that excellent thermal resistance, cold resistance, chemical resistance of the magnetic fluid can be assured. |
