| 摘要 |
PURPOSE:To prevent a magnetic powder from adhering to a microcapsule wall, of damaging the microcapsule wall by sufficiently stably arranging a surfactant to the peripheral surface of the magnetic powder. CONSTITUTION:A surfactant 33B is constituted of a fatty acid type surfactant and a liquid mixture of the surfactant 33B, a magnetic powder 33A and a hydrophobic solvent 34 is treated using a bead mill or a ball mill to arrange the surfactant 33B to the peripheral surface of the magnetic powder 33A. By this method, the surfactant can be arranged to the peripheral surface of the magnetic powder in a sufficiently stable manner and it can be prevented that the magnetic powder adheres to a microcapsule wall or damages said wall. |
