| 摘要 |
PURPOSE:To easily prevent the oxidation of esp. ferromagnetic metal powder coated with an inorganic macromolecular film, by immersing the metal powder coated with the inorganic macromolecular film in inactive liquid substance held at a temp. lower than that of the metal powder in the atmosphere of inert gas. CONSTITUTION:Metal powder (esp. ferromagnetic iron powder composed of Fe only or the like) coated with an inorganic macromolecular film based on oxides of Si and/or Al is treated by immersing it in liquid substance inactive to said metal powder. As said liquid substance, one or more of substances, e.g. hydrocarbon solvents such as toluene, having a stable property to the property and oxidation of the metal powder and being liquid at an ordinary temp. may be used. By charging and immersing the metal powder coated with the inorganic macromolecular film held at a high temp. in said liquid substance hold at a temp. lower than said high temp. in the atmosphere of inert gas, the oxidation of the metal powder is prevented. |
