| 摘要 |
PURPOSE:To improve the dispersibility in the binder of the magnetic powder of cobalt containing iron oxide by blowing one of the gas like carbon dioxide gas, sulfur dioxide gas, and nitrogen dioxide gas into the water medium dispersed the magnetic powder until hydrogen ion density of water with medium is below pH 7. CONSTITUTION:Cobalt ferrite is grown in an epitaxial form to the iron oxide magnetic powder and then gained magnetic powder of cobalt containing iron oxide having a pH of about 9 after water cleaning, particle diameter of about 0.3mum, axis ratio of about 7 and cobalt inclusion of about 1% in weight, is dispersed into the water. Then, carbon dioxide gas is blown here to adjust the pH under 7 and the powder is filtrated, cleaned and dried. Next, the powder is attached on the polyester film to form a magnetic tape. By doing so, magnetic tape excellent in the edge, orientation ratio, freqrency characteristics, etc. can be obtained. |
