| 摘要 |
<p>PURPOSE:To increase the lubricating effect even at a low temperature and decrease greatly the exfoliation of the magnetic powder, by adding the ethylene oxide condensed to the sorbitan high-class fatty acid ester type surface active agent to the magnetic coating meterial and then coating it onto the supporter. CONSTITUTION:The sorbitan high-class fatty acid ester type surface active agent condensed with the ethylene oxide (Kao Atreus made ''Tween80 '' or the like) is added to the mixture of the magnetic powder, the binder resin and the solvent each. The magnetic coating material thus obtained is coated onto the substrate of polyester or the like, and thus the magnetic tape is produced after the drying process. Thus the satisfactory lubricating function is secured even at -20 deg.C or so in the winter season, and no magnetic powder is exfoliated to stick to the magnetic head. As a result, a highly reliable magnetic recording medium is obtained.</p> |
