| 摘要 |
<p>PURPOSE:To obtain a recording medium of a magnetic floppy disc having high coercive force and having excellent flatness and practicality, by providing the 2nd magnetic recording layer thicker in film thickness than the 1st magnetic recording medium on the other surface of the 1st magnetic recording layer formed on the one surface of a flexible polymer substrate. CONSTITUTION:The 1st magnetic recording layer 2 is formed by sputtering on the one surface of a film substrate consisting of a flexible polymer material of polyimide, polyester, etc., and in succession, the 2nd magnetic recording layer 3 is formed by sputtering on the other surface of the substrate 1. The layers 2, 3 are formed by sputtering Co-Cr thin films on the film substrate 1, and the 1st layer 2 is formed to 0.5-1.0mum thickness and the 2nd layer 3 is formed thicker by 2-10% as compared to the layer 2. If the sputtering for the layers 2, 3 is controlled in such a way that the substrate 1 is kept at the highest possible temp. within the range where the substrate is kept free from thermal damage, the magnetic recording meidum having high coercive force Hc is obtd.</p> |
