| 摘要 |
<p>PURPOSE:To improve the adhesion property between an aromatic polyamide support material and a magnetic layer, eliminate drop-out, make a magnetic recording material superior in running property and enhance the recording density per volume by using alcohol soluble polyamide resin for undercoating. CONSTITUTION:Desirably, aromatic polyamide of molecular weight 30,000 to 50,000 is formed by melting or solution to obtain a support material of thickness 3 to 10mum and maximum surface roughness (JISB0601) below 0.1mum. On this support material, alcohol of alcohol soluble polyamide resin such as a 6/66/610 nylon ternary copolymer obtained by mixing and copolymerizing materials of three or more kinds of homonylon and the solution of a chlorine-system solvent are applied and dried to form an undercoating layer of thickness 0.05 to 0.2mum desirably. A magnetic layer where ferromagnetic powder is dispersed in a binder is provided on this undercoating layer.</p> |
