Magnetic Recording Medium Surface Composition for Head Durability

The patent changes the physical and chemical parameters of the magnetic layer surface by controlling the particle size distribution of ferromagnetic powder (bimodal distribution with 0.5-2.0 μm and 2.0-5.0 μm particles), the content of binding agents (polyester resin 5-20 parts by mass, polyamide resin 5-20 parts by mass), and the addition of wax (5-20 parts by mass). These parameter changes modify the surface properties to reduce friction and prevent head element chipping during GTT, achieving head durability without increasing protective layer thickness

The patent uses a composite magnetic layer structure combining ferromagnetic powder particles of different sizes (bimodal distribution), multiple binding agents (polyester and polyamide resins), and wax. This composite formulation creates a surface with optimized mechanical properties that resist wear and prevent head element chipping while maintaining electromagnetic conversion characteristics

The patent performs preliminary action by pre-optimizing the magnetic layer surface properties before actual use. The specific formulation with bimodal ferromagnetic powder distribution, controlled binding agent content, and wax addition creates a surface that is pre-conditioned to prevent head element chipping from the outset, eliminating the need for surface wear to occur during durability testing

The patent changes the surface parameters of the magnetic layer by controlling particle size distribution (bimodal with 0.5-2.0 μm and 2.0-5.0 μm), binding agent content (polyester resin 5-20 parts by mass, polyamide resin 5-20 parts by mass), and adding wax (5-20 parts by mass). These parameter changes create a surface that maintains its properties during repeated sliding, preventing both head element chipping and electromagnetic conversion characteristic deterioration