Magnetic Tape Surface Roughness and Abrasive Control

The patent applies parameter changes by precisely controlling the surface roughness parameter (Ra ≤ 1.8 nm) and introducing new parameters (logarithmic decrement ≤ 0.050, tilt angle cos θ between 0.85-1.00) to characterize the magnetic layer properties. These parameter adjustments resolve the contradiction by finding the optimal balance point where surface smoothness improves electromagnetic conversion while preventing component attachment that would degrade reproducing output during repeated running.

The patent employs composite materials by combining ferromagnetic hexagonal ferrite powder with specific binding agents and abrasives in a controlled ratio. This composite structure creates a magnetic layer that simultaneously achieves high surface smoothness for electromagnetic conversion and incorporates abrasive particles for effective abrasion properties, preventing the surface from becoming too smooth and causing component attachment during repeated running.

The patent applies the taking out principle by extracting and incorporating abrasive particles into the magnetic layer composition. These abrasive particles are specifically selected to remove components that attach to the head during running, separating the harmful attachment function from the beneficial surface smoothness function. The abrasive particles act as a cleaning mechanism that prevents component accumulation on the head surface.

The patent applies local quality by creating different functional zones within the magnetic layer. The binding agent provides surface smoothness in the upper region for electromagnetic conversion, while the abrasive particles are distributed to provide localized abrasion capability. This spatial differentiation of properties allows the surface to be smooth for conversion while maintaining abrasion properties to prevent component attachment.