A Particulate Medium Oriented Longitudinally Inside and Perpendicularly at Surface

This report takes another look at the VAST (Vertical magnetic orientation-AC demagnetization-Smoothing period-sequential Train) technique used to fabricate double-layer particulate media oriented longitudinally inside and perpendicularly at the surface from CrO2 particles and nitrocellulose with a urethane binder. Infrared irradiation was performed to evaporate the solvent instead of natural evaporation to improve the viscosity of the surface perpendicular oriented layer, and to ensure a controlled thin, uniform thickness surface layer.