Magnetic recording elements, process for making the same and their use in recording

摘要

Magnetic recording elements having at least one magnetic recording layer containing acicular magnetic particles that have magnetocrystalline anisotropy, shape anisotropy which provides a preferred axis of magnetization and a coercivities of at least 450 Oersteds. These particles are dispersed in a binder and form a distribution that imparts an isotropic magnetic response to the magnetic recording layer. A Process for preparing the above magnetic recording elements is also disclosed. According to this process, the aforementioned magnetic particles are dispersed in a liquid medium. The dispersion is formed into a magnetic recording layer while establishing a distribution of particles that has spherically symmetrical magnetic properties (symmetry that is three-dimensional). The layer is then solidified while maintaining this distribution. A magnetic recording method is also disclosed. This method involves (1) providing a signal modulated magnetic field by means of a gapped magnetic ring head, (2) subjecting to that field a magnetic recording layer of the type previously described and (3) causing relative motion between the head and the layer.