Perpendicular Magnetic Field Orientation of Acicular Particles. Oblique orientation with field gradient and viscosity gradient in coating.

In order to prepare obliquely oriented tapes having a definite orientation angle, the LIPS (longitudinally oriented inside layer and perpendicularly oriented at surface layer) orienting method was improved. The permanent magnets pairs of the LIPS for perpendicular orientation were replaced by an electromagnet with long iron plates for extension of magnetic poles. Obliquely oriented tapes are easily prepared by choosing the coating speed and the drying condition. Coating sdried in the perpendicular field with intensity gradient are found not to be oriented perpendicularly but obliquely. It is considered that inner-layer particles are more easily displaced by the field gradient force than surface particles because of the effect of the viscosity gradient in the coating drying process.