PURPOSE: To obtain the coating material having excellent coating workability and magnetic powder dispersibility without hindering the curing reaction by polyisocyanate by incorporating a resin having an ionic polar group in the molecule and having a specified moisture content as a binder component into this coating material.

CONSTITUTION: The resin contg. the ionic polar group, such as sulfonic acid base, at about 0.03 to 1equiv./kg in the molecule is used as the binder component. This resin includes a polyurethane resin, polyester resin, etc. Moisture is incorporated at about 0.05 to 20% of the weight of such binder resin into the binder resin soln. to adjust the yield stress value of the coating material viscosity to 200dyne/cm2. The magnetic coating compd. having the low viscosity and the excellent coating workability is obtd. without hindering the curing reaction by the polyisocyanate according to this constitution. Since the yield stress value of the magnetic coating compd. can be lowered, the magnetic field orientability at the time of coating is improved and a contribution is made to the improvement in the electromagnetic conversion characteristics of a magnetic tape.