PURPOSE: To realize high dispersibility of magnetic powder without using a dispersing agent and to obtain a magnetic recording medium with high recording density by using such a magnetic powder coated with alternate copolymer of polyoxyethylene allylmethyldiether and maleic anhydride.
CONSTITUTION: The water-base coating material containing magnetic powder consists of acrylic resin and water as the main components and contains the magnetic powder dispersed therein, the particles of which are coated with alternate copolymer of polyoxyethylene allylmethyldiether and maleic anhydride. The water-base coating material is applied on the surface of a substrate and dried to give a coating-type magnetic layer. Thereby, the magnetic powder is highly dispersed in the water-base coating material without addition of a dispersing agent, and the magnetic recording medium having high performance and excellent recording density can be obtained.
TAMAURA YUTAKA
TAKAHASHI KATSUNOBU
