摘要:
A magnetic recording medium comprising a nonmagnetic substrate, a liquid lubricant-containing coating layer having a porosity (U) formed on the substrate, and a magnetic layer having a porosity (M) formed directly on the coating layer. The ratio of porosity (U/M) between the coating and magnetic layers is between 0.75 and 1.25. The volume percentage of the lubricant contained in the pores of the coating layer based on the whole pore volume in the coating layer is from 35 to 85%. This improves the durability of the magnetic layer.
摘要:
A magnetic recording medium comprising a nonmagnetic substrate, a liquid lubricant-containing coating layer having a porosity (U) formed on the substrate, and a magnetic layer having a porosity (M) formed directly on the coating layer. The ratio of porosity (U/M) between the coating and magnetic layers is between 0.75 and 1.25. The volume percentage of the lubricant contained in the pores of the coating layer based on the whole pore volume in the coating layer is from 35 to 85%. This improves the durability of the magnetic layer.
摘要:
A high recording density magnetic recording medium including a non-magnetic base film, a magnetic layer, and an undercoat layer provided therebetween. The undercoat layer includes non-magnetic particles, a binder resin, and a lubricant. The non-magnetic particles comprise (1) a non-magnetic iron oxide with an acicular ratio ranging from 5 to 10 and a long axis length ranging from 0.05 to 0.3 .mu.m, and (2) a carbon black having a structure constitution, and the weight ratio between said non-magnetic iron oxide and said carbon black is within the range between 85/15 and 99/1.