MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To obtain a magnetic recording medium which is stable to oxidation particularly in a high temp. and high moisture atmosphere and has excellent still durability and wear resistance by forming a magnetic layer contg. magnetic powder of a metal of which the pH at the isoelectric point is of a specific value or above on a base. CONSTITUTION:0.1g Magnetic powder of a metal such as an Fe-Al alloy, Fe-Ni- Co alloy, Co-Ni alloy or the like is added and dispersed to and in a soln. prepd. by adding HCl or NaCl to 100ml water and adjusting the pH to a suitable value, then the pH at which the xsi-potential is zero (isolelectric point) is measured. A magnetic coating prepd. by dispersing the soln. having >=7.5pH in a binder soln. is coated on a base and is dried and cured to form a magnetic layer. A magnetic recording medium which has a large squareness ratio, is low in saturation magnetization even in a high temp. and high humidity atmosphere and has a large S/N and long still durability is thus obtd.