| 摘要 |
PROBLEM TO BE SOLVED: To improve the dispersion characteristic of magnetic pigment by allowing one or more kinds of aralkyl phosphoric acid to be adsorbed on the surface of non- magnetic supporting material having a dispersion film in a polymer binder of magnetic pigment suitable for the use of the magnetic recording medium, etc. SOLUTION: A magnetic recording medium contains magnetic pigment which adsorbs on its surface one or more kinds of aralkyl phosphoric acids represented by a specific chemical formula (where Ar denotes aryl group and R denotes aliphatic group with 1-6 carbon atoms and (n) is an integer not smaller than one). The magnetic pigment is mixed with the compound represented by the formula with a solvent enough to generate a smooth magnetic paste, it is diluted with a polymer binder and solvent to be formed into solid content in percentage to be capable of further processing, (e.g. sand mill) the dispersion is processed to be applied on the substrate. The aralkyl phosphoric acid modifier gives a further imposed characteristic than in the case of phenyl phosphoric agent as the modifier, distributed material by the sand mill, etc., and a process for forming a film made of the obtained distributed material on a base material of the magnetic recording medium. The surface reforming compound of aralkyl phosphoric acid gives an improved characteristic to the magnetic pigment particle in comparison with a conventional one using phenyl phosphoric acid. |
