NON-MAGNETIC POWDER FOR MAGNETIC RECORDING MEDIUM, ITS MANUFACTURING METHOD AND MAGNETIC RECORDING MEDIUM USING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain non-magnetic powder having satisfactory dispersibility obtained when the non-magnetic powder is dispersed in a binder to prepare paint for a non-magnetic layer, in the non-magnetic powder used for the non-magnetic layer of a coating type magnetic recording medium having a layer structure. SOLUTION: The non-magnetic powder for the magnetic recording medium comprises particles consisting essentially of an iron compound, having the maximum value (the magnitude of pores concentrated to the most) of pore volumes in the range of 0.01 to 0.05μm pore radius of the 0.0018 to 0.1μm pore radius calculated by a mercury pressure method and showing≤30% sum of pore volume having 0.0018 to 0.01μm pore radius to the total sum value of the pore volume having 0.0018 to 0.1μm pore radius in the measured range. COPYRIGHT: (C)2006,JPO&NCIPI