Magnetic recording medium and magnetic tape cassette mounted with the magnetic recording medium

摘要

A magnetic recording medium and a magnetic tape cassette are disclosed, comprising a non-magnetic support having formed on one surface only thereof at least two layers including a lower layer and an upper magnetic layer formed thereon, wherein the surface electric resistance (Rs) of the surface of the magnetic layer of said magnetic recording medium is 109 OMEGA /sq or less, the non-magnetic support contains at least three different kinds of particles which vary from each other in at least one property of mean particle diameter and Mohs' hardness, and the opposite surface of the magnetic recording medium comprises the rear surface of the nonmagnetic support having at least 1,000 projections having a height of from 200 nm to 400 nm per 0.1 mm2, but with the provisos that not more than 1,000 projections are present having a height of from 400 nm to 700 nm per 0.1 mm2 and not more than 50 projections are present having a height of 700 nm or more per 0.1 mm2.