Magnetic recording medium

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The magnetic recording medium according to the present invention comprises a magnetic layer on a surface of a non-magnetic support and a backing layer with a thickness of not more than 2 microns on the other surface of the non-magnetic support wherein the backing layer comprises powder and a binder, the powder comprising 1:9 to 10:0 by weight ratio of TiO.
sub.
2 powder to carbon black powder.
The preferable average particle size of titanium oxide (TiO.
sub.
2) ranges from 0.
01 to 0.
8 microns, more preferably from 0.
06 to 0.
4 microns.
The average particle size of carbon black is preferably in the range of 15 to 200 millimicrons, more preferably in the range of 20 to 150 millimicrons.
When carbon black in this range is used together with TiO.
sub.
2 in the backing layer, the thus obtained magnetic recording medium shows reduced dropout.
Excellent antistatic effects are obtainable with the magnetic recording medium of the present invention because TiO.
sub.
2 powder and carbon black powder are both electrically conductive.
Furthermore running properties of the magnetic recording medium are improved because minute concaves and convexes are formed on the surface of the backing layer due to the TiO.
sub.
2 contained therein.
When TiO.
sub.
2 powder and carbon black powder are contained in the backing layer in the ratio of 4:6 to 10:0, dropouts cannot occur frequently.
(Refer to FIG.
1) Coefficient of friction is preferably low in the ratio of 4:6 to 6:4 of TiO.
sub.
2 to carbon black, while when TiO.
sub.
2 exceeds the amount in the above-mentioned ratio, coefficient of friction is somewhat increased.
Signal-to-noise ratio is remarkably improved in the range where TiO.
sub.
2 is contained in more than the ratio of 2:8 of TiO.
sub.
2 to carbon black.
Thus, the best effects are available in the ratio of 4:6 to 6:4 of TiO.
sub.
2 to carbon black.
The reduced dropout obtained with the magnetic recording medium of the present invention is thought to be derived from improved running properties and running durability