Abstract: Disclosed is a magnetic recording medium which comprises a non-magnetic support and a layer containing .alpha.-iron oxide powder as a lower layer and a layer containing ferromagnetic powder as an upper layer which are provided on the non-magnetic support in this order from a side of the non-magnetic support, wherein weight ratios of elements in the whole composition of the .alpha.-iron oxide powder are 0.05 to 5 parts by weight of aluminum (Al) atom and 0.05 to 5 parts by weight of silicon (Si) atom based on 100 parts by weight of iron (Fe) atom, and average existence ratios of elements in terms of the number of atoms forming the surface of the .alpha.-iron oxide powder are 40 or less of Al atom and 1 to 60 of Si atom based on the number of Fe atom as 100.

Abstract: A magnetic recording medium is disclosed. The magnetic recording medium is produced by coating the following magnetic paints on a support in the order from the support,a lower layer magnetic paint having a creep strain of 20% to 1000% determined in the conditions with non-volatile content of the paint of 30 weight percent, a temperature 20.degree. C., and a loading weight of 1 Pascal, andan upper layer magnetic paint having a creep strain of 10% to 500% determined in the same conditions.

Abstract: A magnetic recording medium comprises a non-magnetic support and provided thereon, in order, a non-magnetic layer containing a non-magnetic powder, and a magnetic layer containing a ferromagnetic metal powder, each layer containing a binder, the crystallite size of the magnetic powder determined according to X-ray measurement being 30 to 120 .ANG. and the dry thickness of the magnetic layer being 0.01 to less than 0.5 .mu.m.

Abstract: A magnetic recording medium comprising at least two magnetic layers provided on a non-magnetic support, and a backing layer on the support on the side opposite to said magnetic layers, wherein said backing layer has, on the surface thereof, the protrusions each having a height of the peaks thereof within the range of 0.05 .mu.m to 0.6 .mu.m wherein the amount of the protrusions is within the range of 10,000 to 100,000 cm.sub.2 and an interval of the peaks of not less than 10 .mu.m.

Abstract: The improved magnetic recording medium having a magnetic layer on one side of a base support and a backcoat containing a binder and a carbon black on the other side is characterized in that the backcoat further contains an inorganic powder having a hardness of 3-6 on the Mohs scale, the carbon black having an average particle size of 20-100 m.mu., and the binder containing nitrocellulose having a viscosity of 1/8-1/3 second as measured by the falling-ball method.

Abstract: A medium recording medium is provided which has a plurality of coated layers on a nonmagnetic base support, a least one of said coated layer containing a modified copolymer having introduced therein an anionic functional group which forms an intramolecular salt.

Abstract: The method of improving a magnetic recording medium having a support, provided thereon a magnetic layer, and provided on an another side of the support a back coating layer, is disclosed. The improvement comprises the back coating layer containing a binder and a non-magnetic powder comprising essentially of a combination of carbon black and a non-magnetic particle selected from the group consisting of zinc oxide, titanium oxide, barium sulfate, ferric oxide and calcium carbonate.