Abstract: A method is described for producing a metal thin film type magnetic recording medium having a ferromagnetic metal or alloy thin film provided on a non-magnetic support, comprising the steps of forming said ferromagnetic metal or alloy thin film on said non-magnetic support, and then buffing the surface of said ferromagnetic metal or alloy thin film with nonwoven fabric.

Abstract: A method for preparing a magnetic recording medium comprising the steps of: dispersing ferromagnetic particles in a binder solution; coating the resulting magnetic coating composition on a nonmagnetic support to provide a magnetic layer; drying the magnetic layer; and providing a calendering treatment with the magnetic layer, wherein the binder solution comprises at least one compound selected from the group consisting of a polyurethane resin having a tan .delta. peak temperature of 30.degree. C. or higher as a result of measuring dynamic viscoelasticity, a cellulose acetate butyrate, a cellulose acetate propionate, and a butyral resin; and when the magnetic layer is dried until the solvent content of the magnetic layer is in the range of from 0.1 to 3 wt %, the calendering treatment is provided with the magnetic layer.

Abstract: In a supercalender consisting of a metal roll and an elastic roll and smoothing a web by nipping the web between the metal roll and the elastic roll, the elastic roll satisfies the condition of:Hs(D).gtoreq.-0.1T+85under the condition of 50 to 500 kg/cm of the linear pressure between the metal roll and the elastic roll, where Hs(D) is Shore hardness D-scale of the elastic roll and T is the working temperature (.degree.C.) of the elastic roller that satisfies the condition of 60.gtoreq.T.gtoreq.120.

Abstract: The present invention relates to a magnetic recording medium having on a non-magnetic support a magnetic layer comprising a ferromagnetic fine powder in a binder, in which a colloidal silica having a diameter of 7 to 50 m.mu. and methyl groups on the surface thereof is added in a proportion of 2 to 20 parts by weight to 100 parts by weight of the ferromagnetic fine powder during dispersion of the coating composition of the ferromagnetic fine powder.

Abstract: This invention relates to a magnetic recording substance comprising a support and a magnetic layer containing a ferromagnetic metal powder of liquid phase reduction type in a binder, the ferromagnetic metal powder being obtained by mixing an aqueous slurry containing the ferromagnetic metal powder with an organic solvent capable of forming a minimum boiling azeotropic mixture with water and subjecting the mixture to distillation to remove the water.