Abstract: Magnetic recording media comprise a non-magnetic base and one or more magnetic layers consisting of an organic binder matrix containing finely divided magnetic material, the said matrix being obtained by electron beam curing of a mixture of from 70 to 90% by weight of a polyurethane acrylate polymer possessing polymerizable double bonds and from 10 to 30% by weight of one or more copolymerizable compounds.

Abstract: Magnetic recording media comprise a non-magnetic base and one or more magnetic layers consisting of an organic binder matrix containing finely divided magnetic material, the said matrix being obtained by electron beam curing of a mixture of from 50 to 100% by weight of a polyurethane acrylate polymer possessing polymerizable double bonds and from 0 to 50% by weight of an acrylate and/or an acrylate prepolymer and/or an N-vinyl monomer and/or an N-vinyl prepolymer.

Abstract: Magnetic recording media which have a thin backing coating and consist of a non-magnetic flexible base and a magnetic layer which is applied to one side of the base and comprises magnetic material finely dispersed in an organic binder are produced by applying a dispersion of finely divided non-magnetizable conductive and non-conductive solids and conventional additives in a solution of a polymeric binder in an organic solvent to that side of the base which is opposite the magnetic layer by means of a knife-coater, and then drying the layer, a high molecular weight organic compound which acts as a thickener being added to the backing coating dispersion.

Abstract: Magnetic recording media are produced by a method wherein a fluid dispersion of finely divided magnetically anisotropic material in a film-forming binder mixture containing a polyurethane (obtained from a polyester which possesses free hydroxyl groups, and a di- or polyisocyanate) is applied to a non-magnetic base and the magnetic layer is then hardened.

Abstract: A magnetic recording medium comprising a non-magnetic base which is dimensionally stable at up to 300.degree. C., and an 0.03-0.4 .mu.m thick magnetically hard recording layer of an Sm-Co alloy, vacuum-deposited thereon, which layer possesses uniaxial magnetic anisotropy in the plane of the layer, and a process for the manufacture of this recording medium.

Abstract: A magnetic recording medium comprising a non-magnetic base which is dimensionally stable at up to 300.degree. C., and an 0.03-0.4 .mu.m thick magnetically hard recording layer of an Sm-Co alloy, vacuum-deposited thereon, which layer possesses uniaxial magnetic anisotropy in the plane of the layer, and a process for the manufacture of this recording medium.

Abstract: Chromium dioxide magnetic pigments are stabilized against loss of their magnetic properties by treating them, in aqueous and/or alcoholic suspension, with a block copolymer consisting of siloxane units and alkyleneoxy units of 2 to 4 carbon atoms, the alkyleneoxy units being bonded to the polysiloxane radical by a Si--O--C or Si--C group, in an amount of from 1 to 40% by weight based on the chromium dioxide, after which the latter is separated off and dried at from 50.degree. to 200.degree. C. The stabilized chromium dioxide magnetic pigments may be used for the manufacture of magnetic recording media exhibiting improved stability of the magnetic properties under adverse climatic conditions.

Abstract: A process for the manufacture of acicular gamma-iron(III) oxide which, because of its improved dispersibility in organic binders, is suitable for the manufacture of magnetic recording media exhibiting a particularly high orientation ratio. For this purpose, the non-magnetic acicular .alpha.-iron(III) oxide or goethite pigment is treated with from 0.5 to 10% by weight, based on the pigment, of a compound of the formula I: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are hydrogen, alkyl of 1 to 24 carbon atoms or alkenyl of 1 to 24 carbon atoms and (RX).sup.- is selected from the group consisting of an aliphatic carboxylic acid of 1 to 18 carbon atoms, an aromatic carboxylic acid of 1 to 18 carbon atoms, a sulfonic acid and an ester of phosphoric acid and is then further processed by conventional methods to give gamma-iron(III) oxide.

Abstract: A high-speed roller system for transporting webs of sheeting, preferably for coating the same with a magnetic layer, comprising a suction roller for control of the speed of the web, which suction roller has a surface containing grooves, preferably rhombic grooves, in which the perforations for sucking the sheeting are disposed, preferably at the points of intersection, the ratio of the total cross-sectional area of the perforations to the total surface area of the roller being from 0.7 to 3%.