Abstract: A magnetic recording medium includes a substrate, a magnetic layer and a subbing layer therebetween. The subbing layer includes tin oxide type powders having a mean particle size not higher than 0.8 micron. S/N ratio is improved.

Abstract: A magnetic recording medium is disclosed. The medium is comprised of a support base having position thereon a subbing layer and a magnetic layer. The subbing layer is comprised of an amorphous saturated polyester having a glass transition temperature of 10.degree. C. to 60.degree. C. The recording medium provided has excellent adhesiveness between the magnetic layer and the support due to the presence of the subbing layer. Furthermore, the resulting magnetic recording medium provides excellent electromagnetic characteristics such as a desirable video S/N ratio.

Abstract: A method for producing a magnetic recording medium is disclosed. The method involves providing a ferromagnetic coating layer on a non-magnetic support base to produce a coated base. The coated base is then subjected to an atmosphere having a RH of 60% or more, prior to or during a subsequent calendering treatment. The recording medium produced has excellent surface smoothness and improved electromagnetic properties. The method is advantageous in that a substantially long period of time may pass between the coating of the ferromagnetic layer on the support and the calendering treatment without having undesirable effects on the magnetic recording medium produced.

Abstract: A magnetic recording medium is disclosed. The medium is comprised of a non-magnetic flexible support having a subbing layer coated thereon with a magnetic layer coated on the subbing layer. The subbing layer is comprised of a copolymer of a diolefin and a vinyl monomer. The subbing layer provides excellent adhesiveness between the support and the magnetic layer and can be produced without the use of organic solvents. Accordingly, the subbing layer can be economically produced without environmental pollution.

Abstract: A magnetic recording medium is described comprising a magnetic layer on one surface of a non-magnetic base and a back coating on the other surface of the base, said back coating being not more than 2.mu. thick and which contains an inorganic powder and a binder, said inorganic powder consisting of fine particles of an average size of from 0.01 to 0.1.mu. and coarse particles of an average size of from 0.1 to 0.8.mu..

Abstract: This invention relates to an improved magnetic recording medium having an increased durability as well as a decreased head abrasion, which comprises a magnetic recording layer on the surface of a non-magnetic support, the magnetic recording layer containing a ferromagnetic powder, an abrasive having a Mohs' hardness of at least 6, a non-magnetic powder which is granular .alpha.-Fe.sub.2 O.sub.3 and a fatty acid and fatty acid ester.

Abstract: A magnetic recording medium is disclosed which comprises a nonmagnetic support and a magnetic layer formed thereon, said magnetic layer having a center-line average surface roughness of not more than 2.1.times.10.sup.-2 .mu. and at least one property selected from an average pore size of at least 500 .ANG. and a porosity of at least 30%.

Abstract: A magnetic recording medium having a magnetic layer formed on a non-magnetic base is disclosed. The magnetic layer comprises (1) magnetic particles, (2) an abrasive having a Mohs hardness of 6 or more, (3) calcium carbonate, (4) an aliphatic acid and (5) an aliphatic acid ester.

Abstract: A magnetic recording medium is disclosed which is comprised of a non-magnetic support base having a magnetic layer on one surface and a silicone oil layer formed on the opposite surface. The silicone oil layer does not produce dropouts and eliminates scraping and therefore eliminates dust particles that collect and build up in the area of the magnetic head. The silicone layer is formed from a silicone-containing compound having a viscosity of at least 6,000 centistokes at 25.degree. C.

Abstract: A magnetic recording medium having a magnetic layer formed on a nonmagnetic base is disclosed. The magnetic layer comprises ferromagnetic particles having a specific surface area of 30 m.sup.2 /g or more. The particles are dispersed in a binder which comprises a thermoplastic polyurethane resin or polyurethane prepolymer and nitrocellulose having an average degree of polymerization of about 50 to 300 and a degree of nitration of 10.7 to 13.0.

Abstract: A magnetic recording medium having a magnetic recording layer on one side of a non-magnetic base and a lubricant layer on the other side and which is used at a high tape speed of 2 to 10 m/sec. is disclosed. The lubricant layer is characterized by having a thickness of 2.5 to 5 .mu.m and a surface roughness (Ra) of 0.33 to 0.72 .mu.m.

Abstract: In a magnetic recording medium comprising a magnetic recording layer on the surface of a non-magnetic support member, a ferromagnetic powder, an abrasive having a Mohs' hardness of at least 6, colloidal silica and a fatty acid and fatty acid ester are incorporated in the magnetic layer, thus improving the durability of the magnetic layer and decreasing the head abrasion.

Abstract: A magnetic recording medium comprising a magnetic layer on one surface of a non-magnetic base and a back coating on the other surface thereof which is not thicker than 2.mu. and which contains inorganic particles and a binder is disclosed. The inorganic particles have an average size between 0.02 and 5.mu. and a Mohs hardness of 2.5 to 9.0, and the surface of the back coating has a center line average roughness (Ra) of 0.024 or less and the surface of the magnetic layer has a center line average roughness (Ra) of 0.02.

Abstract: The present invention relates to an improved magnetic recording medium comprising a magnetic recording layer on the surface of a non-magnetic support, in which the magnetic recording layer contains a fatty acid, high viscosity silicone oil and fatty acid ester.

Abstract: A magnetic recording medium having a magnetic layer on one surface of a nonmagnetic base and a back coating on the opposite surface is disclosed. An undercoat is formed between the nonmagnetic base and the back coating and the back coating is not thicker than 2.mu..

Abstract: Cleaning tape having a cleaning layer formed on one or both sides of a base is disclosed. Said cleaning layer is composed of (1) a binder, (2) an organic polymer powder whose particle size is 3.mu. or more, and (3) an inorganic solid powder whose particle size is 3.mu. or less.

Abstract: A process for producing a magnetic recording medium is disclosed. The process involves coating a non-magnetic base with magnetic coating solution containing fine ferromagnetic particles and a binder comprising nitrocellulose, polyol and an isocyanate having at least two isocyanato groups. In the process, the web having 0.3 to 3 wt % of the residual solvent in the magnetic layer is calendered, and the calendered web is then dried thoroughly.

Abstract: A magnetic recording medium is disclosed which is comprised of a nonmagnetic support base having a magnetic layer disposed on one surface. A back coating is disposed on the opposite surface of the support base in order to provide the magnetic recording medium with greater durability without increasing the coefficient of friction. The back coating is comprised of a binder having inorganic particles dispersed therein, the inorganic particles including SnO.sub.2 particles having an average size of about 0.01 to about 0.8.mu.. The back coating does not reduce the S/N ratio of the recording medium.

Abstract: A magnetic recording medium having a magnetic layer and a backing layer on opposite sides of a support is disclosed. The backing layer comprises an inorganic filler dispersed in a binder wherein the binder comprises one or more cellulosic resins, one or more thermoplastic polyurethane elastomers and one or more polyisocyanates.

Abstract: A method for producing a magnetic recording medium which comprises preparing a dispersion containing a ferromagnetic powder and a binder in the presence of non-alkali beads and coating the resulting dispersion on a non-magnetic support, and a magnetic recording medium obtained by the above method.