Abstract: An aspect of the present invention relates to a magnetic recording medium comprising a nonmagnetic layer containing a nonmagnetic powder and a binder and a magnetic layer containing a ferromagnetic powder and a binder in this order on a nonmagnetic support, wherein the binder of the magnetic layer is a mixture of a vinyl chloride copolymer, polyurethane resin, and polyisocyanate, the polyurethane resin having a glass transition temperature ranging from 90 to 130° C. and a storage elastic modulus at 80° C. ranging from 2.5 to 5.0 GPa, the nonmagnetic layer is a radiation-cured layer formed by curing with radiation a radiation-curable composition comprising a nonmagnetic powder and a binder component, the binder component comprising a radiation-curable vinyl chloride copolymer and a radiation-curable polyurethane resin, and the radiation-curable vinyl chloride copolymer and radiation-curable polyurethane resin both have glass transition temperatures ranging from 30 to 100° C.

Abstract: An aspect of the present invention relates to a magnetic recording medium comprising a nonmagnetic layer containing a nonmagnetic powder and a binder and a magnetic layer containing a ferromagnetic powder and a binder in this order on a nonmagnetic support, wherein the binder of the magnetic layer is a mixture of a vinyl chloride copolymer, polyurethane resin, and polyisocyanate, the polyurethane resin having a glass transition temperature ranging from 90 to 130° C. and a storage elastic modulus at 80° C. ranging from 2.5 to 5.0 GPa, the nonmagnetic layer is a radiation-cured layer formed by curing with radiation a radiation-curable composition comprising a nonmagnetic powder and a binder component, the binder component comprising a radiation-curable vinyl chloride copolymer and a radiation-curable polyurethane resin, and the radiation-curable vinyl chloride copolymer and radiation-curable polyurethane resin both have glass transition temperatures ranging from 30 to 100° C.

Abstract: An aspect of the present invention relates to a magnetic recording medium comprising a magnetic layer comprising a ferromagnetic power and a binder on a nonmagnetic support, wherein, the binder comprises a constituent component in the form of a polyurethane resin obtained from starting materials in the form of a polyisocyanate and a polyol denoted by general formula (I): wherein, in general formula (I), Z1 denotes an atom group forming a lactone ring with two adjacent carbon atoms.

Abstract: The present invention relates to a method of manufacturing a magnetic recording medium wherein the magnetic layer coating liquid comprising a ferromagnetic powder having an average particle size of 10 to 40 nm and a moisture content of 0.3 to 3.0 weight percent; a binder (a) comprising 0.2 to 0.7 meq/g of at least one polar group selected from the group consisting of —SO3M, —OSO3M, —PO(OM)2, —OPO(OM)2, and COOM (M denotes a hydrogen atom or the like) and having a weight average molecular weight of 20,000 to 200,000, and/or (b) comprising 0.5 to 5 meq/g of at least one polar group selected from the group consisting of —CONR1R2, —NR1R2, and —NR+R1R2R3 (wherein R1, R2, and R3 each independently denote a hydrogen atom or the like) and having a weight average molecular weight of 20,000 to 200,000; and a compound comprising at least one carboxyl group and/or hydroxyl group per molecule.

Abstract: An aspect of the present invention relates to a method of modifying a surface of a magnetic powder, comprising mixing a magnetic powder with a cyclic compound comprising at least one carboxylic group. A further aspect of the present invention relates to a magnetic coating material comprising a magnetic powder and a binder, further comprising a cyclic compound comprising at least one carboxylic group.

Abstract: An aspect of the present invention relates to a method of modifying a surface of a powder, comprising mixing a powder with a heterocyclic compound comprising at least one hydroxylic group and/or carboxylic group. The present invention further relates to a magnetic recording medium and a coating material.