Abstract: Provided are a magnetic tape including a non-magnetic support and a magnetic layer including a ferromagnetic powder, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape. An amount of a fluid lubricant collected by wiping a surface of the magnetic layer by a nonwoven fabric is in a range of 5 to 400 ng/m2 as a value per unit area of the surface of the magnetic layer.

Abstract: Optical information recording medium comprises: a plurality of recording layers 14, each of which undergoes a change in refractive index by irradiation with recording beam; and an intermediate layer 15 provided between recording layers 14. The recording layer 14 contains polymer binder and dye dispersed in the polymer binder, and at least in proximity to an interface (far-side interface 18) between the intermediate layer 15 and a recording layer 14 disposed adjacent to incident side of the intermediate layer 15 from which the recording beam enters the intermediate layer, the intermediate layer 15 has refractive index different from that of the recording layer 14. Glass transition temperature of the polymer binder is lower than melting point and decomposition point of the dye, and refractive index of the polymer binder changes by receiving heat generated when the dye absorbs the recording beam, whereby information is recordable in the recording layer.