The tape reel includes the cylindrical portion and a bottom portion having an installation surface on which the cylindrical portion is installed upright. The installation surface has a central surface located on a center side of the bottom portion, and a first inclined surface formed on an outer peripheral portion of the central surface along a peripheral direction of the cylindrical portion and inclined such that a wall thickness of the bottom portion gradually decreases toward an outer peripheral side. A through hole penetrating the bottom portion is formed in the outer peripheral portion, a pair of wall portions are installed upright on the first inclined surface on both sides of the through hole in the peripheral direction, and a second inclined surface having an inclination angle smaller than an inclination angle of the first inclined surface with respect to the central surface is formed on a surface of each of the wall portions, which is connected to the central surface.

The tape reel includes the cylindrical portion and a bottom portion having an installation surface on which the cylindrical portion is installed upright. The installation surface has a central surface located on a center side of the bottom portion, and a first inclined surface formed on an outer peripheral portion of the central surface along a peripheral direction of the cylindrical portion and inclined such that a wall thickness of the bottom portion gradually decreases toward an outer peripheral side. A through hole penetrating the bottom portion is formed in the outer peripheral portion, a pair of wall portions are installed upright on the first inclined surface on both sides of the through hole in the peripheral direction, and a second inclined surface having an inclination angle smaller than an inclination angle of the first inclined surface with respect to the central surface is formed on a surface of each of the wall portions, which is connected to the central surface.

The magnetic tape cartridge includes a magnetic tape, and a cartridge reel, in which, in the magnetic tape, a minimum winding deviation occurrence load measured after the magnetic tape is rewound around the cartridge reel by applying a tension of 0.20 N in a longitudinal direction of the magnetic tape is 200 N or less.

The magnetic tape cartridge includes a magnetic tape, and a cartridge reel, in which, in the magnetic tape, a minimum winding deviation occurrence load measured after the magnetic tape is rewound around the cartridge reel by applying a tension of 0.20 N in a longitudinal direction of the magnetic tape is 200 N or less.

A tape media cartridge includes a cartridge housing having a standard form factor, a cartridge reel that is coupled to and retained within the cartridge and a tape media. The tape media can be selectively wound onto the cartridge reel between a fully wound state, a partially wound state and an unwound state. The tape media forms a media hollow cylinder having a media outer diameter and a media inner diameter that varies depending upon the state of the tape media. When the tape media is in the fully wound state, the tape media has a ratio of the media outer diameter to media inner diameter of at least approximately 95:43. The cartridge housing can include a side wall having a wall center and wall edge, the side wall having a side wall thickness that gradually increases from the side wall center to the side wall edge.

A tape media cartridge includes a cartridge housing having a standard form factor, a cartridge reel that is coupled to and retained within the cartridge and a tape media. The tape media can be selectively wound onto the cartridge reel between a fully wound state, a partially wound state and an unwound state. The tape media forms a media hollow cylinder having a media outer diameter and a media inner diameter that varies depending upon the state of the tape media. When the tape media is in the fully wound state, the tape media has a ratio of the media outer diameter to media inner diameter of at least approximately 95:43. The cartridge housing can include a side wall having a wall center and wall edge, the side wall having a side wall thickness that gradually increases from the side wall center to the side wall edge.

A tape is prevented from moving in a width direction and the tape is prevented from being damaged in a state in which the tape is wound around a tape reel. There is provided a tape reel including: a cylindrical portion around which a tape is wound; a first flange annularly projecting toward an outer side in a radial direction of the cylindrical portion from the cylindrical portion; and a second flange separated from the first flange in an axial direction of the cylindrical portion and annularly projecting toward the outer side in the radial direction from the cylindrical portion, in which a distance between the first flange and the second flange becomes narrower while extending toward the outer side in the radial direction, and a bending elastic modulus of the first flange is smaller than a bending elastic modulus of the second flange.

A tape is prevented from moving in a width direction and the tape is prevented from being damaged in a state in which the tape is wound around a tape reel. There is provided a tape reel including: a cylindrical portion around which a tape is wound; a first flange annularly projecting toward an outer side in a radial direction of the cylindrical portion from the cylindrical portion; and a second flange separated from the first flange in an axial direction of the cylindrical portion and annularly projecting toward the outer side in the radial direction from the cylindrical portion, in which a distance between the first flange and the second flange becomes narrower while extending toward the outer side in the radial direction, and a bending elastic modulus of the first flange is smaller than a bending elastic modulus of the second flange.

Provided are a magnetic tape, a magnetic tape cartridge and a magnetic tape apparatus including the magnetic tape. The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder. An amount of a fluid lubricant extracted from a surface of the magnetic layer after sliding on a magnetic head in an environment of a temperature of 60° C.±1° C. and a relative humidity of 10% is 50% or more of an amount of the fluid lubricant extracted from the surface of the magnetic layer before the sliding, on a mass basis.

Provided is a magnetic recording medium capable of implementing higher-density recording. This magnetic recording medium includes a substrate containing a polyester and a magnetic layer disposed on the substrate, including a plurality of types of magnetic powder. A surface of the magnetic layer has an arithmetic average roughness Ra of 2.5 nm or less. PSD to a spatial wavelength of 5 μm is 2.5 μm or less. The magnetic layer has an average thickness of 90 nm or less. The magnetic powder has an average aspect ratio of 1.0 or more and 3.0 or less. A coercive force in a perpendicular direction is 3000 oersted or less. A ratio of a coercive force in a longitudinal direction to the coercive force in the perpendicular direction is 0.8 or less. A half-value width of an isolated waveform in a reproduced waveform of a data signal is 200 nm or less.