Magnetic recording medium

32:

• A magnetic recording medium comprising:
• an average thickness tT satisfies tT≤5.5 μm, and
• a dimensional change amount Δw in a width direction of the magnetic recording medium with respect to a tension change in a longitudinal direction of the magnetic recording medium satisfies 700 ppm/N≤Δw.

33:

• The magnetic recording medium according to claim 32, wherein the dimensional change amount Δw satisfies 750 ppm/N≤Δw.

34:

• The magnetic recording medium according to claim 32, wherein the dimensional change amount Δw satisfies 800 ppm/N≤Δw.

35:

• The magnetic recording medium according to claim 32, wherein the dimensional change amount Δw satisfies Δw≤20000 ppm/N.

36:

• The magnetic recording medium according to claim 32, wherein a temperature expansion coefficient α satisfies 6 ppm/° C.≤α≤8 ppm/° C.

37:

• The magnetic recording medium according to claim 32, wherein a humidity expansion coefficient β satisfies β≤5 ppm/% RH.

38:

• The magnetic recording medium according to claim 32, wherein a Poisson's ratio ρ satisfies 0.3≤ρ.

39:

• The magnetic recording medium according to claim 32, wherein an elastic limit value σMD in a longitudinal direction satisfies 0.8 N≤σMD.

40:

• The magnetic recording medium according to claim 39, wherein the elastic limit value σMD does not depend on a rate V in elastic limit measurement.

42:

• The magnetic recording medium according to claim 41, wherein the recording layer is vertically oriented.

43:

• The magnetic recording medium according to claim 41, wherein the recording layer is a vacuum thin film.

44:

• The magnetic recording medium according to claim 43, wherein the recording layer has an average thickness tm satisfying 9 nm≤tm≤90 nm.

45:

• The magnetic recording medium according to claim 41, wherein the recording layer contains magnetic powder.

46:

• The magnetic recording medium according to claim 45, wherein the recording layer has an average thickness tm satisfying 35 nm≤tm≤90 nm.

47:

• The magnetic recording medium according to claim 43, wherein the magnetic powder contains ε iron oxide magnetic powder, hexagonal ferrite magnetic powder, or Co-containing spinel ferrite magnetic powder.

48:

• The magnetic recording medium according to claim 41, wherein the recording layer includes five or more servo bands.

49:

• The magnetic recording medium according to claim 48, wherein a ratio of a total area of the servo bands with respect to an area of a surface of the recording layer is 4.0% or less.

50:

• The magnetic recording medium according to claim 49, wherein each of the servo bands has a width of 95 μm or less.

51:

• The magnetic recording medium according to claim 41, wherein the recording layer can form 6000 or more data tracks.

52:

• The magnetic recording medium according to claim 41, wherein
• the recording layer can form a plurality of data tracks, and
• each of the data tracks has a width of 3.0 μm or less.

53:

• The magnetic recording medium according to claim 41, wherein the recording layer can record data such that a minimum value of a distance L between magnetization reversals is 50 nm or less.

54:

• The magnetic recording medium according to claim 41, wherein the substrate has an average thickness of 4.2 μm or less.

55:

• The magnetic recording medium according to claim 41, wherein the substrate contains a polyester.

56:

• The magnetic recording medium according to claim 41, comprising
• a back layer, wherein
• the back layer has an average thickness tb satisfying tb≤0.6 μm.

57:

• The magnetic recording medium according to claim 32, comprising
• a back layer, wherein
• the back layer has a surface roughness Rb satisfying Rb≤6.0 nm.

58:

• The magnetic recording medium according to claim 32, comprising
• a magnetic surface and a back surface on an opposite side to the magnetic surface, wherein
• an interlayer friction coefficient μ between the magnetic surface and the back surface satisfies 0.20≤μ≤0.80.

59:

• The magnetic recording medium according to claim 32, wherein a squareness ratio in a perpendicular direction is 65% or more.

60:

• The magnetic recording medium according to claim 32, wherein a squareness ratio in a perpendicular direction is 70% or more.

61:

• The magnetic recording medium according to claim 32, conforming to LTO 9 or later standards.

62:

• The magnetic recording medium according to claim 32, wherein a coercive force Hc1 in a perpendicular direction is 220 kA/m or more and 310 kA/m or less.

63:

• The magnetic recording medium according to claim 32, wherein a coercive force Hc1 in a perpendicular direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1≤0.8.

64-65. (canceled)