Abstract: A leader tape where an non-magnetic under layer that contains a powder and a binder and a magnetic upper layer are sequentially laminated on at least one face of a support, in which F5 values of the support in a machine direction (MD) and in a transverse direction (TD) are from 80 to 120 MPa respectively, the F5 value in MD is larger than that in TD, and a difference between the F5 value in MD and that in TD is 15 MPa or less.

Abstract: In a master carrier for magnetic transfer which comprises a support that has a transfer-recording pattern arrayed in the track direction thereof in accordance with the information to be transferred to a magnetic recording medium, and a magnetic layer formed on the transfer-recording pattern of the support, the in-plane distance L (mm) between the hill and the valley of the warped master carrier, the vertical-direction distance H (?m) between the two, and the thickness d (mm) of the master carrier are so defined that they satisfy a relation of 0.05?H·d3/L?0.6.

Abstract: In a master carrier for magnetic transfer which comprises a support that has a transfer-recording pattern arrayed in the track direction thereof in accordance with the information to be transferred to a magnetic recording medium, and a magnetic layer formed on the transfer-recording pattern of the support, the in-plane distance L (mm) between the hill and the valley of the warped master carrier, the vertical-direction distance H (?m) between the two, and the thickness d (mm) of the master carrier are so defined that they satisfy a relation of 0.05?H·d3/L?0.6.

Abstract: An information-storage media is provided that includes: (a) a substrate disk 312 having first and second opposing surfaces; (b) a first selected layer 304 on the first surface, the first selected selected layer 308 on the second surface, the second selected layer having a second thickness, wherein the first and second selected layers have a different chemical composition than the substrate disk; and (d) an information-storage layer 412 adjacent to one or both of the selected layers. The first and second thicknesses are different to provide an unequal stress distribution across the cross-section of the media.