| 摘要 |
PURPOSE:To obtain excellent characteristics without having edge dislodgment by combining a nonmagnetic base and magnetic layer having specific properties. CONSTITUTION:The nonmagnetic base is formed of a film essentially consisting of polyethylene terephthalate having >=6 cutting fitness index Y and imparts the energy up to <=10% yield elongation and <=1.0kg/mm<2> yield point to the magnetic layer, where Y=-6.36-28.4xi+0.254xc-26DELTAn. In the formula, xi is the ratio I(110)/I(100) of the peak intensity I(110) of X-ray diffraction (110) face and the peak intensity I(100) of X-ray diffraction (100) face; xc is a crystallite size; DELTAn is the difference in the refractive index expressed by DELTAn= nMD-nTD (where nMD is a longitudinal refractive index and nTD is a transverse refractive index). The clean cut surface and the high quality are thereby obtd. and the powder dislodgment, edge damage and drop-out are substantially eliminated. |
