| 摘要 |
<p>PURPOSE:To obtain a magnetic recording medium equipped with a bar code with high safety in its security protection by making up of the combination of a bar code with a first bar containing magnetic material particles and a second bar containing solid particles having the same shape and size as the magnetic material particles but having no magnetism. CONSTITUTION:In a magnetic recording medium provided with discriminative information comprising a bar code 3, the bar code 3 is composed of the combination of a first bar A of an arbitrary number containing magnetic material particles (such as needle like maghematite particles) and a second bar B of an arbitrary number containing solid particles (such as hematite particles) having the same shape and size as the magnetic material particles but having no magnetism. As a result, each bar forming the bar code is exceedingly difficult to be distinguished by the appearance, and thus a magnetic recording medium can be obtained which has a bar code with extremely high safety in the security protection of a magnetic recording medium.</p> |
