| 摘要 |
PROBLEM TO BE SOLVED: To achieve high forgery prevention effect by providing: a medium that does not allow additional writing by a laser beam in order to prevent tampering; and a method for manufacturing the medium.SOLUTION: A tampering proof medium is composed of: laminated base material composed of at least three layers of surface base material transmitting a laser beam, core base material to be carbonized by the laser beam, and rear-surface base material; and an OVD (optical variable device) transfer body having a layer colored or discolored by light irradiation with intensity equal to or exceeding specific intensity. The tamper proof medium is configured to record image information and character information in the core base material by irradiating the laser beam without affecting the surface base material. The transfer body is provided on a surface of the laminated base material in which the image information and the character information are recorded in the core base material. |
