| 摘要 |
PURPOSE:To prevent the loss of a recording part by forming the recording part, which is carved to form the ruggedness corresponding to information to be recorded, on the surface of a substrate and coating this surface with a rustproof material. CONSTITUTION:A recording part 3 is carved on the upper face of a substrate 1 for the purpose of recognizing various information, and this recording part 3 consists of ruggedness formed with width corresponding to various information. A protective film 2 is not corroded for a long time to protect the recording part 3, and the overall surface of the substrate 1 is coated with a rustproof material like plastics or nickel as a thin film or is plated with Pb or Sn, and the overall surface of the substrate 1 is coated with the protective film 2. Thus, the loss of the recording part 3 is prevented and information is surely kept recorded. |
