摘要 |
A PG-coated product is produced by: producing a body by using PBN; providing a traceability display made of purified graphite in an arbitrary section of the body surface; and covering the body surface including the traceability display with a PG film. By setting the thickness of the PG film to 100μm or less, preferably 80μm or less, it is possible to provide transparency sufficient for reading the product serial number displayed on the body surface. Thus, this is a suitable way of displaying traceability. Because graphite does not adversely affect the physical properties of PBN and PG, the functions and durability intrinsic to the product are not impaired, even when the traceability display, which is formed by using graphite, is placed between the body surface made of PBN and the PG film. |