| 摘要 |
PURPOSE:To obtain an information recording medium which is improved in flaw resistance by forming recording layers on the pregrooves on a disc-shaped substrate and joining a disk-shaped protective plate via adhesive layers formed to the outside and inside peripheral edges thereto. CONSTITUTION:A pregroove forming layer 3 formed with the pregrooves 2 and the recording layer 4 formed thereon are provided on the disk-shaped substrate 1 consisting of glass, acrylic resin, etc. The disk-shaped protective plate 6 is joined thereto via the adhesive layers 5a, 5b formed on the joint surfaces in the outside peripheral edge and inside peripheral edge on the surface of the substrate 1. The mechanical strength is higher if the protective plate 6 and the peaks of the side wall parts of the pregrooves 2 are in contact with each other. The information recording medium having the improved flaw resistance is thus obtd. |
