| 摘要 |
PURPOSE:To improve the bonding strength between a hub metallic surface and an adhesive layer of ultraviolet curable resin and to prevent the drop-out of a magnetic metallic hub from a disk substrate by adding another adhesive layer between the magnetic metallic hub and the adhesive layer of ultraviolet curable resin. CONSTITUTION:A magnetic metallic hub 2 pierces through an inner circle part 1a of a disk substrate 1 via a cylindrical part 2b and bonded to a recording film layer of the substrate 1 via an adhesive layer at a base part 2a. This adhesive layer contains a 2nd adhesive layer 4 formed previously at the part 2a of the hub 2 and an adhesive layer 3 of ultraviolet curable resin formed between the layer 4 and the substrate 1. The layer 4 is made of the epoxy resin or the urethane resin having the high wetting property to the hub 2 with 30 - 100mum thickness. As a result, the bonding strength between the substrate 1 and the hub 2 is improved by 2 - 5 times as high as a normal level. Thus the hub 2 is never dropped out of the substrate 1. |
