| 摘要 |
The invention relates to a polymeric, rigid, circular etched substrate (4) for a recording or optical reading disc, and the optical discs obtained by associating with the substrate (4), on which is deposited a sensitive reflective recording layer (3), an entrance face (1) which the laser beam crosses. …<??>The substrate (4) is characterised in that, on the one hand, the polymer used to make it belongs to the family of thermotropic polymers and that, on the other hand, it is prepared by subjecting the thermotropic polymer to a moulding operation by injection into a mould equipped with a system for central injection of the polymeric material. …<IMAGE>… |
