| 摘要 |
<p>The method involves providing a plate-shaped work piece (1) which has two top layers (3,5) and a core layer (7) arranged between the two top layers. The latter top layer has an overlaying section which protrudes opposite to the former top layer and the core layer. The overlaying section is so turned down that an inner surface (9a) of the overlaying section appears with a front surface (3b) of the former top layer.</p> |
