| 摘要 |
<p>The water proof tray is for keeping foodstuffs. It is made from a sheet of corrugated cardboard covered with a sheet of water proof paper to make a base (2). From this rise four sides, in parallel pairs and symmetrical (3,8) formed by bending. Two of the four sides block the folds of four corner or angle parts (5). The other two sides have an outer edge, less to increase rigidity as to give impermeability over all the outside of the tray.</p> |
