| 摘要 |
A cellular thermoplastic material (c) is heated to its point of plasticity and inserted between two parts (a, b) of a tool assembly where it is shaped by squeezing together said parts (a, b), whereafter it is allowed to cool down before the tool assembly is opened. The resulting body has a curved surface projecting out over the eyes and joined to a curved surface fitting the wearer's forehead. |
