| 摘要 |
Spacer material (21) suitable for sandwich constructions (21, 22, 23) is manufactured with the help of a low-pressure chamber (9). Inside a first space (8) at atmospheric pressure air bubbles are introduced into a curing agent-compatible plastics material, for example a thixotropic laminating polyester. The material thus provided with air bubbles is placed on an exposed mould (5) or on a base inside or outside the aforementioned low-pressure chamber. After the material provided with air bubbles has been placed inside the chamber the latter is actuated in order to provide a second pressure which is considerably below the first pressure. The plastics material takes rigid shape at said second pressure inside the chamber for a short tack-free time, and the air bubbles which have been caused to expand by the low pressure are trapped in the plastics material during the solidifying process. |
