| 摘要 |
<p>Composite for use as a frame section 100A, 100B in a fenestration unit 200, comprising inner 102 and outer 104 members and an intermediate thermal break 106 arranged between them. The thermal break being polyurethane foam, with a density between 160kg/m3 and 250kg/m3, integrally connected to the inner and outer members. The inner and outer members may be made of aluminium, bronze, fibreglass, PVCu, steel or wood. Also claimed is a method of producing the composite by placing inner and outer members spaced apart in a mould (300, Figs. 3-7) and casting and curing an expandable polyurethane foam (105, Fig. 6) within the mould. The mould may comprise fist and second parts (302 and 304, Figs. 3-7) to clamp the inner and outer members against movement and opposing sealing elements (310, Figs. 3-7) to prevent foam egress. The method may involve heating the mould before casting and/or during curing.</p> |
