| 摘要 |
<p>1. A improved process for producing a complex elastic molded structure of the sandwich type, consisting of a core of polyurethane foam (10) surrounded by a skin, of which at least a part is reinforced with a reinforcing textile sheet (5, 6, 18, 22) impregnated with an epoxy resin adhering to said polyurethane foam, which process consists in : - depositing in a mold (1) intended to be closed by a cover (2), adjacent each of the two main inner faces (1, 2) of this mold, a reinforcing assembly comprising a stiffening element (12) and textile sheets (5, 6, 18, 22) impregnated with epoxy resin ; - closing the cover (2) of the mold (1) so as to define together with said assembly a volume corresponding to the volume of the core which is to be formed ; - then, injecting into the volume thus defined a polyol and an isocyanate, which react so as to form the polyurethane foam wich expands and hardens in situ by an exothermic reaction ; - then, allowing the content of the mold (1) to cool ; - and finally, opening the mold to withdraw the resulting elastic complex molded structure, characterized in that the reinforcing textile sheets (5, 6, 18, 22) are pre-impregnated by passing in a bath of solventless epoxy resin, then drying and pre-hardening by maturing at ambient temperature, leading to non-tacky sheets at ambient temperature.</p> |
