1,224,699. Continuous production of foamed profiles. A. SCHAERER. 14 Nov., 1969 [20 Nov., 1968], No. 55887/69. Heading B5A. Foamed profiles of cross-linked resins are continuously formed by introducing a carrier foil 5 into an open-topped carrier section 1, filling the foil with foamable resin from a mixing head 8, moving a covering section 12 over the open top of the carrier section 1 so that the expanding mix fills the section and forces the foil 5 against the walls and maintaining the carrier section 1 and covering section 12 in contact while the resin cross-links. The profile is then removed from the mould and the foam and carrier foil may be separated. The carrier section preferably comprises elongated channel members which are removably joined end to end, but a batch process may be performed in channels with closed ends. The carrier foil 5 may be a metal foil or sheet, an impregnated plastic web or a thermoplastic foil and may be a multilayer laminated foil or have an outer layer of polyvinyl fluoride and an inner layer of non- woven glass fibre. The foil is folded to the shape of the carrier at 6, before it enters the channel and is preferably of the form shown in Fig. 3 having a top flap 9 which together with the side walls completely encloses the formed resin and forms with the side wall a flap through which air escapes as the resin foams. Alternatively the top flap may be attached to the covering section 12 and may not contact the foil 5, the intermediate mould walls being coated with release agent in this case. Reinforcements such as perforated metal strips or impregnated paper board strips may be placed into the carrier foil before the resin is introduced. The covering section 12 is maintained in contact with the carrier section 1 until the resin cross-links by passing both sections between belts 13, 14 running on rollers 26, 27. The foam is preferably polyurethane and may contain foamed glass or foamed clay beads as filler.
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