| 摘要 |
Process for making composite foamed articles by impregnating an open-celled organic foam with an aqueous suspension of an insoluble solid impregnant to deposit the solid within the pores and then drying, using a closed mould system in which the foamed article is confined so that it seals with the walls of the mould and allows differential pressures to be built up across the thickness of the foam. These are used to assist impregnation, control degree of penetration of the impregnant, and drawing off excess liquid. Useful for making fire-resistant tiles from partly expanded polystyrene beads and can include surface-finishing and other steps. In one embodiment, a foam block (4) is moulded in a cavity defined by mould parts (1) and (2), the parts moved slightly apart, impregnating material (5) introduced into the space between the parts, and the parts reclosed to force the impregnating material partially or fully into the block. In another embodiment a second mould, not that used for forming the block, is used to effect impregnation. The second mould may or may not further shape the block. <IMAGE> |
