PANELS FROM SETTLED PARTICLES LIQUID BINDER AND ABSORBENT LAYER

1,216,171. Flat and curved slabs or panels; laminates. CEBEM A.G. 1 Jan., 1969 [19 Jan., 1968], No. 127/69. Headings B5A and B5N. Flat and curved slabs or panels, e.g. wall panels, silos, pipes, walls, roofs, floors &c. are produced by spreading a mixture of solid particles and binder on a base, the quantity of binder being in sufficient excess to form an upper layer after the solid particles have settled, inserting into said upper layer one side of an absorbent layer so as to absorb the excess and then curing the binder. Preferably, further layers of settled solid particles and excess binder are applied to the other side of the absorbent layer, the binder being cured on both sides simultaneously. The binder may be an isophthalic, phthalic, bisphenolic or other polyester with a curing agent, e.g. hexamethylene tetramine. The solid particles may be sand, e.g. of particle size 0À15 mm., cement, granular slag, metal powder, e.g. iron powder. The absorbent layer may be a mixture of sand with polyester, in a quantity insufficient to fill the interstices or concrete or corrugated pasteboard.