Improvements in and relating to a sand mold and core composition

摘要

A composition suitable for use as a sand mould comprises a mixture of 97%-99,85% by weight of sand and from 0,15%-3% by weight of a polymeric material which is a synthetic water-soluble interpolymer comprising 60%-80% by weight of acrylonitrile and from 20%-40% by weight of acrylic acid or an ammonium, amine, or amino alkanol salt of the interpolymer. The salt-forming compound may be methyl, dimethyl, trimethyl, or triethyl amine, mono-, di-, or tri-ethanol amine, or monopropanol amine. The sand may be foundry sand, or silica flour, alone or in combination with wood flour, sawdust, fire clays, bentonites, straw, hay, boric acid, iron oxide, or sulphuric acid.