Foundry moulds and cores

摘要

Foundry moulds and cores are prepared using a foundry sand/binder which is stood to harden. The binder contains esp., orthophosphoric acid, FeO or a pref. product contg. >=30% FeO. The mixture may also contain Ca, Cd, Zn or Cu oxide or hydroxide, a foaming agent esp., alkylaryl Na sulphonate, and an aliphatic-polyalcohol esp., ethylene glycol, diethylene glycol, propylene glycol or glycerin.