URETHANE BINDER COMPOSITIONS FOR NO BAKE FOUNDRY APPLICATION UTILIZING AMINE POLYOLS

摘要

Binder for pref. foundry cores and moulds used for casting light metals comprises a mixt. of an aromatic amine-polyol (I) and a liquid isocyanate. (I) is pref. the reaction prod. of an aromatic amine (esp. aniline or its condensn. prod. with HCHO) and an alkylene oxide (esp. ethylene or propylene oxide). Foundry cores and moulds obtd. from the binder compsn. have good mechanical strength and are non friable but break easily into fragments after having been subjected to low casting temps. They can be therefore easily removed from the cast metal by shaking. The binder hardens at room temp.