Abstract: No-bake foundry binders that produce foundry shapes with improved hot strength are provided. The binder comprises a polyether polyol component, a polyisocyanate component and a catalyst component that promotes the trimerization of polyisocyanates to polyisocyanurates. Supplemental catalysts that promote the reaction of the isocyanate with the polyols may also be used. Foundry mixes are prepared by mixing the binder with a foundry aggregate and making foundry shapes using the no-bake process.

Abstract: A chemical binder comprising: an ester-based polyol; an isocyanate; and a catalyst capable of catalyzing a reaction between the ester-based polyol and the isocyanate. Preferably, the chemical binder is used in a mouldable mixture comprising a particulate aggregate and the chemical. Such a mouldable mixture would be in, for example, a disposable foundry mould or core. A process for producing a free-standing mould and a process for cast a metal are also described.

Abstract: This invention relates to foundry mixes and their uses. The foundry mixes comprise (a) a foundry aggregate, and (b) a foundry binder comprising in admixture; (1) an acetoacetate ester; (2) an .alpha., .beta. ethylenically unsaturated monomer; and (3) a liquid tertiary amine catalyst having a pK value of 12-14. The foundry mixes are used to prepare foundry shapes made from foundry mixes by a no-bake process.

Abstract: This invention relates to heat curable foundry mixes and binder compositions particularly suitable for making foundry shapes by a hot box process. The binders used are aqueous basic solutions of phenolic resole resins. Salts are added to the binders or the sand to improve the tensile strength of foundry shapes made with the foundry mixes. Silicone compounds are added to the aggregate to improve the water resistance of foundry shapes made with the foundry mixes containing the binder and salt. The foundry shapes are used to prepare metal castings.

Abstract: This invention relates to heat curable foundry mixes and binder compositions particularly suitable for making foundry shapes by a hot box process. The binders used are aqueous basic solutions of phenolic resole resins. Salts are added to the binders or the sand to improve the tensile strength of foundry shapes made with the foundry mixes. Silicone compounds are added to the aggregate to improve the water resistance of foundry shapes made with the foundry mixes containing the binder and salt. The foundry shapes are used to prepare metal castings.

Abstract: The subject invention relates to a hot box process for forming foundry shapes. The foundry shapes are formed with a mixture of an aggregate and certain aqueous basic solutions of phenolic resole resins which act as binders. The use of these binders results in foundry shapes which are cured by heating at elevated temperatures without requiring an acid-generating curing catalyst.